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Discussion Starter · #1 ·
Let me officially say; whom ever decided and designed to put the fuse block on my 81 where they did, needs a good Will Smith type slap!
:mad:WTF... I'm not 4 foot tall and a contortionist... that thing is virtually impossible to get to... especially the AC fuse!
 

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hamerDown you got that right!! I'm an old fart and every time I go "fuse diving" I wonder if it will be my last move on earth! Takes a while to get all straightened out. On my 81, I completely stripped everything out to the bare body and when putting it all back together the fuse block was still a PITA, even with nothing else around it. Reminds me of a couple things I'll share: When I had the fuse block out, I decided to clean it all up. But when I wiped the face of the block where all the labels were, they all wiped off! Luckily I had taken many pictures so I was able to use a Brother label maker with narrow white on black tape to relabel everything. After some careful trimming they came out pretty good. If you look closely you can see the tape. The other picture here is what's on the firewall side of the fuse block. Let's hope you never have to get into that, it is a challenge to say the least!
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Bet that was an oh $hit moment. I don’t own a C3 but plenty of autos of that era had fuse blocks that were in some hard to get to places. I was young back then and trouble getting to them. Man I hate to think now.
 

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Discussion Starter · #4 · (Edited)
hamerDown you got that right!! I'm an old fart and every time I go "fuse diving" I wonder if it will be my last move on earth! Takes a while to get all straightened out. On my 81, I completely stripped everything out to the bare body and when putting it all back together the fuse block was still a PITA, even with nothing else around it. Reminds me of a couple things I'll share: When I had the fuse block out, I decided to clean it all up. But when I wiped the face of the block where all the labels were, they all wiped off! Luckily I had taken many pictures so I was able to use a Brother label maker with narrow white on black tape to relabel everything. After some careful trimming they came out pretty good. If you look closely you can see the tape. The other picture here is what's on the firewall side of the fuse block. Let's hope you never have to get into that, it is a challenge to say the least! View attachment 105355

View attachment 105356
That looks GREAT and hopefully it's an exact representation on my 81 because I just took a picture of your picture!
I'm now 64, purchased my 81 new... I can't contort myself like an Octopus anymore.
The female side of AC fuse block is very loose, not sure what I can do to tighten it up.
Question; So does the back 1/2 of the block separate from what we see on the inside???
Yesterday while I was twisting my body like a slinky and cursing like a drunken Sailor trying to get at my AC fuse I noticed a wire pulled out of somewhere. I'll try to take a picture and maybe you can tell me where it pulled out from.
I swear, the only fun thing about these cars is driving them (when nothing needs work) and washing/waxing it... everything else with these cars absolutely SUCKS!
Oh, and I still have the original heater core... I'll probably burn it before doing that job.
 

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That looks GREAT and hopefully it's an exact representation on my 81 because I just took a picture of your picture!
I'm now 64, purchased my 81 new... I can't contort myself like an Octopus anymore.
The female side of AC fuse block is very loose, not sure what I can do to tighten it up.
Question; So does the back 1/2 of the block separate from what we see on the inside???
Yesterday while I was twisting my body like a slinky and cursing like a drunken Sailor trying to get at my AC fuse I noticed a wire pulled out of somewhere. I'll try to take a picture and maybe you can tell me where it pulled out from.
I swear, the only fun thing about these cars is driving them (when nothing needs work) and washing/waxing it... everything else with these cars absolutely SUCKS!
Oh, and I still have the original heater core... I'll probably burn it before doing that job.
hamerDown Impressive that you bought your 81 new! I bought a brand new 82 but had to sell it after about a year due to kids, etc. I bought my 81 about 5 years ago, sort of picked up where I left off! I'll be 71 in a couple months so I can relate to getting under the dash! Actually, I usually just pull the seats out if I have to do very much. It's very easy, only 4 bolts from the inside on each seat. Makes a world of difference for access.

I would be happy to try and identify the "mystery" wire if you would post a picture and maybe a description. During this era of the C3, GM apparently ran out of room and open connectors in the fuse block so they have several things that tap into the front of the fuse block. I have them all identified so we could probably figure out which one is loose pretty easily.

I'm not sure exactly what you mean by the female side loose, but the fuse block is secured by 2 long bolts from the cabin side into the bulkhead connector on the engine side of the firewall. If your fuse block is loose, you might check those 2 bolts.

Here is a pic that shows where those 2 bolts go into the fuse block. The upper right hole is barely visible in the photo, but it is just above the ECM 10A fuse.
Light Circuit component Hardware programmer Audio equipment Electrical wiring


For orientation, here is where the 2 bolts go through the firewall. This picture is taken from the inside of the cabin, obviously when I had everything removed.

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This is the bulkhead connector that attaches to the fuse block on the engine side of the firewall, under the brake booster. This view is looking into the bulkhead connector. Obviously it is not in the car at this time.

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There are 2 connectors that plug into the bulkhead connector on the engine side of the firewall under the brake booster. They are C100 and C115. The 2 connectors are joined but can be easily separated once the bolt in the center is removed and the connectors are unplugged. They are joined so that a single bolt can hold them in place. In this view, the orientation is looking into the bulkhead connector from the engine side of the firewall with C100 and C115 unplugged. In this view, C100 would be on your left, closest to the engine. C115 would be on your right, closest to the fender.

Here are the connectors, the orientation here is looking into the connector from the bulkhead connector side. The labeling of the pins can be confusing. If you look closely at C100 and C115 connectors, you can just make out some tiny letters molded into the plastic. Letters A -F identify the horizontal rows while letters S-Z identify the vertical rows.

Office equipment Font Engineering Machine Automotive tire


Rectangle Font Gas Metal Circuit component


Here is a grid I made that helps identify the rows and columns of the bulkhead connector

Rectangle Font Parallel Magenta Pattern

Here is another drawing I made that shows the wiring coming out of C100 and C115. The number before each wire is the circuit number from the schematics in the Service Manual. This is the stock configuration. The wiring in my 81 has been highly modified, I used this to identify circuits that I no longer used and how the new circuits were assigned to terminals no longer used in the bulkhead connector.
Font Parallel Diagram Art Handwriting


I know this is a lot more information than you asked for but I figured while I was at it I'd go ahead and post it. If you ever have reason to remove C100 and C115, it can be done while the vehicle is assembled. But it is a difficult 2-person job. Plus, if the connectors have never been off you will find they are thoroughly gooped up with the GM "miracle sealant", also known as tar! The pictures I have are after I cleaned them up with solvent and lots of elbow grease.

Hope you and others find this useful, meanwhile, try removing the seat(s) next time you go "dashboard diving". You will be amazed how much easier it is, especially for us old timers!
 

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As always zimme, great info and pics
 

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Discussion Starter · #8 · (Edited)
hamerDown Impressive that you bought your 81 new! I bought a brand new 82 but had to sell it after about a year due to kids, etc. I bought my 81 about 5 years ago, sort of picked up where I left off! I'll be 71 in a couple months so I can relate to getting under the dash! Actually, I usually just pull the seats out if I have to do very much. It's very easy, only 4 bolts from the inside on each seat. Makes a world of difference for access.

I would be happy to try and identify the "mystery" wire if you would post a picture and maybe a description. During this era of the C3, GM apparently ran out of room and open connectors in the fuse block so they have several things that tap into the front of the fuse block. I have them all identified so we could probably figure out which one is loose pretty easily.

I'm not sure exactly what you mean by the female side loose, but the fuse block is secured by 2 long bolts from the cabin side into the bulkhead connector on the engine side of the firewall. If your fuse block is loose, you might check those 2 bolts.

Here is a pic that shows where those 2 bolts go into the fuse block. The upper right hole is barely visible in the photo, but it is just above the ECM 10A fuse.
View attachment 105358

For orientation, here is where the 2 bolts go through the firewall. This picture is taken from the inside of the cabin, obviously when I had everything removed.

View attachment 105359

This is the bulkhead connector that attaches to the fuse block on the engine side of the firewall, under the brake booster. This view is looking into the bulkhead connector. Obviously it is not in the car at this time.

View attachment 105360

There are 2 connectors that plug into the bulkhead connector on the engine side of the firewall under the brake booster. They are C100 and C115. The 2 connectors are joined but can be easily separated once the bolt in the center is removed and the connectors are unplugged. They are joined so that a single bolt can hold them in place. In this view, the orientation is looking into the bulkhead connector from the engine side of the firewall with C100 and C115 unplugged. In this view, C100 would be on your left, closest to the engine. C115 would be on your right, closest to the fender.

Here are the connectors, the orientation here is looking into the connector from the bulkhead connector side. The labeling of the pins can be confusing. If you look closely at C100 and C115 connectors, you can just make out some tiny letters molded into the plastic. Letters A -F identify the horizontal rows while letters S-Z identify the vertical rows.

View attachment 105361

View attachment 105362

Here is a grid I made that helps identify the rows and columns of the bulkhead connector

View attachment 105363
Here is another drawing I made that shows the wiring coming out of C100 and C115. The number before each wire is the circuit number from the schematics in the Service Manual. This is the stock configuration. The wiring in my 81 has been highly modified, I used this to identify circuits that I no longer used and how the new circuits were assigned to terminals no longer used in the bulkhead connector.
View attachment 105364

I know this is a lot more information than you asked for but I figured while I was at it I'd go ahead and post it. If you ever have reason to remove C100 and C115, it can be done while the vehicle is assembled. But it is a difficult 2-person job. Plus, if the connectors have never been off you will find they are thoroughly gooped up with the GM "miracle sealant", also known as tar! The pictures I have are after I cleaned them up with solvent and lots of elbow grease.

Hope you and others find this useful, meanwhile, try removing the seat(s) next time you go "dashboard diving". You will be amazed how much easier it is, especially for us old timers!
hamerDown Impressive that you bought your 81 new! I bought a brand new 82 but had to sell it after about a year due to kids, etc. I bought my 81 about 5 years ago, sort of picked up where I left off! I'll be 71 in a couple months so I can relate to getting under the dash! Actually, I usually just pull the seats out if I have to do very much. It's very easy, only 4 bolts from the inside on each seat. Makes a world of difference for access.

I would be happy to try and identify the "mystery" wire if you would post a picture and maybe a description. During this era of the C3, GM apparently ran out of room and open connectors in the fuse block so they have several things that tap into the front of the fuse block. I have them all identified so we could probably figure out which one is loose pretty easily.

I'm not sure exactly what you mean by the female side loose, but the fuse block is secured by 2 long bolts from the cabin side into the bulkhead connector on the engine side of the firewall. If your fuse block is loose, you might check those 2 bolts.

Here is a pic that shows where those 2 bolts go into the fuse block. The upper right hole is barely visible in the photo, but it is just above the ECM 10A fuse.
View attachment 105358

For orientation, here is where the 2 bolts go through the firewall. This picture is taken from the inside of the cabin, obviously when I had everything removed.

View attachment 105359

This is the bulkhead connector that attaches to the fuse block on the engine side of the firewall, under the brake booster. This view is looking into the bulkhead connector. Obviously it is not in the car at this time.

View attachment 105360

There are 2 connectors that plug into the bulkhead connector on the engine side of the firewall under the brake booster. They are C100 and C115. The 2 connectors are joined but can be easily separated once the bolt in the center is removed and the connectors are unplugged. They are joined so that a single bolt can hold them in place. In this view, the orientation is looking into the bulkhead connector from the engine side of the firewall with C100 and C115 unplugged. In this view, C100 would be on your left, closest to the engine. C115 would be on your right, closest to the fender.

Here are the connectors, the orientation here is looking into the connector from the bulkhead connector side. The labeling of the pins can be confusing. If you look closely at C100 and C115 connectors, you can just make out some tiny letters molded into the plastic. Letters A -F identify the horizontal rows while letters S-Z identify the vertical rows.

View attachment 105361

View attachment 105362

Here is a grid I made that helps identify the rows and columns of the bulkhead connector

View attachment 105363
Here is another drawing I made that shows the wiring coming out of C100 and C115. The number before each wire is the circuit number from the schematics in the Service Manual. This is the stock configuration. The wiring in my 81 has been highly modified, I used this to identify circuits that I no longer used and how the new circuits were assigned to terminals no longer used in the bulkhead connector.
View attachment 105364

I know this is a lot more information than you asked for but I figured while I was at it I'd go ahead and post it. If you ever have reason to remove C100 and C115, it can be done while the vehicle is assembled. But it is a difficult 2-person job. Plus, if the connectors have never been off you will find they are thoroughly gooped up with the GM "miracle sealant", also known as tar! The pictures I have are after I cleaned them up with solvent and lots of elbow grease.

Hope you and others find this useful, meanwhile, try removing the seat(s) next time you go "dashboard diving". You will be amazed how much easier it is, especially for us old timers!
WOW... you really got into it but if I may ask... 'why'... where there some electrical gremlins going on etc when you purchased your 81?
Did you do a frame-off restore on the 81?
Yes, I should have pulled the drivers seat as it does help. I just thought the maybe the AC fuse was making a poor contact as it has in the past and the AC would again work... this time no such luck, the AC-charge from last June leaked out 'somewhere' and that will be my next thread.
If you see in the picture there is a GREY wire that pulled out from somewhere.
One thing I did notice; when exiting the car and closing the drivers door the overhead dome light use to stay on for maybe 15 seconds then go out. Now, when exiting the car and shutting the drivers door the overhead dome light just turns off. Not sure 'if' that grey wire has anything to do with that.
As to the AC fuse; what I meant was... the female prongs that hold the 25a AC fuse 'in' no longer holds it snugly, kinda loose. EDIT... I know see that brown wire up to the right, looks like something cut it. At the fuse block the brown wire is exiting at LPS???
EDIT
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hamerDown: I don't really see a loose grey wire, but there is a wire that looks to be cut that is either grey or brown! I'll focus on this one and call it grey. The grey wire originates from the LPS power tap on the fuse block and runs directly to the key/seatbelt buzzer. That's the black "box" plugged into a connector on the right side of the fuse block. I found a picture of mine before I took it all apart so you can see how it is connected. On yours, it appears that the wire has been cut or broken in two, probably to silence the awful buzzer the C3's of this era had. Here's the picture of mine:
Passive circuit component Circuit component Light Hardware programmer Audio equipment


And here's the picture of yours. I put a red arrow on the 2 ends of the wire.
Circuit component Audio equipment Electrical wiring Electronic component Hardware programmer


That is one of those power "taps" that I spoke of. The 81 uses several of them which can add to the confusion when troubleshooting. I didn't thoroughly trace it out but I doubt if the grey wire has anything to do with the interior light delay. The delay is controlled by a yellow box, about half the size of a cigarette pack, that is located on the far right (passenger side) of the glove box. It is really buried in there, usually it's easier to remove the glove box insert to get to it. Here is a page from the 81 Service Manual that shows the delay module circuits.
Schematic Rectangle Font Parallel Engineering


Speaking of the 81 GM Service Manual for the Corvette, there are many errors in the schematics. For example, the schematic for the seat belt/key buzzer on page 8A-36 of the manual is not correct for the 81. That's why I didn't post it here. Frequently you can find the correct schematic in the 82 Service Manual. Go figure....

I spent a lot of time putting together a "decoder ring" for the fuse block power distribution in the 81. I'll attach it here, it is a pdf file. It looks a little busy but studying it for a short time will provide lots of useful information. Since I was making a lot of modifications I needed this to determine power sources and remove unneeded circuits. There is a color code for the connections on each page:

A bridge, or connection, behind the fuse block is indicated by a blue line with a white stripe.

A fuse block power tap is indicated by a purple line with a white stripe.

The other wires are the color code used for the actual connection.

I also labeled each connection as to the power source (hot all the time, switched, etc) and where the power goes out of the fuse block.

The next to the last page shows the LPS power tap with the grey wire. Guess I should have numbered the pages!

Regarding your AC fuse being loose, this is common on these C3's. It is possible to replace the fuse "socket", but I don't recommend doing so unless you are doing a complete teardown of the wiring harnesses. You pretty much have to have the fuse block completely out and on the bench to do it correctly. I recommend "intercepting" the wire(s) on the downwind side of the fuse. Then remove the AC fuse from the panel and tap into the wire to the AC. Do the same thing on the upwind side of the fuse where the power comes in. Then add a quality in line fuse holder with a pigtail on each end and connect the power source to the load. This bypasses the faulty fuse socket with an in line fuse. It isn't elegant, but if you are careful you can make the in line fuse holder hidden from view. If you aren't comfortable getting this deep into it I'm sure you can find someone that is competent to do this.

Yes, I did a resto-mod on my 81. I swapped in an LS-3 and t-56 transmission along with many other changes. I didn't use very much of the interior wiring, replaced it with new harnesses I built. The external light wiring is about the only wiring I didn't modify. My build is on this forum, if you want to take a look here is the link:


The pdf attachment should be here somewhere.

Good luck, let us know how it's going and feel free to ask questions!
 

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Discussion Starter · #10 ·
hamerDown: I don't really see a loose grey wire, but there is a wire that looks to be cut that is either grey or brown! I'll focus on this one and call it grey. The grey wire originates from the LPS power tap on the fuse block and runs directly to the key/seatbelt buzzer. That's the black "box" plugged into a connector on the right side of the fuse block. I found a picture of mine before I took it all apart so you can see how it is connected. On yours, it appears that the wire has been cut or broken in two, probably to silence the awful buzzer the C3's of this era had. Here's the picture of mine:
View attachment 105368

And here's the picture of yours. I put a red arrow on the 2 ends of the wire.
View attachment 105369

That is one of those power "taps" that I spoke of. The 81 uses several of them which can add to the confusion when troubleshooting. I didn't thoroughly trace it out but I doubt if the grey wire has anything to do with the interior light delay. The delay is controlled by a yellow box, about half the size of a cigarette pack, that is located on the far right (passenger side) of the glove box. It is really buried in there, usually it's easier to remove the glove box insert to get to it. Here is a page from the 81 Service Manual that shows the delay module circuits.
View attachment 105370

Speaking of the 81 GM Service Manual for the Corvette, there are many errors in the schematics. For example, the schematic for the seat belt/key buzzer on page 8A-36 of the manual is not correct for the 81. That's why I didn't post it here. Frequently you can find the correct schematic in the 82 Service Manual. Go figure....

I spent a lot of time putting together a "decoder ring" for the fuse block power distribution in the 81. I'll attach it here, it is a pdf file. It looks a little busy but studying it for a short time will provide lots of useful information. Since I was making a lot of modifications I needed this to determine power sources and remove unneeded circuits. There is a color code for the connections on each page:

A bridge, or connection, behind the fuse block is indicated by a blue line with a white stripe.

A fuse block power tap is indicated by a purple line with a white stripe.

The other wires are the color code used for the actual connection.

I also labeled each connection as to the power source (hot all the time, switched, etc) and where the power goes out of the fuse block.

The next to the last page shows the LPS power tap with the grey wire. Guess I should have numbered the pages!

Regarding your AC fuse being loose, this is common on these C3's. It is possible to replace the fuse "socket", but I don't recommend doing so unless you are doing a complete teardown of the wiring harnesses. You pretty much have to have the fuse block completely out and on the bench to do it correctly. I recommend "intercepting" the wire(s) on the downwind side of the fuse. Then remove the AC fuse from the panel and tap into the wire to the AC. Do the same thing on the upwind side of the fuse where the power comes in. Then add a quality in line fuse holder with a pigtail on each end and connect the power source to the load. This bypasses the faulty fuse socket with an in line fuse. It isn't elegant, but if you are careful you can make the in line fuse holder hidden from view. If you aren't comfortable getting this deep into it I'm sure you can find someone that is competent to do this.

Yes, I did a resto-mod on my 81. I swapped in an LS-3 and t-56 transmission along with many other changes. I didn't use very much of the interior wiring, replaced it with new harnesses I built. The external light wiring is about the only wiring I didn't modify. My build is on this forum, if you want to take a look here is the link:


The pdf attachment should be here somewhere.

Good luck, let us know how it's going and feel free to ask questions!
Great info and thank you for taking the time doing so. Once I saw my posted picture and being it is much bigger I did see the gray seat belt buzzer wire appears to be cut. Funny thing, I absolutely do not recall doing that, but I must have lol.
As to adding a pigtail for a separate AC fuse holder I like that idea however, I find doing anything under that dash and fuse-block area chasing wires to be a cramped, difficult task but I'll give it a look. I wish I had a lift, my body doesn't bend like a pretzel anymore.
Awesome and quite the task you performed on your 81... that's a labor of love right there and you must have a lot of patience and the space/shop to perform such a job comfortably.
 

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Great info and thank you for taking the time doing so. Once I saw my posted picture and being it is much bigger I did see the gray seat belt buzzer wire appears to be cut. Funny thing, I absolutely do not recall doing that, but I must have lol.
As to adding a pigtail for a separate AC fuse holder I like that idea however, I find doing anything under that dash and fuse-block area chasing wires to be a cramped, difficult task but I'll give it a look. I wish I had a lift, my body doesn't bend like a pretzel anymore.
Awesome and quite the task you performed on your 81... that's a labor of love right there and you must have a lot of patience and the space/shop to perform such a job comfortably.
hamerDown thank you for the kind words! Yes, it was a labor of love. I've messed with cars and street racers most all my life but I always wanted to do a car to this level. I wanted a fast yet reliable car that I could actually drive, and I wanted it to look brand new no matter where you looked. That was the genesis for selecting the LS-3. It is stock for reliability yet has sufficient power to keep me on the edge of my seat! For all those years family responsibilities took precedence, but I finally got to the stage of life where I could actually do this. VERY rewarding project!

I'll take a look at the circuits and see if I can locate a relatively easy way to bypass the defective fuse socket. Stay tuned!
 

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Discussion Starter · #12 ·
hamerDown thank you for the kind words! Yes, it was a labor of love. I've messed with cars and street racers most all my life but I always wanted to do a car to this level. I wanted a fast yet reliable car that I could actually drive, and I wanted it to look brand new no matter where you looked. That was the genesis for selecting the LS-3. It is stock for reliability yet has sufficient power to keep me on the edge of my seat! For all those years family responsibilities took precedence, but I finally got to the stage of life where I could actually do this. VERY rewarding project!

I'll take a look at the circuits and see if I can locate a relatively easy way to bypass the defective fuse socket. Stay tuned!
Thank you for your time, much appreciated!
BTW, been thinking about your current Vette... WOW... you touched 'everything' on that vehicle and rebuilt and/or made improvements to the car! And from all your efforts you must be extremely proud but also > > > you have an extremely reliable Corvette!
PS ugh, my AC system leaked out over the winter and from last June when it was vacuumed down and refilled. Ninety degree weather coming latter this week. Fingers crossed the Evac core isn't leaking.
And 'if' the original heater core ever leaks (I know that's a nightmare) I'll take a match to it lol
 

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Know what you mean about the heater core leaking! That's definitely a chore. Difficult, not impossible. Since you pretty much have to remove the heater case assembly it's a good idea to make any other repairs/modifications while you are that far into it. Another potential problem is the quality of aftermarket heater cores these days. Many of them come from China and we all know what that means! The ones I've seen aren't even close to the quality of the OEM units.

Here's a couple of pics you don't often see: This is the HVAC system from under the dashboard with the car stripped away!

I assume your 81 has been converted to R134a and no longer uses R12. If it was converted, the o-rings and rubber hoses should be replaced. I have some experience with auto HVAC systems that I've learned over the years but I am definitely not an authority on the subject. I've heard some say that you can use old R12 hoses with R134a but most say you can't. The R134a hoses are called "barrier" hose. They have an additional barrier made inside the hose that keeps the smaller R134a molecules inside. In any case, it would be a good idea to replace all the seals and hoses when doing the conversion since they are getting quite old. Plus, the refrigerant oil for 134a is not compatible with the oil for R12.

I got a little tied up today and didn't look at the AC fuse issue, but I will in the next few days. I think I still have most of the original wiring harnesses from under the hood, that should make it easier to look for a good place to bypass the bad AC fuse holder.

I would encourage an owner of an older Corvette to try and keep the maintenance up as much as possible. Otherwise, the needed repairs can build up to a point where they get overwhelmed. And believe me, I understand tight budgets!

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Discussion Starter · #14 ·
Know what you mean about the heater core leaking! That's definitely a chore. Difficult, not impossible. Since you pretty much have to remove the heater case assembly it's a good idea to make any other repairs/modifications while you are that far into it. Another potential problem is the quality of aftermarket heater cores these days. Many of them come from China and we all know what that means! The ones I've seen aren't even close to the quality of the OEM units.

Here's a couple of pics you don't often see: This is the HVAC system from under the dashboard with the car stripped away!

I assume your 81 has been converted to R134a and no longer uses R12. If it was converted, the o-rings and rubber hoses should be replaced. I have some experience with auto HVAC systems that I've learned over the years but I am definitely not an authority on the subject. I've heard some say that you can use old R12 hoses with R134a but most say you can't. The R134a hoses are called "barrier" hose. They have an additional barrier made inside the hose that keeps the smaller R134a molecules inside. In any case, it would be a good idea to replace all the seals and hoses when doing the conversion since they are getting quite old. Plus, the refrigerant oil for 134a is not compatible with the oil for R12.

I got a little tied up today and didn't look at the AC fuse issue, but I will in the next few days. I think I still have most of the original wiring harnesses from under the hood, that should make it easier to look for a good place to bypass the bad AC fuse holder.

I would encourage an owner of an older Corvette to try and keep the maintenance up as much as possible. Otherwise, the needed repairs can build up to a point where they get overwhelmed. And believe me, I understand tight budgets!

View attachment 105382

View attachment 105383

View attachment 105384

View attachment 105385
Awesome pictures and 'if' by looking at your pictures it appears the heaters core may be accessible from the right side of the dash area and obviously behind the glove box. I'm not sure 'if' by your pictures the center gauge cluster and the large center defroster vent section would also have to come out... but hopefully my original heater core somehow out lives me, and I won't have to dig into that project.
With 'any' of my vehicles, motorcycles and speedboat I'm all about general maintenance and trying to keep-up on things. 2014 I needed a major distraction from a horrible and horrific family situation so, in my little 9' wide garage with no lift I managed to get my 81 up enough to; remove and rebuild the transmission (due to the large pump O ring leaking) I did motor mounts, dropped the oil pan replacing the gasket, went through the starter, removed all emissions related parts up top and below, swapped out the OE computer carb and distributor for a Quadrajet that has been sitting under my bench for over 25 years. Removed and rebuilt the trailing arms with new bearings etc, all new hard and soft brake lines and any and all rubber bushings back there was also replaced and I took the original leaf spring to my local "Chester Springs" to be rebuilt. Also a new Y-pipe and two new mufflers. There was a lot more I performed including a new receiver dryer for the AC I however, did not replace the AC hoses because the 134r charge was holding for many years (regretting that now because obviously it leaked out from somewhere). And I installed a new radiator. Many years back I pulled the heads to be refreshed and installed new lifters and a cam with a little more 'bump' to it. The car now has some 145,000 on it, as of the past 6 years I barely put 100 miles a year on it (taking care of my 91 year old father was priority, he recently passed)
The Tuesday after Memorial Day I'll be doing something that goes against my way of doing things and that's taking my 81 to a shop where a mechanic that works on the 'older cars' will be doing the steering box, rag joint and there is an upper A-arm bushing that is squeezing out. He'll also inspect any tie-rods etc and I'll have him dig into the AC stuff.
Unfortunately, without a lift and a decent size shop to perform the needed above work my body just can't perform the type of work it even did a few years ago.... but... I'll always do what I can.
It's sad that everything we need for our old vehicles most likely comes from China, our outlets for quality parts is indeed grim. Same goes for my older Harley.
I'll be starting another thread/topic for the steering box, I know Gary rebuilds and blueprints them 100% and I wish I was able to use his skills on my original box. I just can't tie-up the shop having my Vette sitting there whaiting for a steering box for who knows how long. 'Corvette Paramedics' about 45 miles away is my closest resorce for Vette parts. That have a decent reputation for having or getting the better of the aftermarket 'junk' that's out there.
Thank you again for all the hands-on experience and knowledge you have shared... it really is a wealth of gold you're sharing, 'if' you discover a short cut to tie into the AC fuse I'll absolutely take it.
this picture is from back in 2014 when I started all the underside work I mentioned above. I still have those wooden towers I built, they should make for a nice bonfire, I hope to never need them again and whats funny, I don't recall the engineering
Wheel Tire Vehicle Car Motor vehicle
Automotive tire Motor vehicle Gas Bumper Machine

nightmare of how I even got my car that high off the ground to use them! lol
Thanks, Ray




Gear Bicycle part Wood Material property Crankset
Automotive tire Automotive lighting Hood Motor vehicle Tread
Vehicle Car Vehicle registration plate Automotive tail & brake light Automotive lighting
 

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Awesome pictures and 'if' by looking at your pictures it appears the heaters core may be accessible from the right side of the dash area and obviously behind the glove box. I'm not sure 'if' by your pictures the center gauge cluster and the large center defroster vent section would also have to come out... but hopefully my original heater core somehow out lives me, and I won't have to dig into that project.
With 'any' of my vehicles, motorcycles and speedboat I'm all about general maintenance and trying to keep-up on things. 2014 I needed a major distraction from a horrible and horrific family situation so, in my little 9' wide garage with no lift I managed to get my 81 up enough to; remove and rebuild the transmission (due to the large pump O ring leaking) I did motor mounts, dropped the oil pan replacing the gasket, went through the starter, removed all emissions related parts up top and below, swapped out the OE computer carb and distributor for a Quadrajet that has been sitting under my bench for over 25 years. Removed and rebuilt the trailing arms with new bearings etc, all new hard and soft brake lines and any and all rubber bushings back there was also replaced and I took the original leaf spring to my local "Chester Springs" to be rebuilt. Also a new Y-pipe and two new mufflers. There was a lot more I performed including a new receiver dryer for the AC I however, did not replace the AC hoses because the 134r charge was holding for many years (regretting that now because obviously it leaked out from somewhere). And I installed a new radiator. Many years back I pulled the heads to be refreshed and installed new lifters and a cam with a little more 'bump' to it. The car now has some 145,000 on it, as of the past 6 years I barely put 100 miles a year on it (taking care of my 91 year old father was priority, he recently passed)
The Tuesday after Memorial Day I'll be doing something that goes against my way of doing things and that's taking my 81 to a shop where a mechanic that works on the 'older cars' will be doing the steering box, rag joint and there is an upper A-arm bushing that is squeezing out. He'll also inspect any tie-rods etc and I'll have him dig into the AC stuff.
Unfortunately, without a lift and a decent size shop to perform the needed above work my body just can't perform the type of work it even did a few years ago.... but... I'll always do what I can.
It's sad that everything we need for our old vehicles most likely comes from China, our outlets for quality parts is indeed grim. Same goes for my older Harley.
I'll be starting another thread/topic for the steering box, I know Gary rebuilds and blueprints them 100% and I wish I was able to use his skills on my original box. I just can't tie-up the shop having my Vette sitting there whaiting for a steering box for who knows how long. 'Corvette Paramedics' about 45 miles away is my closest resorce for Vette parts. That have a decent reputation for having or getting the better of the aftermarket 'junk' that's out there.
Thank you again for all the hands-on experience and knowledge you have shared... it really is a wealth of gold you're sharing, 'if' you discover a short cut to tie into the AC fuse I'll absolutely take it.
this picture is from back in 2014 when I started all the underside work I mentioned above. I still have those wooden towers I built, they should make for a nice bonfire, I hope to never need them again and whats funny, I don't recall the engineering View attachment 105393 View attachment 105394
nightmare of how I even got my car that high off the ground to use them! lol
Thanks, Ray




View attachment 105395 View attachment 105396 View attachment 105397
Great story hamerDown! You are the classic enthusiast! I spent most of my life doing exactly what you are doing in an equally small garage. It's only in the past 6 years or so that I finally was able to get a shop like I always wanted. You are doing great work, keep it up as long as you can!
 
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