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Discussion Starter #1
I'm a newbie and glad to have found you guys!
Thinking about solving hot running 79. A new aluminim rad is an option but I am told that replacing the thermostat with an orifice plate may do the trick. Has anyone tried the orifice? If so, does it work? Where can I buy one? What size orifice opening,etc?
Thank you for any info you have.:buhbye:
 

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welcome to DC


first, is the car stock? doing mods to an engine will increase the heat, therefore, you will have to work on the pump, radiator, etc..

anyways, go with a stewart HI-FLOW pump for that year and engine. also, use a stewart HI-FLOW thermostat to suit. i think a 180 would be fine.

be sure your fan clutch is working right. warm the engine to normal temps, then shut off. turn the blades by hand..if they move freely then the clutch is no good.

be sure your fan shroud is in place and seated right. also, be sure that the foam inserts around the radiator are in place. add more foam if you see too many gaps. this keeps the air going thru the radiator and not around it.

be sure the radiator is clean inside and out. if you see alot of buildup inside, you can try using a flush to clean it out, or have it done professionally.

if you have a/c be sure the condensor is clear and that air flows freely thru it.

be sure your timing is right.

check your anti-freeze mixture. if adding new, add distilled water with a 50/50 mix...not more. nothing cools better than water.

be sure the radiator cap is good...15 lbs should be fine.

the stewart home page shows their pumps that are available and thermostats. they also have an excellent FAQ page that will answer many questions about an engine running hot.

www.stewartcomponents.com


doing the above should get your car running at "normal" temps. 200 degrees is an ideal running temp for that year. remember, the engine was designed to run hot partly due to the emissions.
but, you might find it running a little less than that.

my '81 used to run 230 or so, by doing the above, it's down to 205...tops..with the air on..normally i'm at 190.

hope this helped.....if you have a built engine, then you might want to look into a bigger radiator and a performance hi flow pump.:)


ps: if you meant using a restrictor plate in place of the thermostat, don't do it. they were fine as a quick fix back in the 60's but not today.
 

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mga nailed it.

My 72 was running at 230 and sometimes higher.

A DeWitts aluminum radiator, Spal fans, and Edelbrock water pump got it down to low 180's with a 180 t-stat.
 

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biltogo said:

A DeWitts aluminum radiator, Spal fans, and Edelbrock water pump got it down to low 180's with a 180 t-stat.
damn....180 isn't bad at all.

my '81 is stock, still full of emission stuff and still on an ECM so i need to be where it was designed to be. but, before doing all that stuff to it, that damn car would almost red line hot until the electric fan kicked on. now, i've yet to see it over 205 with the a/c on under any condition.
 

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mga said:
damn....180 isn't bad at all.

my '81 is stock, still full of emission stuff and still on an ECM so i need to be where it was designed to be. but, before doing all that stuff to it, that damn car would almost red line hot until the electric fan kicked on. now, i've yet to see it over 205 with the a/c on under any condition.
There isn't a thing wrong with 205. I went to overkill on mine. I know it can run cooler yet on the highway by swapping in a 160 t-stat , but that will never happen. A small block runs at best efficiency at 190 +/- 10.
 

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In addition to MGA's checklist.....also take a close look at the lower radiator hose as you rev it to 2500 rpms , at idle.Make sure it isnt collapsing thereby restricting water flow. Spend a couple dollars and take it to a do it yourself car wash and pressure wash the condensor and radiator, back and front . Id do all the simple checks and maintenance before getting into component replacements. Clean and flush the inside of the cooling system with Prestone H.D. Cleaner and open y our block drains and radiator drain too. Finally, run no more than 25% coolant to distilled water --- water is the best coolant . Add a can of Water Wetter to the system after youve done MGA's checklists and the above. Youre temps will come down.
 

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cooling them down is doable...you just have to find the right combination that works for your car and engine set up.

like i stated, mine is still stock, so i have to keep it running at the temps it was designed to run at.

i do recommend that everyone should get rid of the old water pumps and use a HI-FLOW (of your choice) with a HI-FLOW thermostat.
 

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Unless the heat rejection equipment is up to the task, no amount of GPM water flow is going to matter. Do the maintenance routines first, to be sure the heat is being surrendered up to the water/coolant. I have a Stewart pump added cause of my motor buildup over stock. Love it. High quality over stock pump.
 

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Discussion Starter #9
Thanks guys for your inputs. The engine has approx. 9000 miles since a completely stock overhaul, new water pump, new stock radiator, new hoses, new foam for the radiator shroud and fan shroud is installed correctly, the fan clutch is approxi. 6 years old, the exh. system is been checked for possible back pressure, and the timing checked. So far I have found the fan clutch to be bad and some vaccum leaks. I will keep you posted and again thanks for all your inputs. :buhbye:
 

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did i mention to be sure the system is purged of all air? sometimes a "full" radiator can be deceiving....

that too would cause it to run hot.
 

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Fine 79 said:
Thanks guys for your inputs. The engine has approx. 9000 miles since a completely stock overhaul, new water pump, new stock radiator, new hoses, new foam for the radiator shroud and fan shroud is installed correctly, the fan clutch is approxi. 6 years old, the exh. system is been checked for possible back pressure, and the timing checked. So far I have found the fan clutch to be bad and some vaccum leaks. I will keep you posted and again thanks for all your inputs. :buhbye:
Did the new fan clutch make a difference?:buhbye:
 

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Hey F 79! I forgot your email address. Send me your email address. I have some pics for you. Carlisle n' the 79 n' the '90.
Mike:thumbsup:
 

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Discussion Starter #14
Originally posted by Mike
Did the new fan clutch make a difference?

Hi Mike,

The email is [email protected] or [email protected] aol.com.

The new fan clutch was install and the clutch fan check out failed, after warming the engine at idle for 45 mins ( the mga check out was to warm the engine to normal tempatures and hold the fan blades, the clutch assy should lock the fan clutch).


Well both the old and new clutch assy were the same, they both were free. However, the engine appears to be running about 10 degrees cooler, so was it the clutch or what??????. The weather here is rainly and cool, so I was not able to do a proper road test, will keep you posted THANKS

fine 79


\\/QUOTE] :( :(
 

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stewartcomponents.com has an nice FAQ site that talks about engine over heating.

i know they want to sell a product, but it's a forum type board and many people tell of things they found or did to reduce engine temps.
 

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Fine 79 said:
Originally posted by Mike
Did the new fan clutch make a difference?

Hi Mike,

The email is [email protected] or [email protected] aol.com.

The new fan clutch was install and the clutch fan check out failed, after warming the engine at idle for 45 mins ( the mga check out was to warm the engine to normal tempatures and hold the fan blades, the clutch assy should lock the fan clutch).


Well both the old and new clutch assy were the same, they both were free. However, the engine appears to be running about 10 degrees cooler, so was it the clutch or what??????. The weather here is rainly and cool, so I was not able to do a proper road test, will keep you posted THANKS

fine 79




\\/QUOTE] :( :(
:huh: Maybe 10 degrees is enough? Hopefuly the road test will be ok. I sent the pics to your other email address. I hope yo got them?
 
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