I've got an 86 that I can't seem to keep cool.

A little history.. Rebuilt the motor, slightly larger cam, changed to AFR 190 aluminum heads, custom prom burnt, MSD ignition and rebuilt the trans.

The problem...When my engine temp gets hot (usually after driving long enough to get the engine oil hot), the water temp will rise when I'm at idle or a very low speed and only cool down when the speed picks up.

New... The radiator was replaced with an OE replacement, switched to a hi-flow Steward water pump (then switched back to an OE when it didn't help), added an additional electric fan in front of the ac condensor.

Consideration ... I've been looking at getting a DeWitts all aluminum 2 row radiator ($500), putting the hi-flow pump back on with a new thermostat.

Question ... Has anyone gone through this and what did they find worked the best to keep their car below 220 degrees?

 

Hey, question, what temp are you runnin' under?

Codes?

Location of your driving?

Air filter type?

Thermostat type/temp?

Might need more info, that's all

Just trying to help[sm=icon_cheers.gif]

 

I actually haven't driven the car in 6 months or more. I live in Michigan and we have a big event called the Dream Cruise coming up in 2 weeks so I thought I'd get the car running again.

The only temps I can tell you come from the dash, I've seen it climb over 230 or more if I'm at idle (after the car gets hot). I'll have to look through my paperwork to determine the thermo temp ~ but I'm sure it's whatever brand the large auto parts chain carries. The air filter is just a fram, nothing special.

Some other mod's I've done: Hi volume fuel pump, hi-flow MAF, performance (main) cat with race "y" pipe and aftermarket exhaust.

This car was a project car that I was really into for a while, then the kids came along and the money quickly was diverted towards the house and other items. This is kind of a "reserection" of the old 86 - I'd like to get it back to an occasional driver.

Any help is appreciated!

 

Keep in mind that you do NOT want that engine to run too cool.[]

I know, sounds crazy, but it has something to due with wear on the cylinders or something.

Search this site. There were some lengthing discussions about this issue in the past.

This advice came from one of the VERY knowledgable members (Tech Certified I believe)[8D]

Might have been Leesvette or Mech259. Not sure though.

Look it up and repost the link for everyone.

If not, let me know and I'll try to find it...

If you want[sm=icon_cheers.gif]

 

230-235 is not that uncommon. Those temps are abouty right. You fans should kick on close to those temps and cool it down some. I think your okay.

 

If the fans were successfull in bringing the temp down, I'd be ok with 220 or 225. Although after it's been driven for a while on a hot summer day, if I get caught in traffic - there have been times I've had to pull over and shut it down after clearing 240.

I've contacted Stewart regarding the hi-flow water pump and moving fluid too quickly. Their response was that was a myth, in addition - they suggested I get a hi-flow Robert Shaw thermostat (it will have holes drilled in it for by passing).

I had also read that aluminum heads have smaller water jackets than the cast iron ones I pulled off. I've tried several times to reach AFR (Air Flow Research) and have gotten no response.

I know that Corvette's run a litter hotter, but if the oil temp gets hot and the fans aren't bringing the temp's down - I gotta think it's the radiator.

 

I'm glad this topic came up. The reason why, I just had the whole cooling system replaced on my 85. I was concerned because the car used to run between 195 and 207. Now it runs between about 207 to 227. I called my local corvette specialty mechanics shop and he said that I was fine. His words to me were that these cars were designed to run between 220 and 240. My fan kicks on at 225. I put a 192 thermostat put in, a new cooling fan, a new radiator and new water pump in it. Seems to run fine, just a little hotter than it used to.

 

Holes drilled in a thermostat is one of the most outlandish things you can do. Its useless and causes more problems than it could possibly cure. You will freeze your 'nads offin the winter.

 

Interesting thing - I could solicit 25 different people and get 15 different answers.

I can't imagine a few small holes would cause heat failure, perhaps delay the warmth to the cockpit, but who caresit's a Corvette not a 4x4 - it's parked in the winter (here in Michigan).

Clayton - I'm really surprised someone suggested your car should run up to 240 (normally), if I'm not mistaken the car will display the red warning light at 240 or 245 - at least on my 86.

I thnink I'll go with my gut and replace the parts that make sense logically. I'll post the results, probably early next week.

Thanks.

 

If holes improved the function of the thermostat then all manufactures would drill them in theirs, correct?