65droptop442

I have been chasing this for some time now. I bought the car last year and it had been sitting for about 5 years. It will run alittle hot on the highway 190. When you get on side roads it runs about 200. The real problem is when at idle or slow speed it will climb to 220-230. It doesn't puke but its not running cool enough. I had the radiator boiled out and rodded out. I replaced and checked thermostat 180 degree. I put all new hoses and water pump. Timing is 10 degree at idle and 27 degee at 3000 rpm. I'm lost as to what else I can check to get this to run cooler. I also flushed the block. Any help would be appreciated.

Oldsmaniac

It should cool to T stat value on the highway. You did not state your rear gearing. I would say your radiator may be too small. How many rows is it. Even though it has been cleaned you cannot see what is in there. There still could be restrictions.

oldstata

Is the fan clutch working you mentioned it get hot at idle maybe check or make a shroud to help

oldcutlass

Your timing needs to be advanced. Timing will effect idle temps. What distributor are you running? What was the outside air temp for the readings you provided? Your cruising temps are ok for a hot day. A 180 degree thermostat begins to open at 180 so 190-200 close to normal. Your low speed and idle temp is based on lack of air or sometimes water flow issues. What brand water pump did you buy? Is yours a fixed or clutch fan setup?

65droptop442

It has an HEI in it now. I purchased a new water pump from elgin industries out of Illinois along with a new fan clutch

1arunem

Have you replaced your radiator cap as well?

65droptop442

yes new cap from parts place.

65droptop442

It has the factory shroud. The radiator is the original harrison 3 row that the radiator shop rodded out and said it wasnt that bad for sitting so long.

oldstata

Just wondering if its a ac car ?

oldcutlass

Does your timing advance anymore past 3000 Rpm. If not, I'd start with bumping it up to about 17/18 initial which will bring it to 34/35 @ 3000. See what your temps are there.

68442CONVERTCO

How old is the gas in it?

65droptop442

I'll advance the timing and see what happens.

oldcutlass

The other thing is watch your vacuum advance. Some of the canisters that come with the HEI's are not adjustable, you don't want to exceed 50 deg BTDC with it connected @ 3000. Also if you hook it to manifold vacuum after you have your timing set, and readjust the idle down it will help your temp issue.

65droptop442

Thanks, I'll give that a try. The vacuum advance is not hooked up at this time. I was going to change back to a new original points distributor with a petronix ignitor. But I could not get the distributor to lift out.

65droptop442

new. I have put about 2500 highway miles on it. It runs great on highway and no overheating issues. it only acts up around town or at idle.

65droptop442

no a/c. 3.73 gears. 350 turbo trans. original 3.42 posi and jetaway.

MDchanic

The 10-15° of advance at cruise that you get with the vacuum advance may serve to cool your engine down a bit.

- Eric

oldcutlass

Sorry we lost power here for about an hour. So what is your temp going to at idle? What did you set your timing to?

455man

Dont know if anyone else mentioned it but Air/fuel mixture will cause overheating too if it's lean. Check for vacuum leaks.