While replacing my water pump this next week I am going to also replace the thermostat. The GM thermostat is manufactured for 195 degrees, but I am considering going to either the 160 or 180 degrees thermostat sold by Dr Rebuild. But can anyone tell me if they have run their engine at the lower temperatures and if so, is there is any reason that I would want to keep the operating temp up at the 200 degree level? This is a stock L-48.

Also, while doing this job I am going to boil out the radiator and replace all the hoses and belts. Any comments?

Thx.

 

CharlieS,

I did the whole radiator, thermostat, hoses thing last year... and it really did pay off. I now run about 180 all the time. I did elect to go with a 180 degree thermostat just to get things moving sooner.... and also elected to replace the radiator with a 4-core Modine. Nothing but cool running now. Good Luck

 

Regardless of which temperature thermostat you choose, would purchase
one locally as will probably be cheaper than ordering one from a corvette
specialty supplier.
Have been running the 160 degree thermostats as like the cooler running
engine and less likely to knock (ping) as at a lower temperature.
Also gives a little cushion if you get stuck in traffic on a hot day, since
the water temperature is lower.

 

Thanks guys for the comments. I think I will go with one of the cooler thermostats based on your comments.

What is your feeling about a new Delco water pump versus an off brand. I can get a new off-brand pump for $26 and the new Delco is $93. Am wondering if I am just buying a name or is there a real difference. Do you think there is any value in having my original one rebuilt and keeping it on the car? This isn't a concours type of vehicle but it is all original with 26,000 miles.

 

I am currently running without a thermostat due to a particular issue. My car runs at 160 all day long during the summer in NC. For cooler winter driving, I plan to install a 180 thermostat. During cooler months, the warmer engine will help with flow of oil. No need to run at 195 degrees. My machine shop mechanic informed me that fuel injection engines need warmer temps but a carb engine can run cooler with no ill effects. Hopefully I will have my oil temp gauge installed soon to tell if running 180 has much difference on oil temp versus 160.

I own a Frankenvette with parts from many years, so I never concern myself with originality. In your case, you may want to rebuild you water pump. If I had only 26,000 miles I know I would. Probably would not cost more than a high quality new pump to rebuild and know you have it all original.

Regards,

Jim

 

First, let me point out that I live in Florida. This summer I flushed my system, replaced my radiator seals, put 15% anti freeze / 85% distilled water and one bottle of Water Wetter (as recommended by Red Line), and replaced my T-stat with a 160* stat. I went from consistently running 220*-230* down to 160* or BELOW in the middle of Summer in Florida. That being said, I am now replacing my T-stat with the 180* T-stat because the car runs TOO cool. Optimum operating temp is more around 180*-190*. In summer it was running 160* (too cool) and now that temps are in the chilly mid 70's during the day and down into the 60's in the morning, the car struggles to hit 140*-150* (WAY too cool according to the gauge). I do think the car feels more sluggish at these low temps even though you'd think it would "pep" up with the cool air induction. My suggestion would be to make sure your radiator seals are there and in tact. They are usually deteriorated or missing. This will go a LONG way towards reducing your temps if they are too high. Then, I'd go with the 180* stat. If 160* is too cool here in FL, I would think it would be WAY too cool for TN. Running cool is fine, but you CAN run too cool.

That's my $0.02 and I'm sticking to it.

 

Suggest you install a Robert Shaw (balanced thermostat) from Auto Zone, and that you use the 180 degree temp. unit. Much has been written on this topic, and after veiwing all the information, I believe 180 is the best for most street driven, mostly stock C-3s.

 

i run a 180 stat with Modine brass radiator,shroud seals in place and run 180 all day long a little hotter in 95 degree weather but not much.

 

I have received some excellent comments and I appreciate the input. I have decided to go with the 180 degree thermostat rather than the cooler 160. I will go with a new Delco water pump and save my original one for some future buyer to have. The radiator comes out tomorrow if I can get that last transmission cooler fitting loose. You would not believe how long I have spent trying to get the darn thing loose. :cuss

 

If you are going to replace the water pump go with the Stewart water pump, its about 70.00 with a much higher flow rate than a stock water pump. their website is full of useful information.

 

Thanks Yogi78, I looked at the Stewart website and ordered one today along with their modified thermostat 180 degrees. Looking forward to getting things back together.

:seeya

 

you know i did all the the things you guys mentioned i installed a stewart water pump i recored my rad (4cores) but it still ran around 220 deg. I finally installed a 160 deg. t-stat. now it ran around 160- 180 deg. way better go with the 160.

 

O​​​​​ I have a 79 Corvette with a 69 Camaro Z28 Chevy 302 engine and I'm having problems with it overheating

 

23 year old thread might not get the response you need. Might I suggest that you start a new thread with your situation and see if the folks in here can help you.

Elmer