kevinparton

The car is a 1986 N/A with 150k miles.

I've searched for threads and already have an idea what might be causing this. This is what is happening.
I fill my radiator at the filler neck housing. I take out the small plug at the top of the radiator and fill until coolant comes out the plug opening. I put the plug back in, put the radiator cap back on, check the level in the coolant overflow tank and drive the car. After about 20 miles, the "add coolant" light comes on. I stop the car. Coolant is flowing out of the overflow tank. I let the car cool. The overflow tank is now full to the very top and my radiator is about 1 quart low. I repeat the process and have the same result.

I have replaced the radiator cap with a new 13lb cap. I changed the thermostat from a 195 to a new 180. The
temp gauge holds steady at the 1/4 mark. I can drive
hundreds of miles with the radiator 1 quart low and it seems to stay at the same level. There does not appear to be an excess amount of smoke at startup. It starts easily and runs well.

Any ideas?

DragonRx7

It sounds like a blown coolant seal...but it's not smoking

Mine did the same but it smoked on start up. As long as you're absolutely positive that it's not overheating, then, it sounds like it should be alright. If it's something else then somebody else should tell you. I'm stumped.

kevinparton

Well, there is a bit a smoke on startup. But it isn't any worse than it was 6 years ago. The car is definately NOT overheating. I drive it to work 22 miles each way. A week or so ago I drove it about 120 miles with no overheating. The light comes on, but goes off sometimes for 30 seconds or so. And of course, the overflow bottle will overflow if I keep the radiator full.

kevinparton

An update. My coolant light stayed on 22 miles from work to home. It went off when I got on my street, but came back on a few seconds later. I found that I could rev the engine to 2500-3000 rpm for a few seconds and the light would go off. Let it idle the light came back on.

I would really appreciate some advice on this one. Maybe I would get more responses if I asked what color should I paint the car or if I had a poll for what type of oil everyone uses.

Tom77

I do have the same issue on my T2. It seems to me that it's working best with the radiator only 1/4 full. With a full cooling system the coolant is pressed outside. But due to less coolant level interior heating is interrupted all the time. If it's overheating, higher RPN's are helping most the time (Cabin heating starts working again, too). Unfortunately I have killed one rad until now by overheating too long. Thermostat and rad changed, but issue still occurs.

BigTone

I am sorry it really sounds like a blown coolent seal and there really is no easy fix for that.

J-Rat

iTrader: (2)

You guys probably have blown coolant seals... Here is the check:

I think my engine has been overheated. How can I check to see if the coolant seals are good?
Fill coolant system ALL THE WAY UP (engine cold). Make sure that the fluid level is as high as you can get it. Leave the filler cap off. Remove the EGI fuse. Crank the motor (it should not start). If you get a LARGE amount of coolant coming out of the coolant fill, its safe to assume your coolant seals are blown. Also, a good indication is a fuel/exhaust smell in the coolant.

Digi7ech

iTrader: (1)

Bad seal.

That is EXACTLY what my car did.

It lasted 20,000 miles before it finally let go. In between that time I drove 32 miles one way to work each day and even drove to SevenStock!

The clincher was the one day I was stuck in stop and go traffic on the highway. I guess it put too much strain on the system and it died. The temps skyrocketed past the H in seconds.

A temporary fix is to run a higher psi cap. Save for a rebuild though!!!!

I was stranded on the side of a road for 3 hours waiting to get towed home. It eventually blew a seal so bad in the rear rotor that it would only run if I pushed started it.

I know this isn't what you want to hear but make sure you have atleast 2k ready for it. If you have some more $$ then you can think of it as the car saying it's time to go TURBO! hehehe.

BTW my car NEVER smoked and even passed emissions through this period. When it finally let go it would send out a cloud of white smoke that could conceal a house!