k, this symptom started few months back, and I just thought it was a small leak. My coolant warning light comes on every few weeks and I check the resevoir and it's full, but the radiator is pretty low, so I fill it up with water and it's fine. few weeks later, the warning light n buzzer goes off and look in the radiator, once again low. there are no spots under the car, but I have noticed a small crack in the overflow hose going to the resevoir from the radiator....but i dont think it's that significant.. could there be a deeper problem? I think i read some where that there's a tendency for rotarys to have coolant leak into the motor.. could this be the case?

Eddie

 

sounds like you have the dreaded coolant jacket o-ring failure, if you can't find coolant anywhere. have a competent mechanic do a coolant system pressure check. the cooling system should hold the pressure with out the needle dropping. have them leave the tester on the car for a few hours. you can also test for exhaust in the coolant.

 

Take out the exhaust manifold and check for water or coolant by mannually turning the engine. If you find any water in there, take the engine out and have it fixed. Would not be a bad time time to overhaul the engine.

 

it could be that your cap isnt working right and is allowing coolant out into the res but not back into the radiator.

Justin

 

i had the same problem and found that by replacing the thermostat and both caps fixed it

u might want to try that. im not saying its gonna work but its cheaper than the other stuff and a whole lot quicker

 

I have an '87 TII which was doing the same thing (losing coolant with no spots on the ground etc. . I eventually found that the o rings that go between the intake manifold and the "block" were leaking (in fact they had completely disintegrated). The O-Rings are there to block off one coolant passage and the other one is where the coolant goes to the turbo but it has to go through the flange of the intake manifold. The coolant was pooling on top of the lower intake manifold...had to look in there with a flaslight...close to the injectors. The coolant was evaporating so there was no trace left of it. There was also coolant dripping onto the turbo from the same source above...this left a white powdery residue. Although it sounds bad it was a cheap fix (less than $20.00 for the gaskets and o-rings if you can do it yourself).

Let me know if you need help diagnosing this.

Todd

 

Another possible leak could be the hose running from the rear housing to the throttle body. I checked everywhere for a leak, had the car on lifts and everything but couldn't see where it was coming from. The hose is almost not visible. It is basically behind the engine. Really sucks to replace it. It is a very tight spot.

 

Check the floor up near the heater box, could be heater core going bad.

PaulC

 

Check ALL your hose connections. After driving your car, check under the car for any signs . Check the water pump as a small leak will not be obvious. There is a peep hole under the pump. If there is a leak, you should see a white residue. Another test which will tell you if you have an O-ring failure (cross your fingers) is take off the radiator cap and crank your car. If coolant flows out you have an O-ring failure. The coolant gushing out depends on the condition of the O-ring.
Look around the engine and check for obvious white residue. You can also buy coolant leak test at stores which is a fluorescent under lighting.

 

Alright, here's what you do.

When the motor is cold, top off the coolant. Then leave the cap OFF and let the car idle to normal operating temps.

Look closely to see if there are bubbles coming out.



Also, is the overflow always full to the top?


Good Luck

13BT powered
Caprice Classic
22" wire wheels
street port
T78
Haltech

 

Just to clarify...the O-Rings that IWNTA20B was referring to are not the same O rings that I am referring to.

Todd

 

this will tell you if there is exhaust gasses in coolant
you can also get a tester from parts store to measure HCs in coolant