Leaky Radiator Drain Valve

[DaveW]

Has anyone experienced a leaky radiator drain valve?

This started when I over heated on the commute the other day. Found that the water level was low. Filled up and drove. Found the drain valve was leaking.
I had to tighten... loosen and retighten the valve several times. It appears to have stopped leaking for now. This plastic valve looks a bit cheesy.

Also, when I noticed the over heating and just after I have shut off the motor I heard a hissing sound from the area between the water pump and t-stat housing. But I did not see nor have an seen any coolant. The only place I can confirm a leak is the drain valve.

I planned on flushing the cooling system this week. Just wondering if the radiator drain has been know to be a problem. Has there been any problems with leaks around the t-stat or water pump? This is on a 89, stock closed system, 140,000 miles. (let's save the conversion discussion for later)

[ACE]

Hey Dave,
I stripped the plastic drain on the original radiator on my '90 years ago and ended up just putting a bolt in it. I never drained the radiator with that anyway, I always just pulled the lower radiator hose, much faster.
If you aren't seeing any leaking antifreeze then that hissing is probably air in your system leaking by the thermostat. Did you burp the system when you refilled it?
Good luck. If you ever need another hand, I'm not far from you.

[DrMoab]

One thing you really have to watch on the older closed systems is getting air pockets in the system. They are almost impossable to get out.

If you are hearing hissing noises though you better look for more leaks. I have a bunch of parts off the older closed systems if you need anything. We have converted(saving that conversation for later) two older closed systems so we have the parts laying around.
Has anyone experienced a leaky radiator drain valve?

This started when I over heated on the commute the other day. Found that the water level was low. Filled up and drove. Found the drain valve was leaking.
I had to tighten... loosen and retighten the valve several times. It appears to have stopped leaking for now. This plastic valve looks a bit cheesy.

Also, when I noticed the over heating and just after I have shut off the motor I heard a hissing sound from the area between the water pump and t-stat housing. But I did not see nor have an seen any coolant. The only place I can confirm a leak is the drain valve.

I planned on flushing the cooling system this week. Just wondering if the radiator drain has been know to be a problem. Has there been any problems with leaks around the t-stat or water pump? This is on a 89, stock closed system, 140,000 miles. (let's save the conversion discussion for later)

[DaveW]

Hey Dave,
I stripped the plastic drain on the original radiator on my '90 years ago and ended up just putting a bolt in it. I never drained the radiator with that anyway, I always just pulled the lower radiator hose, much faster.
If you aren't seeing any leaking antifreeze then that hissing is probably air in your system leaking by the thermostat. Did you burp the system when you refilled it?
Good luck. If you ever need another hand, I'm not far from you.


I used the drain this time because I put in some preston super flush. I will be replacing the hoses Friday when I drain it.
The plug did not look stripped. Are the threads in the radiator plastic too? If so they might be stripped. If not I may just use you bolt idea.

I am thinking of converting to the open-style system old buldging hoses I decided to flush the system and replace the hoses. If it look like I still have leaks, other then the drain, I will order the new radiator and parts to convert. I understand the hoses will still work.

[DaveW]

One thing you really have to watch on the older closed systems is getting air pockets in the system. They are almost impossable to get out.

If you are hearing hissing noises though you better look for more leaks. I have a bunch of parts off the older closed systems if you need anything. We have converted(saving that conversation for later) two older closed systems so we have the parts laying around.

I have not burped the system as I only refilled with the prestone super flush. I will be draining it again in a couple of days. I am checking to see if the level drops and adding water. If my current plastic drain valve keeps leaking I may be looking for another if you have one laying around.

If I find more leaks of continue to have cooling problems I will most likely just convert to open. As the t-stat and water pump both are original those may get swapped too.

Last fall in Moab and last week are the only times I have over heated. Both time it was due to low water levels. But now I may have found the leak. If stopping the drain leak fixes thing I will keep the currrent setup for now.

I hope to test the system Saturday after the meeting. I up by the B last Saturday. I hope the warm weather melts smoe more of the snow.

[sidriptide]

what brand of radiator is it?? i just installed a new GDI from Auto Zone and i though tthe drain was closed but when i filled it it was leaking... when i tried to close it with a pair of pliers i think i broke it.. the valve lever is a large flat blade that seems to only go 1/4 to 1/2 turn... and now i am waiting for the parts store to get a new one so i can swap it for another one....

[DaveW]

what brand of radiator is it?? i just installed a new GDI from Auto Zone and i though tthe drain was closed but when i filled it it was leaking... when i tried to close it with a pair of pliers i think i broke it.. the valve lever is a large flat blade that seems to only go 1/4 to 1/2 turn... and now i am waiting for the parts store to get a new one so i can swap it for another one....

The radiator is the stock original with the plasic drain. The drain did leak some. I used a wrench to closed it as tight as I dared and it seems to have stopped or at least slowed to not noticable. Since it look about 6 months to loose enough coolent to over heat this time, that may be the slow leak that had cause the last two over heating episodes.

What did the GSI cost? Was it 2 or 3 row?

OK I'll ask... If I do decide to convert to an open system what recommendations are there for the brand of radiator? I have heard of Modine & GDI for after market. Some have even used the 92+ OEM from the stealer.

[sidriptide]

The radiator is the stock original with the plasic drain. The drain did leak some. I used a wrench to closed it as tight as I dared and it seems to have stopped or at least slowed to not noticable. Since it look about 6 months to loose enough coolent to over heat this time, that may be the slow leak that had cause the last two over heating episodes.

What did the GSI cost? Was it 2 or 3 row?

OK I'll ask... If I do decide to convert to an open system what recommendations are there for the brand of radiator? I have heard of Modine & GDI for after market. Some have even used the 92+ OEM from the stealer.

i got a 92+ GDI 3-row aluminum from autozone.. about $125.... took a lil work to burp the system but not to bad.. and i replaced it because i had the same slow leak that finaly lost enough coolant to overheat the engine... i am still working on a proper puke jug because i have a powerade bottle for now...

[DrMoab]

i got a 92+ GDI 3-row aluminum from autozone.. about $125.... took a lil work to burp the system but not to bad.. and i replaced it because i had the same slow leak that finaly lost enough coolant to overheat the engine... i am still working on a proper puke jug because i have a powerade bottle for now...
AutoZone sells those too. They are about ten bucks...come with the tube. the jug and a holder that mounts almost anywhere. My dad is using one. It works pretty well.