89 L-98 coolant problem
Thread Starter
Drifting
Joined: Mar 2007
Posts: 1,295
Likes: 326
From: Central Pennsylvannia
2021 C4 of the Year - Modified Finalist
89 L-98 coolant problem
My car warmed up this morning, went a few miles, pulled into a parking lot, when i came out of the store, coolant was overflowing from the overfill tank.
car does not run hot, i took it home, lifted the hood, the overfill tank was normal, but a minute later i could hear it blowing coolant back into the overflow tank? then it filled the overflow tank back up again.
Waited about 30 mins, checked the overflow tank and it is about 3/4 full of coolant,
Coolant is good, clear, green, just put new fluid in it a month or so ago,
I read some other theads, but wanted to mention the car is not overheating, but the low coolant light did come on.
Oil looks good, no white frothy goop on the stick.
what do you think can be the cause?...thermostat? head gasket?
No other leaks have been found
Thanks
car does not run hot, i took it home, lifted the hood, the overfill tank was normal, but a minute later i could hear it blowing coolant back into the overflow tank? then it filled the overflow tank back up again.
Waited about 30 mins, checked the overflow tank and it is about 3/4 full of coolant,
Coolant is good, clear, green, just put new fluid in it a month or so ago,
I read some other theads, but wanted to mention the car is not overheating, but the low coolant light did come on.
Oil looks good, no white frothy goop on the stick.
what do you think can be the cause?...thermostat? head gasket?
No other leaks have been found
Thanks
Team Owner
Joined: Sep 2001
Posts: 62,140
Likes: 1,728
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
You should burp the system first, then see what it does. Probably should replace the cap as well if it hasnt been done in a few years.
Thread Starter
Drifting
Joined: Mar 2007
Posts: 1,295
Likes: 326
From: Central Pennsylvannia
2021 C4 of the Year - Modified Finalist
Not sure how to "burp' the system, i did take the cap off, noted it was low, put some 50/50 mix in, while the car was running, bubbled out of the radiator like mixing vinegar and baking soda.
theres air coming from somewhere, never seen one do that...
theres air coming from somewhere, never seen one do that...
Drifting
Joined: Apr 2007
Posts: 1,339
Likes: 2
From: port charlotte fl
Could be head gasket.Depending where they let loose it's quite possible to pressurise the water jacket without getting water in the oil.Sounds like you have the better of the two scenarios.A failed stat should shoot your temps up if it's stuck closed.
Last edited by staugur; Sep 26, 2007 at 02:47 PM.
Le Mans Master
Joined: Dec 2000
Posts: 7,839
Likes: 22
From: San Diego, Ca
Either the thermostat is stuck closed or it has a blown head gasket. Since you've lost coolant in the past, I would explect the latter. All most every '89 seems to go at #7 so pull that plug and check for rust on the threads. You can also crank the engine over by hand until the #7 piston reaches TDC. Any coolant will then flow out through the plug hole.
Thread Starter
Drifting
Joined: Mar 2007
Posts: 1,295
Likes: 326
From: Central Pennsylvannia
2021 C4 of the Year - Modified Finalist
Result are in, no blown head gasket, seems as though i may have let air in the system, I followed Vader's advise and "burped" the system, no more back flow in the overfill tank.
Thanks for all your help!
These cars can be very sensitive to everything. Took it for a 80 mile run, no overheating, no leaking, although the "low Coolant" light kept going on and off..but the overflow tank has plenty of coolant, checked it last night after it cooled down, radiators still full.
Kept my eye on the temp gauge, never went much above 190.
and the old L-98 still pulling strong, love that car!
Thanks for all your help!
These cars can be very sensitive to everything. Took it for a 80 mile run, no overheating, no leaking, although the "low Coolant" light kept going on and off..but the overflow tank has plenty of coolant, checked it last night after it cooled down, radiators still full.
Kept my eye on the temp gauge, never went much above 190.
and the old L-98 still pulling strong, love that car!
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Result are in, no blown head gasket, seems as though i may have let air in the system, I followed Vader's advise and "burped" the system, no more back flow in the overfill tank.
Thanks for all your help!
These cars can be very sensitive to everything. Took it for a 80 mile run, no overheating, no leaking, although the "low Coolant" light kept going on and off..but the overflow tank has plenty of coolant, checked it last night after it cooled down, radiators still full.
Kept my eye on the temp gauge, never went much above 190.
and the old L-98 still pulling strong, love that car!
Thanks for all your help!
These cars can be very sensitive to everything. Took it for a 80 mile run, no overheating, no leaking, although the "low Coolant" light kept going on and off..but the overflow tank has plenty of coolant, checked it last night after it cooled down, radiators still full.
Kept my eye on the temp gauge, never went much above 190.
and the old L-98 still pulling strong, love that car!
