FC overflow issue
#1
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FC overflow issue
i'm dealing with a weird coolant overflow issue.
The car is a 88 Turbo, it has a ron davis radiator, newly replaced thermostat, water pump, radiator pressure cap.
The car runs fine, and doesn't get too hot (possibly due to the huge radiator).
But sometimes, after a long drive, i would notice additional water in the overflow tank (after cooldown of course), something is causing it not to flow back to the engine.
Did a pressure test, it drops about 1psi over a 10minute period, so doesn't appear to have any significant leak.
anyone has a similar issue before?
The car is a 88 Turbo, it has a ron davis radiator, newly replaced thermostat, water pump, radiator pressure cap.
The car runs fine, and doesn't get too hot (possibly due to the huge radiator).
But sometimes, after a long drive, i would notice additional water in the overflow tank (after cooldown of course), something is causing it not to flow back to the engine.
Did a pressure test, it drops about 1psi over a 10minute period, so doesn't appear to have any significant leak.
anyone has a similar issue before?
#2
Try this:
Go for a long drive, get her nice and hot.
(After stopping) open hood, observe water move to the recovery tank, note level as it cools down.
If you think it's higher than it should be, wait overnight and with the hood open, start her up and see if the "excess" has been sucked back in.
If you haven't already, replace the tube between the fill cap and the overflow tank.
Go for a long drive, get her nice and hot.
(After stopping) open hood, observe water move to the recovery tank, note level as it cools down.
If you think it's higher than it should be, wait overnight and with the hood open, start her up and see if the "excess" has been sucked back in.
If you haven't already, replace the tube between the fill cap and the overflow tank.
#3
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/\..agree
..also mark the tank with a piece of tape to indicate level.(why mess it up with a marker..right?)
That should tell you if there is any difference in level.
..also mark the tank with a piece of tape to indicate level.(why mess it up with a marker..right?)
That should tell you if there is any difference in level.
#7
LegacyCore
This is exactly what happened to me, I was getting more coolant in my overflow tank and it was not going back into the rad/engine. Did a pressure test and wasn't losing pressure at all, no white smoke in exhaust, and spark plugs were dry. Didn't have any over heating issues and was on a stock radiator with efan. Ended up being a broken water jacket on the middle plate facing the rear. Hope this is not the case for you.
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#8
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I build a custom v-mount setup with a 16psi pressure cap.
When the engine is hot, the overflow tank level is high. Even the overflow thank is about to overflow...
When it cools down, the level drops back to what it was before.
The system is pressurized when hot.
Never seen this this happen before (but that might be because the original overflow tank isn't as clear as the new one).
When the engine is hot, the overflow tank level is high. Even the overflow thank is about to overflow...
When it cools down, the level drops back to what it was before.
The system is pressurized when hot.
Never seen this this happen before (but that might be because the original overflow tank isn't as clear as the new one).