My FD3S overflows antifreeze when parked hot after being driven
Everyones input can be correct. Unfortunately I had the same symptoms, and I just kept filling it when it was cold every morning, but it got worse over time. I tried replacing things here and there, and like you though it could be my overflow, but in the end my coolant seals were the culprit.
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~Insane Burnout
Joined: Mar 2008
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It is wise and cheaper to replace the AST cap and the fill cap before a tear down to replace the cooling seals!!
I just removed the AST cap and although it looks ok the rubber gasket is creased and probably does not seal properly. The fill cap looked like **** so I replace it as well tomorrow, I hope the dealer has these in stock. I'm also replacing the hoses from the AST tank to the fill cap and all the way to the overflow tank. If the OF tank is cracked due to old age I will replace it as well.
While I'm doing all this I'll be replacing the RAD hoses and all the belts.
The pully races are rusted, what do you'all think, do they need to be replaced??
I just removed the AST cap and although it looks ok the rubber gasket is creased and probably does not seal properly. The fill cap looked like **** so I replace it as well tomorrow, I hope the dealer has these in stock. I'm also replacing the hoses from the AST tank to the fill cap and all the way to the overflow tank. If the OF tank is cracked due to old age I will replace it as well.
While I'm doing all this I'll be replacing the RAD hoses and all the belts.
The pully races are rusted, what do you'all think, do they need to be replaced??
I had a thermostat that was sticking shut, not opening at the right temp. I could drive for a short distance, but when I came back, I would be missing coolant. After doing several "experiments" with the bad thermostat, here is my personal conclusion as to why this happened: the w/p would try to generate pressure, but the sticking t-stat would stop that pressure at a "wall". This was obvious when my fully-pressurized/warmed up coolant system was still cold on the hose from the filler neck to the radiator. The system must have become so pressurized that it would open the rad cap, pushing coolant into the overflow. When the overflow would... overflow... I would lose coolant.
Make sense?
Make sense?
To be on topic....I just bought my FD and its leaking coolant. The previous owner replaced the overflow tank. My friend and I checked out the car yesterday and the previous owner put in way too much coolant because he said it was leaking out. Okay so we do the pressure test on the radiator and there are no leaks, we suck out some coolant so its on the full line ( not over full ) and as I was driving...it beeped like mad crazy telling me to add coolant but its already full. So replacing a thermostat and radiator/ ast cap will solve my problem? I added coolant but it doesnt seem to be sucking into the engine. Im talking about the little resevoir on the right. Please help me guys and sorry for being a noob......
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~Insane Burnout
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I dont know which place you are refilling your coolant, but I always took the cap off the housing and filled it there, all while squeezing the radiator hose to get bubbles out. I had really good results from a new AST cap w/red lever on it. Get it hot and vent it, no more air in the system.
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~Insane Burnout
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Originally Posted by nokiafan88
I added coolant but it doesnt seem to be sucking into the engine. Im talking about the little resevoir on the right. Please help me guys and sorry for being a noob......
He says "Im talking about the little resevoir on the right", so I'm guessing he means *his* right when he is standing in front of the car... which means he is probably talking about the AST.
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~Insane Burnout
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Left side of car = Drivers side
Right side of car = Passenger side
If this is the reservoir he is talking about, it's on the left side..
Last edited by 93RX7-europa; Apr 6, 2008 at 05:03 PM.
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From: Long Island,NY to Orlando,FL
Thread Starter
~Insane Burnout
Joined: Mar 2008
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From: Off the grid
I think he is looking at the front of the car, again to top of your engine you need to add antifreeze on the fill inlet cap side where the Tstat is and NOT the AST tank.
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From: Oregon
sorry to be so stupid but ill try the AST cap and Radiator cap. The previous owner has a radiator cap with a spring under it. I dont think the radiator cap is suppose to have that after reading the big fat fd coolant thread
As I stated before, either side works. I usually fill the *lower* point first, then close the lid, and fill the higher point. This is so the gravity doesn't pull the excess coolant down to the lower location and cause it to spill. You can only fill the AST as high as the hole in the top that leads to the overflow.
The cap on the AST *MUST* be pressurized (needs a spring cap)! This is VERY important! The cap on the metal coolant filler neck that has the long hose that connects to the radiator does not, it is just a "lid".
