Hi guys! I have a friend of mine who really need some good advice. His Fd is overheating after just a few minutes from start up. The car does not smoke at all and starts up immediately when cold and warm. No bubbles are forming when engine is on either. The car still pulls very hard and seems healthy too.

Whats happening is that it just warms up and up. The fans start normally then all water is spilled out from the overflow tank. What could it be?

Many thanks in advance!

 

Sounds to me like the water pump is history........

 

thanks....but if the water pump has gone, then no flow of water right?

 

Just bought a new cap for the AST --- Useless. Same thing happened. All water went out from the overflow and overheated again!

 

anyone please?

 

Dang, sure sounds like a cap issue. There must be a pressure leak somewhere in the system causing the coolant to boil over. Although coolant would be flowing out of it!

 

I would start with a pressure test.

 

I Mahjik ! I am always happy when you post !!

You mean a pressure test for the cooling system? I read most of the threads with similar problems and apperantly the problem appears when there is an air leak in the system between the AST and overflow tank. right?

 

Well, your problem seems different than the other threads. Most people experience the cooling shooting out of the overflow after the car has turned off and is cooling. It sounds like, at least from your initial post, that this is happening while the car is running. Is that true?

If so, that's not good and really does sound like the cooling system is getting over pressurized.

 

Yes, this is happening when the car is still running. However, this happens after a few minutes that the temp is showing normal. Then the temp climbs up and the coolant is all thrown out.
I was also curious why the engine felt just a bit warmed to the touch whilst the temp gauge showed MAX.

 

It's possible that the thermostat is done and not opening. I would start there first.

 

...but if its the thermostat then the engine will be exteremly hot right? That's the opposite. I hope i'm understanding things well...

 

Not necessarily. From what you've described, I would suggestion on or more of the following:

1. Thermostat is done
2. Waterpump is done
3. Over-pressurizing the cooling system by an o-ring failure

The coolant gauge gets it reading from a sensor on the rear housing. So, if the coolant is getting hot that quick, and the fans coming on don't help; it sounds like the coolant isn't circulating through the radiator which points to the thermostat or the waterpump. You are also certain that the waterpump belt is on the right way (i.e. it's not spinning the waterpump backwards)?

 

Does the heater work? If the thermostat isn't opening, you shouldn't get much heat.

 

i had the same buzz ,changed the coolent ,problem solved do it yearly wit fds

 

The overflow of the coolant appears to back up the the temperature sensor saying the motor is over heating. If the coolant is not circulating then the engine won't get that hot to the touch before the block reaches the temperature the sensor is seeing. I would also change the thermostat while doin the water pump. The other thing that will drive up temperatures is if exhaust is getting into the coolant system o-ring or o-ring groove failure in the exhaust area. bUT i WOULD EXPECT YOU WOULD SEE THE OTHER TALE TELL SIGNS OF AN O-RING FAILURE Sorry for the caps (not retyping) You can open the filler neck and check for flow/thermostat opening.

 

Majik hit on a very possible point, as the water pump would have to have next to no impeller blabes for there to be no water flow. If your friend has installed the Greddy under drive pullies then make sure the belt is to the right of the pulley or alternator side and not on the left or filler neck side of the pulley.

P.S. Just because these gauges (water temp) rarely move off the half way point don't think for a minute that when they do move there not accurate. If you continue to heat the motor up to the temperatures your gauge is registering then you will be replacing the motor as you will warp the housings or endplates.

 

Thanks Mahjik! I try to pass your suggestions to my friend. He's quite sure that an o-ring failed However, i'm not that 100% sure. If there's an o-ring failure, does the engine compression be normal too? The car performance is stunning.

 

Thanks CantGoStraight!

You guys are always of great help! I really wish its the pump or thermostat. However, i wonder cause when we started the engine with the cap off (filler neck) the water was pushing up and down, therefore i think the pump is good too, right?

 

Yes, if there is an o-ring failure, it typically does not hurt compression tests. Pressure testing the cooling system is one of the ways to test for an o-ring failure (as well as any other possible leaks). Pressure tests are not necessarily conclusive, but they are one of the steps in troubleshooting cooling system related problems.

 

Hi Mahjik! I addressed your suggestions to my friend and booked the car for the mechanic by the end of this month. I'll keep informed what was the problem.

In the meantime, many thanks for your support !!!

 

Its been my experience that water pump internals rarely fail. Normally, when the pump starts to fail, you get an external leak. I think you have a bad thermostat. If you replace it, be sure to use an OEM unit. Many aftermarket thermostats are garbage. Don't use them!!!

 

The day my coolant seals failed in my original motor, I was running what were (at the time) my fastest ever ETs. Not saying the coolant seals are definitely toast, but I have seen a few FDs with compromised coolant seals running very strong.

 

Thanks guys!
We'll have an answer by the end of the month hopefully. I will give you the outcome for this for sure.

Should a coolant seal fail, the coolant will overflow a few moments after start up? Or it doesn't really matter? Cause my friends Fd spills the coolant out only after it reached normal temp and have risen to max temp.

 

It pukes as soon as the thermostat opens. I would bet that any pressure in the radiator side of the cooling system would make it puke.. Sounds less like an engine problem and more like someone's got the wrong cap on the AST and it isn't sealing the overflow line.