Coolant Overflow Bottle Overflowing

[nizmo_freek]

Hey

My coolant overflow bottle is filling up and spitting coolant out of the "hole" on the very top of the bottle.

Last weekend when i gave the car a bit of full throttle action i noticed that the stock temp gauge was sitting just between the half way mark and the full mark, so pulled over but left the car running, couldnt see any coolant spilling from any pipes anywere, but the overflow tank was completly full (didnt overflow though) so i drove the car back home very slowly.

One thing i have noticed is that when the car is up to full temp the radiator pipes are never hard (pressurised) ,in my old car the top radiator pipe would always be hard as a rock, mine is soft and almost feels like its empty, so i thought maybe the radiator cap is stuffed, went out and bought a new cap which changed nothing, pipes still soft and coolant overflow bottle is filling up.

The coolant system is always full and i check the level all the time, there are no leaks anywere at all, the waterpump and thermostat are nissan items that were replaced about 6months ago.

Any ideas what the problem could be? im thinking possibly a blocked radiator?

Any suggestions would be awsome

Cheers

[legend01]

At a guess I'd say your pressurizing the cooling system ! do you get any hydrolic lock on start up ???

[stolen_s15]

I would suggest giving your radiator a good flush. Might fix the problem

[nizmo_freek]

At a guess I'd say your pressurizing the cooling system ! do you get any hydrolic lock on start up ???

What exactly do you mean by hydrolic lock on start up?

The car starts and drives perfectly.

[nizmo_freek]

I would suggest giving your radiator a good flush. Might fix the problem

Yea i might give that a go tomorow, the coolant is starting to get a little brown.

[nizmo_freek]

By the way, i forgot to mention that after the stock water temp gauge went between medium and high i went home and plugged in my power fc (still on the stand base tune) and went for a very slow/quiet drive , the water temp sat on 95deg most of the time, which seems a bit high to me?

[Doctor 30]

I have the same problem except mine just blew the radiator recently. Get under the car and check for leaking welsh plugs. I replaced the radiator cap and kept topping up the motor and flushing it until I realised it was a stuffed welsh plug which would suck air back into the motor which caused a massive pressure build up when I turned off the motor.

(I happened to accidently pop mine into the block so I wouldn't do what I did to repair it)

[crack]

thermostat may not be opening fully or siezed partially open

[Devils_Advocate21]

change the radiator cap?

[-_-StRyDeR-_-]

he has already changed the cap. what about a air lock? when you go out to the car of a morning (or anytime where the car has sat for 6-9hrs) is there anything on the ground?? leaked coolant? trace it back to where its comming from.

1. get your radiator flushed (specially with summer now)

2. check all welsh plugs and hoses for leakes

and hoses arnt spose to be rock hard, go to repco or somewhere and feel new hoses

[666DAN]

I've had 2 cars that have done this, it was headgasket both times.

[nizmo_freek]

he has already changed the cap. what about a air lock? when you go out to the car of a morning (or anytime where the car has sat for 6-9hrs) is there anything on the ground?? leaked coolant? trace it back to where its comming from.

1. get your radiator flushed (specially with summer now)

2. check all welsh plugs and hoses for leakes

and hoses arnt spose to be rock hard, go to repco or somewhere and feel new hoses

The car never leaks coolant ever, the only time it has leaked coolant was yesterday when the overflow oveflowed lol.

I will give the car a flush today and change the coolant

I meant the hoses are spose to be hard when the car is at full temp and the coolant system is pressurised, lol , but mine are always soft when the car is at full temp, probally because most of the coolant run into the oveflow tank and then overflow, hence not much pressure in the system because there is hardly any water actually in the motor.

[nizmo_freek]

I've had 2 cars that have done this, it was headgasket both times.

I hope not lol, but somehow i dont think so, as the car isnt blowing any white smoke, its not losing coolant apart from when it spews its out the overflow, the car still runs perfect.

[nizmo_freek]

thermostat may not be opening fully or siezed partially open

Thermostat is about 6months old and was a brand new nissan item which was replaced when i got the waterpump/cambelt etc etc done.

[rb26s13]

pull your radiator out and get it flushed professionaly at radiator shop(tanks off and core cleaned out properly!) or buy a new radiator

[nizmo_freek]

Looks like i may have found the problem!

Took out radiator and the top and bottom radiator hoses today, coolant was suprisingly nice and clean, but the top raditor pipe was full of rusted metal crap, the big nipple on the intakemanifold were the top raditor hose connects to has rusted away at the front of the nipple (see pic) which has obviously been rusting for a while sending rusted grunk crap threw the motor/radiator etc etc, which has probly blocked the radiator causing the car to overheat, the bottom of the overflow tank was full of brown rusty water which i didnt spot before hand.

Possibly one of the previous owners didnt use antifreeze, or not enough antifreeze which has caused the steel nipple on the intake mani to rust pretty quickly, hence causing my problems.

I will try and give the nipple a bit of a clean up and get most of the rust off, then flush the whole system heaps times, instead of get the stock radiator flushed/cleaned i might get an alloy one instead (will help with cooling when i start doing some track racing) ,and some new coolant ofcourse, i will update this thread when i have everyhing back together and hopefully fixed.

Pics of rusty nipple!

Cheers for your help

[nizmo_freek]

Turns out the radiator isnt the problem (i dont think).

Got the car running tonight (new alloy radiator and coolant) and had it idling while i was toping up the radiator wating for the thermostat to open, the car was idling for atleast 20mins, but the thermostat never opened, the water level of the radiator hardly dropped even when the car was up to full temp, the bottom radiator pipe stayed cold so im guessing the thermostat isnt opening.

That should have been the 1st thing i shouldve taken out and tested, i just ruled it out because its only about a year old genuine nissan item, not sure how it can all of a sudden go faulty, seems weird to me, the car was running fine and didnt overheat after nissan had replaced the thermo,waterpump/cambelt etc etc.

Anyway, what brand of thermostats do you guys use? im not really to keen on getting another nissan one if its just going to go faulty again (i bought the nissan thermo in the 1st place because if thought it would be the most reliable one, i guess not).

Cheers

[Spoolup]

you have a blown headgasket

[nizmo_freek]

you have a blown headgasket

Why do you say that?

The car does not blow white smoke, it does not use water, there is no oil in the water, there is no water in the oil and the car runs perfect! i dont have any of those issues.

[Owgasm]

My radiator cap is the wrong size thats why my flys off. But i need a larger radiator cause my car at times heats up and pops the cap and then bubbles out.