Expansion Tank question!

[R1Dude]

Hi all, as I pulled over at a friends house last night one of the lads spotted water coming out from the front drivers side of me car, after further inspection I saw where the water is coming from, its coming out of a rubber grommet at the base of the filler neck on the expansion tank, my question is this: should there be anything in this grommet or do I have a serious problem! all advise will be greatly appreciated as this is the first fault I have had since owning her and I can`t sleep!! :Thumbs-up

[MillSpeed]

Hmm, I\'m pretty sure the pipe from the AST is supposed to go through that grommet. The pipe itself should be connected to a long plastic "straw" (for want of a better description!) which passes through the grommet and down almost to the bottom of the expansion tank. Damn, can\'t remember if there\'s another overflow hole at the top of the expansion tank and my 7\'s about 40 miles away otherwise I\'d check! Anyways, your expansion tank shouldn\'t be overflowing.....check your AST cap to make sure the return valve is opening freely.

[R1Dude]

Cheers bud will check that now:cheers

[rx7veilside]

that grommet does not have any pipe going in or out of it and if it is overflowing then the system may be overfilled or u could have a problem

[oldone]

Let\'s hope you just overfilled the sysytem..:2eek

[gsb876]

If you overfill the system the excess coolant/water will come out of the expansion tank as at the top there is alittle hole for this exact purpose, if you wanna see where it is then fill it up and watch the water come out.

When the car warms up obivously the water expands and thus will rectify the problem by letting the excess flow out of this here hole.

Gurj :cool

[R1Dude]

Okay lads this is the situation now, filled it up, water came out the little hole with the grommet in it, took her out, warmed her up, give her some stick, after about 20 mins warning light came on and buzzer sounded saying low coolant level, water temp stayed at around 85 degrees oil temp did shoot up very quickly to 98 degrees but then came back down to about 85 - 90 degrees almost immediatley, tootled back home water level was low,topped it up again, no visible leaks, oil level was about halfway between min and max so topped it up, not sure if the water and oil can mix if a seal goes on these engines but no white sludge in oil, my fan controller was set quite high so not sure if that could have caused this abrupt turn of problems but turned it to a lower setting anyway. Also checked the return hose from the ast to the expansion tank, no blockage there, "why does the ast say never remove on the cap?" not sure what to do now as I still new at this, engine has done around 8k since rebuild and I have looked after it, please help as I have only had her for about 3 months and I not happy at the mo :cheers

[MillSpeed]

Did you happen to notice any coolant gettin pushed out of the expansion tank before the buzzer sounded? Check the return valve on the AST cap, it might not be letting the coolant back into the system when the engine cools. Might be worth just getting a new cap first as last as they do get tired over time and lose the ability to hold their rated pressure. Ignore the warning not to remove the cap!

[slippers]

Please dont take this the wrong way but which reservoir are you filling up?  The middle (the correct one), the drivers side expansion tank, or the ast?  I got confused when I first had mine as to which should be used.

Also the system can get trapped air in it that seems to be a bugger to get out.  i know when I had some work done on my engine it took about two weeks of letting air out of it to get it to drive for more than five minutes without the coolant buzzer going off.

Also if the coolant filler cap is old and on its way out this may cause a problem, something woth investigating.

Dont know if this helps but good luck.

Regards
Jon

[R1Dude]

Eeeeerm I bin filling up the expansion tank, I now see the error of my ways on that one, just seems a bit weird why its pushing the water out of the overflow hole on the expansion tank (before the warning light and buzzer come on), I am praying that I havn`t blown a seal, other conclusions are that 1. the thermostat is knackered 2. the water pump has gone, could I be right? I have checked the pipe coming from the ast to the expansion tank, it seems clear but u never know it might be buggered, cuz I know jack about these cars at the mo. lol.

p.s. the temp has never gone over 100 its only hit 100 a couple of times and that was when I was stuck in traffic

p.p.s To add to injury my clutch has stuck to the floor a couple of times, think this is the release bearing, anyone know where to get one and/or how to change it? All help is much appreciated. Ade :Thumbs-up

[MillSpeed]

Sh*t, how low was the water in the engine filler neck? The last thing you want to do is run these engines short of water. If the expansion tank is too full, when the coolant starts to travel from the engine as part of it\'s normal operation it\'s gonna overflow. It should be just over half full when cool (well as long as the coolant level is above the bottom of the pipe that drops down into the tank). It\'s not so much the overflow pipe you should be looking at it\'s the AST cap itself, just change the cap before you start worrying about water seal failure.

[R1Dude]

This is another weird thing, i took the main filler cap off and I couldnt fit any water down there, its like the engine is completley full of water but for some reason the expansion tank is overflowing and the low water level sensor is coming on after about 25-30 mins of driving, I have ordered a new ast cap just in case, I was thinking about flushing the cooling system out and replacing the thermostat cuz that mite me knackered, (is it ok to flush these engines out?) I`m assuming the water pump is working ok, because it still takes the same amount of time to warm up as its done since the day I`ve owned her. Was going to get her booked in somewhere but with the clutch release bearing now buggered looks like its trial an error, thanks again for all the advise. Ade

[Rixio]

Mine does the same thing & has been doing for a few weeks in this hot weather...

Iv changed the thermostat + AST + filler cap + flushed it about 50x!!!!

[R1Dude]

Gunna do all thet this weekend, gunna pinch me mates compression tester n check that too, just so I can start sleepin at night!! savin up to get the outside finished don`t wanna pull the engine already, but if it is a seal its gotta be done, keep on praying it isn`t. One thing I have noticed the water in the expansion tank is clear but the water in the system when I take off the filler cap is green, is that right? or have my brains been scrambled with all the stress?

[Rixio]

Mines going brown! Even leaves a brown residue on the expansion dipstick...