Mot Aborted Over Heated Water On Floor Please Help !!!!

[gonzodave]

I took the 7 for its mot yesterday and mot station rang saying nearing the end of the test water started to come from front driver side of car (guessing expansion bottle) and it started to steam aswell so turned off car and aborted mot, i took it back home topped up the water and left it ticking over, after 12-13 mins it starts to do the same thing again. This problem is only when staitionary and fine when moving. After it has squirted water from bottle the water level light comes on and temp gauge starts to rise fans do kick in but dont seem to bring it down enough, if this dont make sense just say and i will try and make it clearer, hope some 1 can help as i dont want drive it around if it goin to blow up and i need an mot asap, Thanks in advance for any help Dave.

[ashc]

could be a dodgy pressure cap on the filler neck. dont fill it from the expansion tank, it will always chuck out the excess. You dont see it whilst driving cos its all over the road!

[gonzodave]

I hope it is just a pressure cap, a mate of mine said it could be a water seal and may require a rebuild, when driving i can then stop and it will still take quite a while to start spitting out water again, could it also be a faulty thermostat ??

[gonzodave]

If nobody else has any ideas i will try the cap and maybe the thermostat and see if it helps, any more help will be much appreciated. Need to get it back within 2 weeks for my free retest,
Thanks Dave

[leon]

Check the Pressure cap on the AST to see if its faulty, Do the Champagne test and see if you are getting "bubbles" in the filler neck while the engine is running. If you see pretty bubbles you have seal flailure. those bubbles are caused by exhaust gasses getting into the coolant system. *FALILS*

if your still in doubt use one of hte dyrocarbon testers on the coolant.

[gonzodave]

Will go have a look right now for pretty bubbles :-) thanks

[gonzodave]

I had a look for bubbles and there were some, but there would be a couple then stop then a couple more then stop again, but the water level keeps dropping when the bubbles come up so would this be air lock bubbles maybe, every now and then the water would shoot up again and fall back down quickly again, i dont no if any of this helps or even makes any sense :-) just a quick question ? the filler neck cap is not sprung like a normal 1 is this right, and also the cap on ast tank is sprung but doesnt fit properly, has some body possibly swapped these over and would this even cause a problem

[Grizzly]

It may be worth just giving the system a quick check before driving it, things like.

1. Start from cold and check the Pipes don\'t go hard whist the coolant is still cold.
2. check the Thermostat by checking the rad gets hot (check in different point top and bottom) don\'t forget to not put you fingures in or near the fans as they may come on unexpectedly.
3. Make sure both fans come on when hot.
4. When cold remove the AST to overflow pipe, whist warming up on idle check if there is any leakage from that pipe (AST end ).
5. check the front Carpets inside are not wet.

If all this is good upto now.

6. Drain the Coolant overflow bottle and refill to a set level that is easy to check, use the car but check it quite often to see if it rises or falls (should stay constant)

Reading the post above, if you have any doubts about the cap fitting correctly replace them both. Also what AST are you using? if its a stock plastic one make sure there is no leakage from the seams (its quite common)

[Grizzly]

May be worth checking for water marks round joins and for bad Jubilee clips things like that (the engine to rad pipes are favorite for this)

[SmbFD3S]

Mine did the same thing as yours when i first had it, opened the AST cap to find lots of crap around the seal, so drained the coolant, flushed the system and cleaned the cap... Was fine after that

[gonzodave]

Cheers for the ideas guys i will check all these, i have ordered a new coolant cap for filler neck, and i will try find an ast one or are they both the same ?
Thanks Dave

[SmbFD3S]

They are not both the same no, the filler cap is a sealed pressure cap whereas the AST should be pressure rated at 0.9bar

[michaelb]

Gonzodave

Mate, if you really get stuck with this problem there is Powergains Motorsport in Romford and visit Kerim at the above company.  They are well knows RX7 specialist and I am sure they would sort it out for you

I will be going there probably on a Wednesday morning if could tag alone on the A12

Regards,
Michaelb

[gonzodave]

Hi guys I have just recieved my new filler neck cap and will am waiting for a thermostat to turn up, i will fully drain water and refill with fresh water and antifreeze (which antifreeze is best or just stay with whats already in it ?? ) change stat and cap and check everything for leaks fingers crossed this will solve problem. Would it be advised to flush system out with something and would this be done,
Thanks again for your help Dave.