Hi all,
was driving the car today for a reasonable distance and when i turned the car off i could hear a hissing from both caps (filler and ast) and coolant was being pushed out of the filler cap. it then sounded like they were sucking back air into the system through the same too places. ive also noticed that the expansion tank is very full so would i be right in thinking this is all related??? :mmmm
nick
How old are the two caps - first thing to do would be to replace these if they haven\'t been done in a while
:( Mine Expansion tank got full, then started coming out of the overflow then I got a £6k bill :( :(
ah oh now im worried!?!?!? two caps are probably quite old as they were on the car when i got it imported. Forgot to mention that i constantly watch the pfc for water temp and they have never exceeded 98oc the whole time i have owned it.
i have seen on a few other threads that the hissing has happened to a few other people in the hot weather. is it common?
will get some new caps and try them and hopefully (fingers crossed) will sort the problem!.
nick
you may be ok mate. But the temp thing doesnt mean its ok either though. Mine didnt overheat at all at first. I used to park it up, come back to it 20mins later and find a pool of water under it - it had been coming out of the expansion tank. changeed the cap on the AST first off. Seemed to fix it for a week but it started again. It did eventually start overheating - Water Seal failure. I was given a tip that gives a good idea if a seal has gone:
Take the rad cap off, let the car run and warm up - if the water starts spurting out its not lookng good - suppose that shows the system is pressuring up
^ Ditto.
I found that eventually it proved difficult cooling the temps even whilst travelling along the motorway. But all is not lost yet.
Quote from: \'M@r{\']
Take the rad cap off, let the car run and warm up - if the water starts spurting out its not lookng good - suppose that shows the system is pressuring up
When you say \'spurting out\' do you mean like a fountain? If I start my car up with the rad cap off, the water level slowly starts to rise and would eventually overflow if I didn\'t put the cap back on, but I would have thought this is what you would expect as the water is starting to heat up and expand and the water pump is starting to pump the water.....I hope it\'s normal anyway!!!!
Change your caps as first port of call, it has cured some, and not others. If it does not cure, get pressure test done, and you\'ll have 2 new caps for your rebuild.
http://www.rotaryart.uk.com/acatalog/New_3rd_gen_engine_perf_tuning.html
mine is definately not coming out of the expansion tank at the moment only out of the caps but i will keep a very close eye on it.
mark - on your little test mate, do you mean remove the filler rad cap or the ast rad cap?
and in follow up to adrian\'s question, would it spurt out a lot or just overflow as i would have thought this was normal too.
leave the ast cap and only fill the middle cap (thermostat housing)..the level will rise with the cntre cap off as water pump is running and the thermo does have a small hole in it..but it shouldnt ise fast and spurt out until warm when it starts to expand
AST cap on, Fller cap off. Its ok just overflowing, its if it starts spurting out, volcano stylee I think that means you have \'issues\'!!
Quote from: Jovic82mark - on your little test mate, do you mean remove the filler rad cap or the ast rad cap?
and in follow up to adrian\'s question, would it spurt out a lot or just overflow as i would have thought this was normal too.
okay thanks for that chaps. i will get some new caps and try
here are some pictures of my caps. they both seem to be pressure caps and i thought that only one should be (the ast)??
tthere are very slight differences. on the one on the right hand side, it looks like the larger rubber has come away from something. what you guys think? this was the one that was leaking!
anyone know what the part numbers for the two caps so i can order up from mazda?
Cheers
Nick
That doesn\'t look right....the normal filler cap doesn\'t have a spring but the AST does....looks like somebody\'s fitted the wrong cap.
Yes def wrong, fit the ast with the pressure cap (spring) does it say what pressure it is, if someone has got it wrong on the caps they may also have it wrong on the pressure of the cap. It should be 0.9 bar on the cap with the spring. The place were you fill it should have no spring.
update, got the new caps and everythings looks to have sorted itself out! pheww!
i burped the system and let it settle and topped it up to the correct levels.
The expansion tank was very overfull so i removed the excess and left it inbetween full and low when cold. was it okay to do this?
Cheers
hmmmm, noticed a bit more coolant on the floor tonight. i think i may have worked out where it is coming from. it no longer leaks from the caps, the new ones have sorted that out. but it looks like it may be coming from a thinnish pipe that runs off the top of the expansion tank. it doesnt just let water out by the tank though (like an outlet), this pipe runs right across the engine bay(along the engine crossmember) to the other side of the car i think and has what looks like a join piece in it that could be leaking? does this sound normal?
was hoping to get the car mapped soon but im not gonna bother if the engine is shagged!
any help is appreciated
cheers
~Nick
anyone ???
It is sounding like the familiar coolant seals that have gone - but your best option is to get the coolant system pressure tested.
It may not be the seals though: lots of things can make it appear that way. I know Martiny had similar issues, but i think his is going ok now.
The pipe you are discribing sounds like the ast, the caps that have now sorted your pressure problems out is now settling the water/pressures in your coolant system, you will probably find that its now pressurising itself and will only allow x amount of water in the system. It does this by pushing water to the ast and if that over fills it sends it back to the overflow tank (plastic tank by drivers headlight), if that over fills it will chuck it on floor.
A pressure test would be the quickest and easiest way to put your mind at rest, or providing you are not getting the buzzer on and keep an eye on levels, I would just keep an eye on it, fix the joint if you think its leaking from there and let the system settle itself, which I have had myself and has taken sometimes 2-3 weeks to do.
RX coolant systems seem to be easily upset and can take a while to get the balance back, some cars do it almost immediately.
thanks nik and gary, that explains a few things. the car does seem to run fine still, no smoke etc and starts fine hot or cold. the buzzer has not come on yet which i know can be the start of problems. i wouldnt say there was a lot of coolant on the floor, maybe 1-2 tablespoons but you never can tell if there was more as it may have evaporated on a hot journey.
i will arrange apressure test for the car asap to sort things out. if the seals have gone or are going what would be the result of the pressure test?
Thanks for the help guys
Nick
Quote from: \'M@r{\']Take the rad cap off, let the car run and warm up - if the water starts spurting out its not lookng good - suppose that shows the system is pressuring up
thanks for that mate, i checked mine today all fine
just did it aswell and no bubbles at all! just very slowly started overflowing but def no bubbles!
yup yup same here:) just started raising up clean
ok getting a similar prob on mine, dime bar here thought I had a water leak a couple of weeks ago but realised its prob just my air con cooling down :rolleyes: anyway, after topping the coolant up and going for a run etc I popped the bonnet and I can feel coolant seeping (not pooring) out of the AST cap. dont think anything is coming from the filler cap though. So you think just replacing the AST cap will resolve my probs or is it something else like someone suggested an air lock. I c0cked up a few weeks back, checking my coolant etc and I topped it up via the AST and not the filler neck :rolleyes: would this have made a lock somewhere in the system? just a thought.
Thanks
update:
as i said before i done the bubble test and absolutely nothing was coming up. took the car for a run down to brighton and when i parked up the temps were at about 93 degrees. i turned the car back on about 2-3 mins later and the temps had risen to around 112 degrees , so i left the fans running and she came back down after that. my question is that - is it usual for it to rise that much that quickly once turned off? or would be this be evidence of seals failing? (i still have not lost any more coolant and had no buzzer yet!)
obviously im concerned that if i turn the car off and it reachs a temp above 117 degrees, then it is going to totally cook the engine!
cheers
Nick
yeah thats just heatsoak, its normal. Just make sure you dont hammer it until it reaches a normal temp.
cool cheers mark, was going to do a complete coolant change and flush as it looks like the coolant is very very thick. might just be worth starting a fresh. has anyone ever used shell glycoshell?