Ok I was topping up the coolant, as my low coolant alarm came on. Whilst topping up it seemed to take more than I was expecting, then I here a trickle noise. (Check pants and no I haven’t wet myself) I then see a puddle of coolant on the floor. Damn! Upon further investigation I found that the coolant has gone back into the expansion tank and started to overflow where the expansion tank neck joins to the expansion tank. Little bit confused as I thought that the filing point should fill to the top, without back feeding into the expansion tank. Any input would be greatly appreciated.
Thanks Adam
leave the pressure cap on the AST tank and make sure the engine is cold and then fill up...only from the filler neck.
where are you filling it up?
If you are filling it at the Engine (next to the alt) it shouldn\'t drain back (as long as the caps on the AST), if you are filling the AST it will only fill the expansion bottle if its too full (the overflow is at the top)
Another thing to check is that you have the caps on the correct way (sprung one on the AST and the flat one on the Engine)
The engine is stone cold. It has an after market ast tank and the cap is on. Im filling it from the engine point near the alternator. Don’t see why it should have filled the expansion tank up.
Cheers for the input guys J
make sure all the hoses are attached right way round on that after market AST and are free flowing.
Is the coolant coming out the top of plastic can?
there is a hose coming from the filling point and going to the top of the ast and a hose going from the middle of the ast to the top the expansion tank. sound right?
i think i may have discovered why the expansion tank has back filled, me being a pleb!
yeah its coming from the top of the plastic expansion tank.
check the ast cap hasn\'t split as this could cause the system to send coolant into the expansion tank.
here is a pic of my ast tank cap. pull the lever and turn the cap but it doesnt seem to want to come off and i dont want to force it.
http://i106.photobucket.com/albums/m256/pigeon_07/27102007555.jpg (http://i106.photobucket.com/albums/m256/pigeon_07/27102007555.jpg)
That cap rating looks wrong to me, think it should be rated at 0-9 twist off type, but cant really see what alloy AST you have, i think
16 lbs is a bit too high, may strain water seals!
just my 2p!
sounds like the Cap/AST to me, have a good look at the ast, make sure there is a clean circle where the Cap has been sealing. Also make sure the cap is not damaged or too loose.
If you are filling at the engine with the AST cap on there usaly the AST cap stops it draining back into the Expansion bottle, so i would suspect the problem is to do with that.
Do you still have your stock AST? if so put it back on and see if it still does it. Its not a new problem with alloy ast\'s allot of people would rather fit a New plastic one rather than an aftermarket alloy one.
Quote from: pigeonthere is a hose coming from the filling point and going to the top of the ast and a hose going from the middle of the ast to the top the expansion tank. sound right?
nope
hose from top of ast should go to overflow as the cap controls the overflow.
Does sound wrong But if the cap is on why is the water getting into the AST if the pipes are the wrong way round?
Have you fitted a New AST? I am assuming you put the pipes back as you found them?
nope i bought the car with the alloy ast on it already so dont have the stock one.
think i have sussed it though! the pipes are on the wrong way around! thanks to all for your input.:cheers
I had a similar problem, went crying to rxmotors, Ian changed the caps and was perfect ever since? The seals had swollen apparently, and weren\'t keeping pressure...