Can anyone please help me.
for the past two weeks, every morning when i start the car, my add coolant buzzer goes off. i top it up everyday before i drive off. i have an aluminium ast. it is at the same level as the main filler neck.
i checked the ast cap, which is aluminium, and it seems to be ok, (spring and the rubber thing underneath is fine) how will i know if its dead??
someone said something about its bar rating, 1.2 bar etc..? why is this so crucial?? and apparently if is too low/high system will push coolant out? am i right.
also sometimes after a drive, i can see some water on the floor, is this normal or a leak?
You have a leak, no car should lose water externally...
No you need to find where it\'s coming from... Have a \'SEARCH\' on here as there are many threads on external water leaks and where to look and suggestions....
Good Luck
depends also wher the water on the floor is....sometimes the system will dump water outof the overflow tank near the drivers side headlight
Get hold of a new AST cap, they\'re not expensive. It should be 0.9 bar, though I believe some people on here run higher rated caps I always understood this not to be recommended. You\'ll need to order a cap from a rotary place, if you go into Halfords asking for a 0.9 cap for an RX7 you\'ll get a blank stare.
As mentioned, if the water loss is on the driver side front it could be being pushed out the expansion tank. Get a torch and look down to the side of where the long neck joins the tank. You should see a black rubber grommet, if water is being dumped out here you\'ll notice it straight away. If it is, it could be anything from a dodgy AST cap to an indication of more serious problems (i.e water seals on the way out).
Might be worth replacing the cap on the filler neck (the non-springed cap) too.
Quote from: teabaggerYou\'ll need to order a cap from a rotary place, if you go into Halfords asking for a 0.9 cap for an RX7 you\'ll get a blank stare.
Any decent motor factors (not halfords) will stock a universal jap car rad cap which will fit a rx and is rated at 0.9 bar. Otherwise i\'m sure one from a mazda 626 also fits.
Don\'t wanna sound all grim reaper or anythin but this is exactly what i was experiancing and i changed the ast cap and it sorted it.... for about 3 weeks, the engine is now out ready to be rebuilt due to water seal failure!
Hopefully yours is just a faulty cap!
replace all rads caps (filler neck and AST cap) and refill the system.... run the engine to normal working temp, then leave to cool... check water levels...
top up if necessary... run to temp again.... the expansion due to the water temp should pass water into the expansion tank (and possibly overflow if there\'s too much)... when it cools the AST will draw water back in the system to the right level...
if it is still having problems, then you should get a pressure check on the system, to identify leaks...
mine has had the same problem for ages, and it woud seem to drink water.. always needing topping up, then overflowing... I\'ve replaced both caps and am just bottoming out if i have a leak.. :Viking