Hi Guys, since getting road legal i've been out on small trips to iron out the gremlins, all is fine apart from i keep blowing the expansion hose off the expansion bottle, i thought i'd sussed it by putting a different radiator cap on, but it still seems to be over pressuring any ideas? Roger
BTW it's a zx9r 1998c

[Edited on 28/7/07 by rpm]

Any diagrams, temps etc might help.

basically the expansion pipe comes off the thermostat housing and runs to the alloy tank fixed to the bulkhead i have a pipe off the bottom of the tank "t-ing" into the pipe which runs to the rad. the thermostat seems to be woking ok, i'm getting water circulation so the pumps ok, the temperature will hold at about 85-90 degrees unless in traffic then the fan cuts in so thats about right it's just that after a run of 5-10 miles especially if i've given it a boot the small expansion hose pops off sprayig water all over the engine bay. i've just changed that pipe as it seemed to be almost melting and sliding off the tank so i'll see if that helps tomorrow

What sort of clip are you using on the expansion tank? Also is there a lip rolled onto inlet tube to the tank? Remember when at temperature the system is up to 0.6 bar to 1 bar pressure ( 10psi to 15 psi) so unless there is something serious holding hoses on they will come off!

Caber

Your expansion tank should span opposite sides of the water system so that you get water flowing through the tank.
The larger bottom tank outlet should be T'd in your lower hose that returns from the rad to your engine.
The smaller top tank pipe should connect to your thermostat outlet, or top of rad, or any top hose on the outlet from the engine to inlet of rad.
I may have mis-read your reply, but the way I read it is that your expansion tank is in the same half of the system instead of across it?
Your tank should also be the highest point.

[Edited on 28/7/2007 by nitram38]

thanks for the replies chaps, i've checked the bottom hose and it tees' into the top pipe going into the rad so that could be the problem, i'll change it and hopefully that will be a fix ATB Roger