Just noticed the main radiator hose (left side from pump) goes hard and very flat in the middle when cool. Once warmed it expands round again. Otherwise everything seems ok, plenty of coolant, no leaks, temperature running fine. Is this just a hose replacement or symptom of something else? (MTS1200S, 2012, 10K miles, fully serviced) Thanks.
A sealed system pressure will vary with temperature. Sounds like your system when cold is under vacuum. Release the radiator cap when cold and squidge the pipework several times and see if that changes the rested shaped of the pipe. If it does great but if the symtom persists you have a problem that needs resolving. It will most likely be something simple and cheap but if you are very unluckly there is a remote chance it could be an early indicator of impending head gasket failure. Andy
Id say as above, sounds to me like you may have air in the system that's expanding when hot and contracting when cold, check your header tank level run it with the cap off for 5 mins then let it cool before refitting it.
Update...after speaking to ducati workshop I have replaced the hose and radiator cap. I am now trying to refill the system. I drained out 1ltr of coolant and have 1ltr of fresh approved coolant to go back in...however I have only got 1/2 ltr in (via the expansion bottle) and it is level between the min/max lines. How do I get the other 1/2ltr in? I have run it enough for the pump to circulate (only to 65 deg as I don't want to get it too hot with low coolant level...squeezed every pipe, shook and bounced it but can't get the level to drop. Is there a trick? Thanks.
You need to vigerously massage the large diameter hose, just give it a few good squeezes and you should be able to get more fluid in. You may need to do this several times. If all else fails, run the bike for a short while. Andy
Sorted...I ended up draining it again and refilling direct into the radiator. Will see if the original problem is fixed.
