Join Date: Jun 2008
Location: Rijeka, Croatia
@ waldowales: unfortunately, in this backwater a-hole of the world parts I don't have access to block tester, best thing I have will be leakdown tester as in a few days when I put one together. But if leakdown doesn't show anything I will order block tester online, tho.
@ sfair: Can't say I'm 100% sure about that, TBH, but I am pretty convinced it is pressure (not very scientific, sorry). Thing is, when I open the cap I get some bubbling in the overflow and little coolant spray from rad cap hole (not much because coolant level is low at that point , but more like residual coolant that was left on the cap itself or something). Also, if there is vacuum instead of the pressure , shouldn't then the coolant from the overflow move to radiator? I am mechanic by trade (sadly, I do not work in my profession so lot to learn) and I know that it shouldn't be possible for pressure to remain in the system, that is why am so confused.
Few new points, yesterday I took the bike for a spin again, wanted to recheck compression test just in case I messed something up, engine hot, 200psi both cyl, coolant level did rise few mm's, hoses were pressurized. Checked coolant leven in radiator, was missing small amount, filled it, started the bike without the cap to see if I would get fountain (friend had bad HG on his Honda and that would happen when starting it without cap), everything was fine, few air bubbles escaped, filled the rad to the brim, closed it and left the bike to idle, it was nice and hot outside, hoses were pressurized (all the same),fan kicked in, I could sense the pressure in hoses lower slightly and temp reducing (before fan hoses were to hot to hold, after it you could hold them for few seconds). let it idle more, fan kicked little later again, so that works fine. Didn't notice any bubbling in system, flow still visibly good. What I did noticed is that if I blip the throttle wide open, I will get pressure blowing in overflow, I can see bubbling inside it, but coolant level was the same, tried it few times, same result. Then I let the bike cool down and level dropped to where it was before the ride. oh, yeah, I checked the overflow hose for blockage, of course, no problem there.