Id have to say its likely hg. Do the check for acidity mentioned and see, also does your heater work? Most airlocks tend to be around the heater core and back of the head. Gurgling/waterfall sound could be another clue.
Hope im way off and its simple but my moneys still firmly on hg...
__________________
'89 MA70 Supra GT aero 3.0turbo JDM, Rebuilt motor, K&N intake, 3" stainless turbo-back. New turbo and braided line kit...
'89 Honda NC27 400, NC23 cams, open pipe, PC36a shock & possibly Showa USD forks...
'83 Yamaha 29R XJ750E-II, number 69 off the line, only runner in the country? Original except Koni shocks
'95 Honda PC26 CB500R, Winter hack, hateful, trying to sell it
I'm not paranoid, they really ARE after me!!! 
|