Hey all, having a shit of a time with my 701. Overheated it a while back, fucked headgasket. Got head skimmed, now doesn't have a lip she's pretty flush. Anyway, slapped it all together checked it cleared fine. Didn't check squish with , went riding. Lasted 15 mins blew headgasket. Fuck! Blew in a different place, I checked cylinder was square and sleeves hadn't dropped. Was wondering if its possible the piston pinched fire ring and it blew that way? Im running 82.5mm pistons, a normal 701 gasket will work fine? Can I just double base gasket (using sealant between them) to gain clearance? This time ill measure squish! Was so pissed off this did this, was going to hit surf got in sight of the breakers...fail!
what kind of head gasket are you using? i dont know of any aftermarket brand head gaskets that have a very good track record....OEM is the way to go on head gaskets. usually the thickness of the head gasket itself shud give you most the squish you need. the piston shouldn't go high enough to contact the gasket, the edge of the piston is normally about 0.5mm below the deck at TDC....unless your cylinder has been machined down?
Not sure on the brand, seems ok thou. Better than the shitter I got with a wsm gasket kit lol lol. It's a composite one with wire reinforcement. Ah cylinders must have been machined, at tdc they protrude 1mm tops.
standard cylinder height is 119mm for reference (I think), so either the cylinder may have been machined or the top of the cases...or you have a stroker crank you can get thick base gaskets to make up for it , or cut a recess into your head.. ...oh, and your talking about to the edge of piston eh?, not the top of the dome?
Yea haha the edge. Piston is .025" over the top. Seems more machining of the head might be the best/correct idea. Thanks for your reply.
Hell yes. If your pistons are protruding from the top of the cylinder and you have bugger all squish band on your head then you'll be way too low on squish and close to deto. I trust there is no "pitting" around the edges of your piston? Measure the squish first so you know how much you need to take off the head. You can get away with putting more/thicker base gaskets in to raise the cylinder however you will lose bottom end as you raise both your transfer ports and exhaust ports.
Genuine bolts holding it together. No pitting, comp must be damn high thou! I need this fucker running! I'm letting team Yamaha down, all my mates with seadoos are mocking me!
