94 slt 750

[keng]

i have a few questions about my ski.

its a 1994 slt 750
just blew a hole in the center piston
was informed plugs where wrong. BR9ES thats what was in it when i got it. told is needs a BPR7ES would this add to my problem.
plus was carboned up a bit. not white. as usually a hole in a piston to me is from a lean cylinder. im gonna clean my carbs and check the reads before i reaseble the engine. is there anything i should possibly check out before i get to far on the assembly and have to tear it appart again.

next thing i want to know is in regards to the jet pump.
what is the proper clearance between the impeller and the wear ring
and i was told that more than likely my impeller will wear before the ring is this true? i need to replace the impeller anyways. so that would save me a few bucks. and well saving money is what this is all about. lol.

Ken

[xlint89]

Welcome to the Hulk Keng. Holing the center piston is odd, usually it's one of the other 2. Do a leak down test to see if you have a bad gasket seal. The plugs you had in there are actually colder than the recommended 7's. Most guys like to use the BPR8ES, so I don't think those had anything to do with the problem. A clogged or dirty carb may have done it though. You should go through your carbs and inspect/clean them thoroughly. there are filters internally that may be gunked up and restricting fuel flow.

[ph2ocraft]

There was also an update on the fuel selector switch.
The center is an odd one to go, I'd be looking for a plugged internal filter and/or air leak.

[keng]

how do i go about testing for a air leak. or should i just replace the crank seals is there a gasket or a ring or sealant on the case halves? want to have this thing running top shape when im done. and what are the recomended break ins on these

[dorf]

Break-in Instructions:

http://server1.sbtontheweb.com/forum...ad.php?t=13960

[xlint89]

Seal the carbs and exhaust pipe air tight. Then apply 9 lbs of vacuum or pressure to the pulse line fitting on the block. It should hold for a few minutes. If it doesn't, there is an air leak. Spray soapy water around seals and gaskets looking for bubbles when searching for leaks. Crank seals require splitting the engine cases and there is a silicone sealant (Three Bond 1211 or equivelent) between the halves.