Compression

[TrickyNicky750]

Hi I recently received a 94 kawasaki 750 sx. It's been sitting a while. Put new plugs in it. Drained all old fuel out Of the tank and put fresh fuel in there also threw on a new battery. I put a few drops of two stroke oil and fogging oil in the cylinder. At first it didnt want to crank, I tried a few times and it wouldnt budge. I pulled the compression release and got it to turn over. I took the air filter off and gave it a few shots of starting fluid, I pulled the plugs to make sure im getting spark. Both cylinders have a strong spark. How ever no fire. My question is could the compression release have gotten stuck open and if so is there an alternative diagnosis method other than a compression check. I dont have the tool and was jist wondering if there was a quick way to see if the release is stuck open? Any imput would be appreciated.

 

[Vumad]

There is no compressio release. It is a crank case drain inczse the motor gets flooded. Most of us have replaced them with blockoff kits. There is no substitution for a compression test. You can put your finger over the plug hole but thats very specofic.

 

[TrickyNicky750]

ahhh, that makes since, I was told that is was a compression release. So how do you drain it if you place a block off kit on the machine, does it have any benefits?

 

[chevota84]

The drains can stick open and cause a lean burn down, it's a lot easier to flip the ski over on the beach to let it drain if it gets flooded than to do an engine rebuild. It's interesting that it cranked when you opened it, though. Did you notice any water coming out of it anywhere?

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[Tyler Zane]

I would put a block off plate on that crankcase drain before you try to run that engine. You will still have compression if the drain is leaking. Crankcase leaks create a lean fuel charge because there is air that's not being metered entering the crankcase. It will result in a runaway engine and eventually burnt topend.

I watched a guy rebuild a 750sxi pro and skimp on the block off plate. He rebuilt that engine again in 2 weeks....

Buy a compression gauge if you plan on keeping a 2 stroke.

 

[Vumad]

ahhh, that makes since, I was told that is was a compression release. So how do you drain it if you place a block off kit on the machine, does it have any benefits?

I have extensive experience in flipping skis over to get the water out. Got to do it many times my first trip to Daytona. I've since learned that it's best to only put fuel, oil and air into the engine, and now I have better experiences.