weak spark?

racerone

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Lack of oil is one of the main reasons !-----This motor needs to come apart !
 

cesandroid

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Strange since I've been running the vro as well as 50:1 in the tank. You'd think it have lots of oil. Only other thing is if it was running lean on all 3 cylinders. What else would cause lack of oil?
 

Bosunsmate

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Strange since I've been running the vro as well as 50:1 in the tank. You'd think it have lots of oil. Only other thing is if it was running lean on all 3 cylinders. What else would cause lack of oil?

bad crankcase seal
 

cesandroid

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Are you referring to the upper and lower seals or the seal when its split?
 

racerone

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What brand of piston ?------Part # ?-----What size was cylinder bored and honed to.------Example is 3.020" --------Or something else ?
 

cesandroid

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Like I said before they are wsm pistons and rings bored to the max, 3.040.
 

cesandroid

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Wonder if it can be honed with new rings and get the shop to take it apart and put it back together? They could pressure test it too I believe. Would hate to discard it with all the work that was put in. If not than it would need sleeves to start over. That's pricey.
 

Bosunsmate

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Are you referring to the upper and lower seals or the seal when its split?

All the above but if its all cylinders then its could be the crankcase halves seal
Im not sure if youve solved the initial spark query or you are adding that to cost of repair too
 

cesandroid

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Well the spark issue I can't test when hot yet because I have the head off. Its all 3 cylinders that are affected. The spark did appear OK cold but maybe it was leaking air and running lean causing misfire especially the hot start scenario. What should compression be on these motors when rebuilt say before break-in?
 

cesandroid

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Hmm interesting, I took the compression reading when it was put back together, I figured that was a bit low but wasn't sure. Well I'll touch base with the machine shop that did the work and see what they can do.
 
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