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2016-08-06 KZ1300 Gas In Crankcase



2016-08-06 Gas In Crankcase

This is a gas tank. A gas tank that doesn't vent all that well. That's why the cap is open now.

This is a 37 year old petcock. Above it is a full 5+ gallon gasoline tank sitting in a shop with 100F+ temperature. PV=NrT. 

This is the hose that connects the crankcase to the air box. Crankcase vapors get sucked into the air box to make cleaner air for the state of Kali.

..and this is the result of a gasoline flooded crankcase. Note the evap rate has already lowered the level by an inch or so. About 1 gallon of oil. About 2.5 gallons of gas.

The old gurl wouldn't crank. Pulled sparking plugs. No fuel in top end. Huh?
Go change water. Find a lot of gas on the ground. WTFO? Mop up gas.
Drain float bowls.

What's that dear? You need help in the house? Ok, I'll help.

Return to shop. WTFO? Gas all over the ground. 

The moment of realization. Remove air box cover and filter. Gas, about 1 inch up from filter bottom. Sick feeling. Did I kill this engine by spinning it and trying to start it? Thank goodness I did not use ether or something equally stupid to try and start her.

Oh, and the clutch lever now goes back to bar. What's up with that? Really bad feeling.

Drain oil. Remove filter and oil fill cap. Use compressed air to evap as much gas as possible.
Refill with oil. Used same filter, dried out. It was new just 10 minutes ago. Remove plugs again. Spin motor using starter to distribute oil to crank plain bearings and engine top end.

Not a good day.
Drain oil, replace filter, fill with new oil. Don't have any cheap oil, so Delo it is.

Start, she sounds a bit rough, but not horrible. No low end thumping from crank. Cams talks happily. Maybe I'm OK. Call it a night. 
The clutch is still not happy. To bummed to call Ray and tell him I probably just destroyed his beautifully crafted engine. Fuck. Just F U C K.

Removed clutch cover. Check out how dry the friction disc is.

Disassembly pix for later install. No scarring. So far so good. But why no clutch lever?

Part of the disc is entirely dry. Could it be it was above the gasoline level?

Of course, by now, the bike is drenched in oil, my lift is a mess and you get the overall picture.

Soaked the plates in oil for > 24 hours.

Re-installed oiled up plates.. 
..and all is good! Clutch is back.

Could it be the cork based material needs oil to 'swell'? 
Test ride proves all is good, clutch wise.

Telling a buddy at work today about it.. and the clutch lever going to bar for no good reason. His first statement "Did you flood the crankcase with gas? Happened on my Suzuki liter bike once."

Called Ray, he doesn't expect any damage to the engine. Something about how folks used to drain then fill crankcase with diesel for cleaning. That residual oil would still be in the filter and oil pump while I was spinning the engine to clear the top end. She did run, for maybe 5 seconds or 10 seconds max with combustion. And not all cylinders were firing. More like an occasional pop.

So there it is.

Ordered new OEM friction discs, just in case. Minimum spec, per FSM, is 3.2 mm. I measured each disc in 4 quadrants, my minimum was 3.45 mm so these discs are most likely OK. If so, then great, I just got a good deal for a fair price on consumable parts that might not be available in the future. 

Also ordered a 12 Vdc fuel cut off valve. 
Looking at a new Pingel petcock with adapter plate. I am not a purist.

..and got to look at why the tank does not vent well. This has been a problem since new.

So, there it is. I'm not going to pull the engine down to 'inspect'. I'll run her and see what happens.

Wish us luck.



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