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engine blowby

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davomoto
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Post by davomoto » Thu Sep 23, 2010 7:13 pm

Happy to help!
davomoto
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mike1969
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blowby

Post by mike1969 » Sun Sep 26, 2010 11:55 am

Got the motor assembled and back on the bike. I'm happy to say that the blowby is gone!

Thanks to everyone who helped with advice.

I still have to re-torque the head bolts.(thanks for that tip also)

mike1969
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blowby

Post by mike1969 » Sun Oct 10, 2010 12:05 pm

Sonofabitch! I thought all was well with the Dream. I took it on an extended ride this
morning and the blowby is back with a vengence!

I can feel air blowing from the crankcase vent hose from 5 inches away at idle.

Everything is back together correctly(rings etc.)

Is there a possibility that the oil pump is putting out too much pressure?

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davomoto
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Post by davomoto » Sun Oct 10, 2010 8:45 pm

Mike, no these oil pums have minimal pressure.

Davo
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mike1969
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blowby

Post by mike1969 » Mon Oct 11, 2010 6:53 am

Thanks Dave,That eliminates another possibility.

Any suggestions?

LOUD MOUSE
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Re: blowby

Post by LOUD MOUSE » Mon Oct 11, 2010 7:21 am

Ya did install the 2 gaskets and metal plate at the top?. ............lm

mike1969 wrote:Thanks Dave,That eliminates another possibility.

Any suggestions?

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Snakeoil
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Post by Snakeoil » Mon Oct 11, 2010 8:45 am

I would expect there to be significant air flow out the breather hose of a running engine. The crankcase is a sealed vessel of varying volume, and breaths thru that hose. No flow thru that hose means you have a hole in your crankcase somewhere. If there is no smoke coming out of the hose and your compression test is to spec, I would think you are good to go.
regards,
Rob

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