Gasoline in cooling water Honda BF100 four stroke

yeahoner

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Aug 13, 2008
Messages
5
I have recently gotten an old (1980's) BF100 working great for about a week. Yesterday it began hard starting a bit. Then once idling (a little spray of starting fluid and drained the float bowl) it runs great but created a gas slick on the water. I thought it was coming out in the exhaust so i re tuned the carb. Runs even better now but still fuel slick. Isolated the source to the water outlet (slick goes away when oil zorb pad is held in the path of the water). Carb is not clogged. nothing is coming out the float bowl drain tube. Is it possible this is from a bad intake manifold gasket? This seems to be the only logical place that unburnt fuel could mix with the cooling water. It also seems that this would be putting water in the cylinders though and i'm not having that problem. Any help would be appreciated. I will probably be changing this gasket this afternoon. Thanks
 

hondon

Lieutenant Commander
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Jun 11, 2001
Messages
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Re: Gasoline in cooling water Honda BF100 four stroke

Carefull here. The crankcase breather hose exits at that same grommet so if you have excess crankcase pressure via blowby from a tight valve or stuck rings you will get that slick.Do a leakdown test.
 

yeahoner

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Aug 13, 2008
Messages
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Re: Gasoline in cooling water Honda BF100 four stroke

I had the valves done two weeks ago. by my local honda shop. (i had a stuck exhaust valve) how do i do a leakdown test?
 

yeahoner

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Aug 13, 2008
Messages
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Re: Gasoline in cooling water Honda BF100 four stroke

i disconnected the breather and no fuel there, also checked re routed the water, only to find that I had been mistaken, slick still forms with water going elsewhere. I think the fuel is in the exhaust now.
 
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