# 8n running hot/booking gas



## woodie (Apr 29, 2006)

Hey all, my 8n (160 hrs on rebuild) has been running hotel than normal lately when under pro load, about 10-20 degrees. I found that it is boiling the fuel inside the tank which has never happened before. I had a leak at the corner of the manifold gasket, which I thought was the issue, but replacing the gasket did not fix it. Any thoughts.

Thanks,

Woodie


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## woodie (Apr 29, 2006)

The subject should read boiling gas not booking. Sorry, using the cell phone app for the first time.


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## jhngardner367 (Apr 5, 2011)

How is the water pump working ?
Also, were the cylinders bored much ?
Timing,and spark plug gap ok?
Has it got the vertical,or horizontal exhaust ?
All these can affect engine temps,and vertical exhausts can raise fuel temps.
Ours,on the farm used to,until my uncle R.G. made a heat shield for it.


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## BigT (Sep 15, 2014)

Hello woodie,

I'm thinking that you may have a cracked exhaust manifold, or a leaking exhaust gasket. Maybe not getting torque to the exhaust gaskets??

Also check your point gap. If the points are too close it can affect timing, and cause excessive exhaust heat.

Another possibility....it might be the winter blend gas/ethanol mix. I have read that the winter blend can reach boiling point faster??


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## jhngardner367 (Apr 5, 2011)

BigT is correct,and the winter blend / summer blend is one point I forgot about!
That's one thing that affects all engines,since fuel stations / suppliers try to sell off the remaining blend ,and it can cause problems !


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## woodie (Apr 29, 2006)

Thanks gents, I'll look at everything you said. I'm also thinking maybe the thermostat might be having issues. I don't hear the water pump whining and I retorqued the manifold bolts, it should be good. I wasn't aware of the gas blend issue. Thanks again


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## Ricknott (May 15, 2016)

Yes timing can cause it I am having same problem


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