79 115 Evinrude fuel blow-back

tks1954

Cadet
Joined
Jun 4, 2001
Messages
6
I posted a question concerning this some time back. I have a 79 115 Evinrude that has fuel blowing back out of the carbs. The engine starts and runs fine. After running a full throttle for a few minutes, the engine is coated with a mist of fuel from the intake ports. I have rebuilt the carbs, checked compression (105# on all cylinders), removed the intake manifold and checked the reed valves. I can find no problem. Any ideas?<br /><br />Thanks for your help. :confused:
 

jegervais

Chief Petty Officer
Joined
Jan 18, 2002
Messages
646
Re: 79 115 Evinrude fuel blow-back

Fuel blow back is usually a leaf valve, leaf plate gasket or warped leaf plate issue. Have they (the leaf valves) been replaced or removed/re-installed recently? They could be over torqued. Otherwaise, did you check the leaf plate with a straight edge?<br /><br />-John
 

rwise

Captain
Joined
Jul 5, 2001
Messages
3,205
Re: 79 115 Evinrude fuel blow-back

tks1954<br />I will agree with John, check the reed valve, it must be letting air/fuel back through!<br />Richard
 
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