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Gas spits out of carb on saw when running

Efisher26

Efisher26

Tinkerer
Joined
Mar 29, 2016
Messages
1,066
Location
MA
Echo 290evl, was given to me, runs, good compression, but gas spits of carb when running, is it an adjustment or do I need a carb kit?
 
Rio95

Rio95

ArboristSite Member
Joined
Mar 7, 2016
Messages
81
Location
Melbourne
That is a sign of a worn piston skirt - being a piston ported engine (I think), it is not sealing off the intake port adequately as it compresses the crankcase, causing back-flow through the carb.

I had a weedeater blower with the same symptoms, and a new piston fixed it.
 
HarleyT

HarleyT

Tree Freak
Joined
Dec 6, 2014
Messages
17,677
I thought it would be a reed valve engine, but Mike Acres says it is piston ported. http://www.acresinternet.com/cscc.n...0847ffc412ae6e7e88256d0c006b8c60?OpenDocument
If it is a reed valve engine, it would most likely be a broken valve.
Well, I haven't worked on one, so I don't know personally. I would suggest going through the carb anyway, it is probably overdue. Diaphrams are likely stiff and not working properly, needle might be a tad leaky, a new kit would likely help.
And while the carb is off, take a peek in the intake. It looks like a reed valve in the drawing online, but that isn't anything to put any money on. I didn't know Mike Acre's site listed all of those details, I'll have to look at it closer.
 

SEAM

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Aug 12, 2013
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1,489
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Japan
Yupp, it is a reed valve engine. The reed valve is integrated into the insulator and thus not listed in the IPL.
With the carb removed the valve's condition (deterioration, stuck foreign object) can be checked easily.
 
p61 western

p61 western

ArboristSite Guru
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Jun 2, 2016
Messages
960
Location
northern California
It could be a pulse problem to,maybe partially blocked.My p-41 spit fuel out the front of the carb,the pulse hole in the reed was partially blocked.Got it clear and it ran great.
 
Andyshine77

Andyshine77

Tree Freak
Joined
Jan 25, 2004
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10,841
Location
Cincinnati, OH
The old reed valve engines seem to always have more spit back than piston ported engines. If the saw runs good and doesn't rattle, it's most likely fine.

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