Gas spits out of carb on saw when running
- Thread starter Efisher26
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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.
I had a weedeater blower with the same symptoms, and a new piston fixed it.
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Might pull off the carb and peek at the reed valve.
All piston ported 2-strokes do this to some extent. However, it does worsen as the piston skirt becomes worn.
As long as it is running well I'd put the air filter back on and run it.
When I did that the filter just saturated after a while and wouldn't run...?
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Sounds like a bad case of reflux, try some Pepcid AC in the mix.
You certainly can't use that as a tuning guide. Tune it as required to run correctly.
If it's doing that when tuned correctly, you definitely have an issue that will require further inspection.
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.
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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.
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BTW, it looks like a pain to work on.......
Perhaps this is a reed valve engine. http://www.ebay.com/itm/ECHO-CS-280...621695?hash=item35ff3f8d3f:g:gt8AAOSweW5VUNd-
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It is a reed valve engine, looking at the IPL, the carb appears to feed straight into the crankcase suggesting a reed valve. This makes sense, as most Echos of this era where reed valve engines.
A pic the valve is here https://store.chainsawr.com/products/echo-cs-280-e-ep-chainsaw-reed-valve.
A pic the valve is here https://store.chainsawr.com/products/echo-cs-280-e-ep-chainsaw-reed-valve.
It sounds like a leaking reed valve to me. It might be just a bit of dirt under the reed. You can pull it apart and sand the reed block flat and then put it back together.
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.
With the carb removed the valve's condition (deterioration, stuck foreign object) can be checked easily.
p61 western
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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.
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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