Author Topic: Compression problems  (Read 68 times)

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Offline shoesnsocks

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Compression problems
« on: February 21, 2017, 03:01:36 pm »
Not sure if this is the right place to post this question. I'm a total noob mechanic without someone to train me. I'm working on a hand held blower right now that has a compression of 85  and the minimum in the book says 90. The customer used too much oil in there fuel, but the cylinder doesn't look that crazy bad ( a little varnish but the piston is clean on the sides I can see.) Someone already told me it might have a stuck ring on it but they can't see it to be sure (Tech service on the phone). Basically I'm not so sure the customer even wants to spend too much and he already needs a new carb, spark plug, and fuel tank grommet. How poorly will it run if the compression is 5 lbs below the book's minimum?

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Offline RoyM

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Re: Compression problems
« Reply #1 on: February 21, 2017, 03:11:35 pm »
What is the make and model? It sounds like it may be simply worn out, a new carb and plug may already make it uneconomical to fix.
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Offline shoesnsocks

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Re: Compression problems
« Reply #2 on: February 21, 2017, 03:35:56 pm »
It's an echo PB-250, It looks pretty new too, at least purchased within the last 5 years. the thing that gets me is the cylinder looks pretty clean except for the varnish around the bottom rim, no scoring or anything.

Offline Cut4fun .

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Re: Compression problems
« Reply #3 on: February 21, 2017, 03:48:22 pm »
I had one that had a stuck ring. I unstuck the ring and still running.  Clean the ring groove etc.  IMO 120psi min, below that they are iffy
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Offline shoesnsocks

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Re: Compression problems
« Reply #4 on: February 21, 2017, 03:58:32 pm »
I had one that had a stuck ring. I unstuck the ring and still running.  Clean the ring groove etc.  IMO 120psi min, below that they are iffy

Is it easy to put the cylinder and piston back together? I haven't done it before and my boss would not be to happy with me if it was something I couldn't put back together. We do have a kid that could do it but he won't be here till friday

Offline shoesnsocks

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Re: Compression problems
« Reply #5 on: February 21, 2017, 04:26:59 pm »
I actually got some info about it in the service manual. Is it necessary to get a new cylinder gasket?

Offline Cut4fun .

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Re: Compression problems
« Reply #6 on: February 21, 2017, 06:11:52 pm »
I reuse base gasket if in good shape. Be careful not to tear it on removal.
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Offline shoesnsocks

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Re: Compression problems
« Reply #7 on: February 21, 2017, 10:27:37 pm »
I reuse base gasket if in good shape. Be careful not to tear it on removal.

Right on thanks man. I'm going to talk to the boss about it all tomorrow.

Offline Al Smith

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Re: Compression problems
« Reply #8 on: February 22, 2017, 04:07:08 pm »
More times than not if you just squirt some WD-40. kroil or something in the cylinder and let it soak a couple  days it will free a stuck ring .

Offline RoyM

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Re: Compression problems
« Reply #9 on: February 22, 2017, 10:41:26 pm »
That is a good blower, I would go deeper. As was suggested, a stuck ring may be the problem. Check the air intake. Is the carb throat reasonably clean? If it is gritty air filter maintenance or lack thereof may be an issue.
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