First day running my Rocan Q with 30.5. Proper break in on a few tanks of gas. Switched to Stihl Synthetic oil 25:1, ripped on it for 5-6 minutes- motor acted like it ran out of fuel. Would not start back. Would not hit starting fluid or gas put in cylinder. Has good spark. Tore down to inspect cylinder. Any ideas?
Rovan Q 30.5 Cylinder
- Thread starter toddhall
- Start date
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Is the cylinder skirt missing on the top? Looks like it from my angle
- Thread starter
- #3
It is on there just a bad pic. Do you think the cylinder wall looks damage in the bottom of the pic? Think that would drop compression on a brand new engine? I didn't want to battle coronavirus to get a new compression guage.....
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- 19,475
Look a bit like piston slap to me. Although piston slap won't cause immediate issues. Im not an expert so take it with a grain of salt, there a few other guys who know alot more than me
@Top Dead Center
@Seandonato73
Welcome to the forum btw.
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- 2,044
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- Long Island, New York
Welcome to the forum?
Did you check fuel line,was bowl filling with gas.
Flooded?,did you let it just sit for awhile then retry.
Check for vapor lock?.
Check breather hole in tank.
Make sure pulse hole clear.
Reset the needles to stock.
A guy just the other day had a similar issue(I think) turned out his jets were not set to factory specs.
Usually teardown is last resort.
Was something else happening?.
Did you check fuel line,was bowl filling with gas.
Flooded?,did you let it just sit for awhile then retry.
Check for vapor lock?.
Check breather hole in tank.
Make sure pulse hole clear.
Reset the needles to stock.
A guy just the other day had a similar issue(I think) turned out his jets were not set to factory specs.
Usually teardown is last resort.
Was something else happening?.
- Thread starter
- #6
I checked all except for resetting the needles. I thought it lost compression the way it was running great and shut off, and it felt different on the pull cord so I tore into it. When I put it back together do I have to get a new head gasket or reuse that one? I did not try another spark plug (stupid I know ) but all spark looked good.
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- 2,044
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- Long Island, New York
I'd say yes,just in case.
It might be fine but might as well eliminate the possibility of it not.?
It might be fine but might as well eliminate the possibility of it not.?
Top Dead Center
Does party tricks ?
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- Colorado
Is the piston ring stuck in the ring groove on the exhaust side of the piston?
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Looks like the cylinder wall is all chewed up. Perhaps its just a poor photo but looks like a nasty gouge to me.
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- 2,390
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- Rochester,NY
So what does the exhaust side of the piston look like. The head looks scored .
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- 13,105
Did you check compression before you ripped it apart?
When you say it felt different pulling it over, what do you mean? Harder to pull easier to pull?
To me it looks like a lean run condition
Check the ring as advised if ok check the crank spins nice toss it back together and check for carb and fuel issues.
When you say it felt different pulling it over, what do you mean? Harder to pull easier to pull?
To me it looks like a lean run condition
Check the ring as advised if ok check the crank spins nice toss it back together and check for carb and fuel issues.
Stewart esham
Member
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Please don’t use that oil again our chain saws burn up on that stuff all the time use at least klots
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- 13,105
Why did you quote me? I didnt say anything about oil...
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- 2,044
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- Long Island, New York
Ha ha ha and the setup has begun...?
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- 13,105
Talk about digging up dead threads ?
And if we want to get into another oil debate I'm game, specifically if were going to talk about stihl hp ultra. If your saws are burning up on it you ain't doing something right.
And if we want to get into another oil debate I'm game, specifically if were going to talk about stihl hp ultra. If your saws are burning up on it you ain't doing something right.