Stihl 290 Piston

I acquired a Stihl 290 from someone who didn't take good care of this saw. It was explained to me that during usage the saw let out white smoke and "ceased" to run. The muffler was off when I received this saw and I could easily see that piston had damage on the exhaust side.

Just to get some feedback, does the cylinder look in okay condition to reuse? If so, I can feel some indentations and will most likely sand the cylinder down. What grit of sandpaper work best for this? The intake side of the cylinder looks great.



As you can tell on the piston the rings were stuck to the piston. I tried taking the rings off and ended up breaking it, doesn't look like the rings will come off easily.

I'd say the P&C are junk. Time for a 390 upgrade.

I'd say do a search on cleaning up cylinders, and see if that one might be re-useable. There is one line on the LH side in the pic that might be a groove. If it cleans up, you're only going to need a $35 piston to get it going again. Plan on a new fuel line in any case.

029,290 golf P&C off ebay under $100 USD ,Thats what my 310 got when i lean seized it ,on my 5th tank and no problems yet,worth a shot

B200Driver said:

I'd say do a search on cleaning up cylinders, and see if that one might be re-useable. There is one line on the LH side in the pic that might be a groove. If it cleans up, you're only going to need a $35 piston to get it going again. Plan on a new fuel line in any case.

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Good stuff there. The only real way to know is to clean it up and see what you get. But that does look pretty bad. There are some chunks out of your piston.. that doesn't generally bode well for the bore. Give a go, though! You might get lucky!

That looks pretty bad. But you won't know until you get some of the Al cleaned off.

blsnelling said:

That looks pretty bad. But you won't know until you get some of the Al cleaned off.

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I don't see that cleaning up. The piston has CHUNKS missing! But, I guess anything is worth trying once.

I still vote for 390 P&C.

Since the piston is missing parts of it what does that indicate? This is my first job with a damage piston and cylinder.

Does a 310 piston/cylinder combo work for a 290? I have found a used, but in great condition, Stihl 310 combo that I can acquire. I am leaning more towards replacing with a used original Stihl part than what I could get on Ebay.

EtzCutter said:

Does a 310 piston/cylinder combo work for a 290? I have found a used, but in great condition, Stihl 310 combo that I can acquire. I am leaning more towards replacing with a used original Stihl part than what I could get on Ebay.

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Pretty sure that bolts right on. AFAIK the 290/310/390 P&C all interchange.

any of those three engines will interchange with each other,

I found a 310 replace cylinder/piston. My next question, will the carb in a 290 work in a 310?

EtzCutter said:

I found a 310 replace cylinder/piston. My next question, will the carb in a 290 work in a 310?

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I'd say so, it's only a 4cc difference in displacement. May require a bit different tuning, but no biggie.

The 290/310/390 are all the same parts just different bore sizes.

The P&C look like they are toast. Does it look like the plating on the cylinder is scratched thru?

carb jetting is different on the 290 than on the 310/390.

Looks like it was really ingesting some wood chips by the look of them stuck all over the piston. Man I have seen straight gassed saws look better than that holy Crap!

nmurph said:

carb jetting is different on the 290 than on the 310/390.

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Really? Why would that be? I'll have to check the book tomorrow. Not doubting you, just curious.

bitzercreek1 said:

Really? Why would that be? I'll have to check the book tomorrow. Not doubting you, just curious.

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Larger displacement, needs more fuel, larger jets. I still think you could open up the high and low screws on the 290 carb to make it run with a 031/310 p&c.

I have an 039 that is in the exact condition (burned up piston and damaged cylinder). I will take a look at both carbs and find out how the now 310 will need to be adjusted for the change in displacement.

joecool85 said:

Larger displacement, needs more fuel, larger jets. I still think you could open up the high and low screws on the 290 carb to make it run with a 031/310 p&c.

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I know but its only 2.5ccs away from the 310 and 7.5 from the 390.