Chainsaw problem

[Bruce King]

21 yr old Husqavarna 51 has been sitting around most of the time for 6 years. The pull cord assembly is good but takes a tremendous amount of effort to pull it 6 inches. It’s not the safety arm or the clutch. With the plug removed it’s smooth and easy. Has about 1/64 buildup on top of the piston. Internet sources say it’s very common but no one ever claims to have ever truly fixed this particular problem. I think the engine needs to come apart for cleaning and inspection. Anyone fixed one like this, very high compression?

[Izzy Camire]

Bruce, I have a 51 which I use when needed. The first couple pulls on the cord are like you describe I can only get a few inches. I keep at it and a couple of pulls later it is ok and it starts right up. The compression on them gets your attention. You may want to keep pulling and get it to start and perhaps it will clear itself up.

[Doug Dawson]

Bruce, I have a 51 which I use when needed. The first couple pulls on the cord are like you describe I can only get a few inches. I keep at it and a couple of pulls later it is ok and it starts right up. The compression on them gets your attention. You may want to keep pulling and get it to start and perhaps it will clear itself up.

If you keep it just inside the front door, and test it periodically just like a smoke detector or a GFCI (test monthly), it pulls easier.

[Bruce Wrenn]

Don't they have a compression release? My 50+ year old Roper (Craftsman) has one. Could be compression release valve is stuck from lack of use.

[Bruce Wrenn]

If you keep it just inside the front door, and test it periodically just like a smoke detector (test monthly), it pulls easier.

Crank it inside and get two tests for the price of one, smoke detector and chainsaw. .

[Bruce King]

It used to get a little hard to pull but now the rope will break if I pull any harder. Saw a video on rebuilding a 55 which has a compression release but so far I don’t see one on the 51.

[Tom M King]

Ask in the Chainsaw forum, on the Forestryforum. Someone there will know about that specific saw.

[Bruce King]

Ask in the Chainsaw forum, on the Forestryforum. Someone there will know about that specific saw.

I was on there, that’s where I found this to be a common problem with many saws. Some fixes are on there but no help for mine. I’m taking the piston out this afternoon to look.

[Bruce Wrenn]

Could be a carbon build up, raising compression. PB Blaster makes a carbon desolving spray for small engines.

[Bruce King]

Plenty of carbon and something on the piston side. No scoring evident. After all this work I’ll be installing new parts. Having trouble with the ads though. Picture of whole top end kit with a part number of the cylinder is common. Mine is a 44mm and most kits are 45 or 46mm and they say they will work. Anyone upsized a cylinder on a chainsaw?

[Bruce Wrenn]

Parts list shows a decompression vavle

[Bruce King]

The 55 uses the same documentation as the 51 with notations on differences. 51 epa does not have one.

[Ronald Blue]

If I am reading your comments correctly your cylinder bore is 44 mm? Unless you are installing a matching piston you wouldn't want that sort of clearance. That would be a recipe for disaster. I'm probably misinterpreting what you are referencing.

I looked up the specs and it listed it having a 45 mm bore.

[lowell holmes]

https://www.lowes.com/search?searchT...80v%20chainsaw

Check this site, I have one and it is good.

[lowell holmes]

Check this site, I have one and it is good.

https://www.lowes.com/search?searchT...80v%20chainsaw