550xp exhaust port

[Adamski]

Guys,

Anyone familiar with the exhaust port of a 550xp?

Is this normal or has someone been grinding on this cylinder in the corner?

And the piston looks beat on the top edge???

 

[Chainsaw Jim]

I'd be more concerned about those threads on the flywheel side. It looks like a power tool spun a Stratton mark on the edge of the hole and made its own set of threads on the way in.
Run it until it gets tired and buy a new oem top end. An oem piston/cylinder kit is currently listed on parts tree for $136.

 

[Adamski]

I'd be more concerned about those threads on the flywheel side. It looks like a power tool spun a Stratton mark on the edge of the hole and made its own set of threads on the way in.
Run it until it gets tired and buy a new oem top end. An oem piston/cylinder kit is currently listed on parts tree for $136.

Weirdly they threaded in and out smoothly. But on a side note I bought this as a non runner although the actual saw is very clean. Haven’t got round to tearing it apart yet. It has a good spark, it seems to have compression but I think it is low as there is not much difference between decomp and non decomp. Looking at it further since my first message it looks like someone has used a crap piston stop method as the cylinder squish band is scored dented from a screwdriver or something.. Time to pop it all off. Any other known issues with these 550’s?

Cheers for the advice [emoji3]

 

[Adamski]

This is why I want to save it. It is peachy..

 

[smokey7]

Wtf thats a weird looking port for sure.
Afaik early ones had some carb trouble 2012 ish saws those also had heat soak issues for hot restarts. Also ive heard of some p&c clearance issues that was updated. Oh also some speak of transfer o ring issues also. Send @Mastermind or @Tor R a pm they know a whole lot more about them ive never owned one and am only regurgitating what ive read and heard guys talk about.

 

[Ronaldo]

Transfer cover o- rings are definitely a known issue area and worth a look.

Sent from my SM-S320VL using Tapatalk

 

[Adamski]

Transfer cover o- rings are definitely a known issue area and worth a look.

Sent from my SM-S320VL using Tapatalk

Would that cause a non start, or just a lean situation that the auto-tune would correct?

 

[Ronaldo]

If remembering right the A/T will correct.......to a point. Depends on how much air is getting by. Nice looking saw, they are great runners, light and nimble.

 

[Adamski]

If remembering right the A/T will correct.......to a point. Depends on how much air is getting by. Nice looking saw, they are great runners, light and nimble.

It was $180 in your money (not UK £) posted. I am just hoping the cylinder is OK and it is carbon build pulling away etc that I can see when I look down the port.

They feel slimmer skinnier and more ergo friendly than the 346xp's and a helluva lot nicer sized and feeling than the ms261's

Quids in if it is a cheapish fix

 

[Moparmyway]

That exhaust port is fine .......... so is the piston.
At worst, a helicoil or timesert will fix the threads, but if it threads in there fine, and holds tight ................. run it and pretend that you stole it

Red Armor will alleviate all concerns about the flakes

 

[Adamski]

That exhaust port is fine .......... so is the piston.
At worst, a helicoil or timesert will fix the threads, but if it threads in there fine, and holds tight ................. run it and pretend that you stole it

Red Armor will alleviate all concerns about the flakes

SO if this is the case and as I don't have the saw with me at work what next to try and get this started. Just thinking off the top of my head.

Purge bulbs and lines all appeared OK. No obvious signs of issues any where else on my 3 minute observation.. With the decomp pushed in there is still resistance, more than say ANY other saw that I have used with a decomp. My 2065 with the decomp in is smooth as butter to pull over, this 550 is definitely not. With the decomp not pressed it is a little bit harder to pull over. I still think there is something wrong inside the cylinder as I swear I could see shiny scores at the intake side of the squish band as if someone had used something other than rope as a piston stop...

I will pull it apart tonight.

 

[Moparmyway]

I will pull it apart tonight.

Never hurts to do this.
Decomps ................ I cant stand them, they cause more agg than ease, especially when troubleshooting. Plug it for the time being to eliminate it as a variable. If it starts on a squirt with the decomp plugged, then, you've narrowed down your problems

 

[Adamski]

Never hurts to do this.
Decomps ................ I cant stand them, they cause more agg than ease, especially when troubleshooting. Plug it for the time being to eliminate it as a variable. If it starts on a squirt then, you've narrowed down your problems

I threw a tea spoon down the filter throat when I got it. Nothing.

 

[Moparmyway]

Plug the decomp and repeat

 

[Adamski]

Plug the decomp and repeat

Will do this evening. I also checked that I am not being a dummy with the single master control lever etc.. hahaha.

 

[cus_deluxe]

I just fixed a broken carb choke shaft on one of these for a friend, they couldnt get the saw to run at all. It was pretty noticeable on the feeling of the control lever, it felt like there wasnt enough resistance. Somethin to check anyway

 

[Adamski]

I just fixed a broken carb choke shaft on one of these for a friend, they couldnt get the saw to run at all. It was pretty noticeable on the feeling of the control lever, it felt like there wasnt enough resistance. Somethin to check anyway

What do you mean by broken choke lever. I have had the carb off and everything seems ok regards the carb. Do you mean between the choke lever and the master control lever?

 

[Mastermind]

Does it have spark?

 

[cus_deluxe]

Yep, if youve had it off and all is good then it should be fine. The nub on the end of the choke shaft that fits in the “v” of the master control lever was broken off. #12 is pointed right to the end that was broken off

 

[Adamski]

Does it have spark?

It has a good blue spark. 2016 model year. Just popped back at lunch to do some more diagnosis. Decomp works as it should. Intake side of piston skirt looks clean and fresh too.