MS-290 rebuild

[Woody912]

Uncle gave me one that had been straight gassed, quite obvious that getting to the cylinder is going to be much tougher than my 036's. Am I going to end up hating this? Is the 039 conversion worthwhile? Probably not enough difference in weight and power to make me want to add this one to the starting lineup.

 

[stevetheboatguy]

Definitely worth upgrading to the 49mm cylinder. It's not any more expensive and it's a night and day power difference.

Just my .02


Steven

 

[a. palmer jr.]

Not hard to remove engine but do it when you have some time to spare...ask any questions you want about the rebuild, many of us have done it before..I have two apart now..

 

[windthrown]

I would up it to a 310, as that has by far the best AV of the lot. I have had many of the 1127 series saws. The 310 and 390 have larger carbs than the 029 and the 290 though. So maybe sticking with the 290 would be easier. The clamshells can be more of a PITA to rebuild, compared to the pro saws. I would get (and have gotten) a whole OEM engine block to replace it and swap it in. Looks like there are several 290 complete used Mahle engines on Ebay for $75 or so. I would go that route, as I have on the 1127 and 1123 series saws. Mahle is way way better than anything Chicom. You have to pull the flywheel and clutch to pull the engine from these saws. Remember that the clutch is reverse threaded. And you need a small puller to get the flywheel off.

 

[HarleyT]

Best AV?

Bigger carbs?

 

[HarleyT]

The ms290,310,390 are pretty much the same saw, except for piston/cyl differences.
The 310-390 has a slightly larger jet in the carb, and of course a 3/8 sprocket.

 

[a. palmer jr.]

You don't need a puller to remove a 290 flywheel, just loosen the nut and strike the flywheel on the edge, preferrably not the edge with the magnets..

 

[windthrown]

Best AV?

Bigger carbs?

Bigger carb jets in a 310/390 carb. Yes.

Best AV, also yes. Very noticeable. I have owned and run them all, as well as the pesky 029 non-super. Here are the 1127 MS series AV numbers:

Vibration in m/s*s for: top handle, back handle
MS290: 4.6, 5.7
MS310: 4.3, 4.7
MS390: 5.9, 5.1

Big difference in AV

 

[windthrown]

The 029, 029 Super and MS290 here came with 3/8 std sprockets as well. I have never seen a stock 1127 saw with .325 in the PNW. None of mine had anything other than the 3/8 spur drive and 3/8 std B&C (I have had over a dozen of them). I swap them out with the 036 rim drive brake/clutch drums. The smaller pre-360 rim drive hub works fine and can be swapped in if one of the OP's 036 is upgraded with the later larger 360 clutch drum kit. The later 360 clutch drum is recommended on the 036 to keep them from grenading. The 036 rim drive is a good pro feature that you can swap into these saws to replace the spur sprockets.

 

[Woody912]

I would up it to a 310, as that has by far the best AV of the lot. I have had many of the 1127 series saws. The 310 and 390 have larger carbs than the 029 and the 290 though. So maybe sticking with the 290 would be easier. The clamshells can be more of a PITA to rebuild, compared to the pro saws. I would get (and have gotten) a whole OEM engine block to replace it and swap it in. Looks like there are several 290 complete used Mahle engines on Ebay for $75 or so. I would go that route, as I have on the 1127 and 1123 series saws. Mahle is way way better than anything Chicom. You have to pull the flywheel and clutch to pull the engine from these saws. Remember that the clutch is reverse threaded. And you need a small puller to get the flywheel off.

Can I get the cylinder off without going all the way into the crankcase? I do not have a casesplitter at this time although that may become my next project

 

[HarleyT]

Same AV mounts on all 3 models, same handles...

 

[HarleyT]

You don't need a puller to remove a 290 flywheel, just loosen the nut and strike the flywheel on the edge, preferrably not the edge with the magnets..

Hit the flywheel nut, hold the flywheel.

 

[HarleyT]

Just use a deep well socket and the flanged nut..

 

[a. palmer jr.]

Hit the flywheel nut, hold the flywheel.

Try it my way, much less damage and easier.

 

[HarleyT]

Damage?

 

[HarleyT]

Hitting the flywheel?

Where? With what?

 

[windthrown]

Can I get the cylinder off without going all the way into the crankcase? I do not have a casesplitter at this time although that may become my next project

No cases to split on these. No case splittter is needed. They have a plastic engine chassis that the metal clamshell engine is bolted to at the base. The clamshell engine comes apart with torx bolts. The engine is also mounted to the chassis with torx bolts.

 

[windthrown]

Same AV mounts on all 3 models, same handles...

WAY different vibration from the engines though. The AV differences are YUUUUGE (as The Donnald would say it). YUUUUGE!

 

[HarleyT]

So not really the best AV then, but better engine vibes?

 

[windthrown]

Try it my way, much less damage and easier.

I have broken fins on flywheels that way on 1123 saws. Pullers are easier.