stihl ms 261cm rebuild?????

[plotthound]

ive got a stihl 261cm project saw sitting on the bench.it would not run due to bad compression,so i pulled the cylinder off of it and found major scoring on the piston and cylinder.on closer inspection i found some metal chunks on the crankshaft and discovered that the connecting rod bearing had failed and a needle bearing came loose,thus causing all the damage.was wondering if any of you guys have taken one of these saws apart before to preform this repair?i watched a youtube video on it and it looks pretty tough and some specialty tools were used.any input would be greatly appreciated,thanks.

[bgsengine]

yeah, splitting the case may involve special tools often, like a crankshaft puller, clutch puller, flywheel puller, even crankcase splitter (cause the ball bearings are a press fit into crankcase) but the job can still sometimes get done without busting the crankcase or something.. there's some models of saw that have threaded holes on one side that are used with regular screws to "push" crankcase apart.. but most times just had to spend a few hours with a soft mallet, blocks of wood, propane torch, and dry fuel & oil tanks (or a fire extinguisher handy) so unless you want to invest in the tools needed (which Ive seen can cost as much as $250 for something you could build easily if you have a welder and some machinist skills) or the time (could take several patient hours moving things by thousandths of an inch at a time), you may find it a challenge not worth taking.. (not to mention the cost of new crank assembly and new jug kit which if you go OEM will cost you more than just buying a whole new saw)

[KE4AVB]

Listen to BGS as Stihl will require special tools per their service manual but things can be done otherwise if you are inventive enough. But as he said research the replacement parts cost first. The crank last time I brought was $150 US from Stihl but HL Suppy has an after market one for $91 but it is currently on sale for around $64.

1141 080 0400 Crankshaft Assembly

If you wish I can send you the service manual PDF via your registered email address. Just need the okay.

[plotthound]

thanks for the info guys,maybe through the xmas holidays i will try to get it apart just to see what kind of job it is.(better than watching tv) please go ahead and send me the service manual KE4AVB thanks.

[RoyM]

What kind of usage is it seeing? If the customer is a weekend warrior cutting for his own use an aftermarket crankshaft is probably adequate. If it is run daily OEM is the way to go but now it is a parts saw due to cost.

[plotthound]

thanks roym,looks like your right.this will be a parts saw.way too expensive to fix it

[SUKI]

Now you know why most time all we do is carburetor, fuel lines, clutch, and bar/chain replacement and no major repairs. Parts usually very high verses the rewards. I personally seldom even do piston/cylinder change out any more. Even when we do it is with cheaper after market parts.

[plotthound]

i have 3 saws from my work,2-261c's and 1 271.all 3 have internal damage.i might be able to save one 261c,i dont see anything wrong with it except one little scuff on the piston and a possible leaky crank seal.looks like it may have been left idleing with the brake on,the clutch bearing is completly melted and the clutch itself is blue from excessive heat.are any of you guys experts at pulling crank seals?

thanks

[bgsengine]

other than seal pullers, tricky part on some is just getting access to the seal in the first place, but if I don't have a puller, sometimes can fashion one from a self tapping screw, or carefully drive a flat screwdriver blade between crank and seal and pry out - but you must be very careful doing that so as to not gouge the aluminum crankcase that holds the seal.. some seals are mounted into a plate which is then bolted on (or some are mounted to the oiler pump) and those are a bit easier..

[bobodu]

Quad -yes, GOOD LARGE outboard- yes....chainsaw-no.