OK Stihl GURU's

Arborist Forum

Help Support Arborist Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

cuttinscott

Addicted to ArboristSite
Joined
Mar 14, 2003
Messages
3,068
Reaction score
636
Location
Greenwich, NY
Arborist dropped off a 200T no run.. pulled it down tonight 90 lbs compression, took apart when removing carb the low speed needle fell out of the case, took cyl off no major scoring some dirty air wear is all. But what concerns me is some dig marks on the right side of the crank pics to follow.. Has this saw ingested foreign matter or a bearing failure?? or is this Stihl's norm??


Scott
 
Crank or bearing failures on a 20T or 200T are extremely rare... Show us the piston pic as well.

90lb is way too low to even run, even at 130 they start and run like dogs, so I'm guessing it died in the last "run".
 
Last edited:
attachment.php


attachment.php


attachment.php
 
That more rearward mark in the top picture definitely looks like some kind of strike. Were both of the manifold nuts still on when you tore the saw down? Like Andy said bearing failures in these models are rare.
 
both carb nuts were on and tight the only thing loose was the low speed needle from the zama carb but not ingested..

Scott
 
Definitely ate something.

Why the low compression? Piston doesn't look all that bad. What is the ring gap in the bore?
 
The bottom of the intake side is worn smooth, makes me think the air filter was run dirty quite a bit and the piston may have started rocking in the bore. Are all the roller bearings present in the mains?
 
that will require more tear down I will check to see what my cust. wants to do before I dig deeper.

Scott
 
Rookie here....If those marks in the crank happened while running in the saw,
it looks to me it would have really damaged the case or piston,
the crank is so much harder than case and piston.......would there not
be some damage to something else in the crankcase to make those
marks on the crank?
 
I see serrated marks directly across from the "gouges". Could all these be from a holding fixture that was used to position the crank for a machining operation at the factory? Fixtures are always harder material so they don't wear. Possibly markings from the fixture jaws and rest pads/clamps?
 
Rookie here....If those marks in the crank happened while running in the saw,
it looks to me it would have really damaged the case or piston,
the crank is so much harder than case and piston.......would there not
be some damage to something else in the crankcase to make those
marks on the crank?

Gary's right-on. If something struck the crank to make marks that deep it would have exploded everything else in the crankcase. The crank is the hardest thing in there. I'd say they are marks left over from machining and wouldn't worry about them.

Jim
 
At this point I'd have to agree. The rest of the inside of the saw is too clean. I have however seen cranks do all manner of things- including breaking clean in half but the rest of the components would show extreme wear and tear by that time.

Almost all of the machine marks are gone from the intake side of the skirt so I'd say it's definitely time for a new piston and rings.
 
Maybe the saw has been "fixed" before, and the marks on the crank are from an old injury..

None of this explains the 90lbs though... but didn't we have problems with Cuttings gauges reading low before??:)
 
Maybe the saw has been "fixed" before, and the marks on the crank are from an old injury..

None of this explains the 90lbs though... but didn't we have problems with Cuttings gauges reading low before??:)

Well if you dont like my Gauge tell Snap-On its only about 6 months old and their small engine kit... Has little resistance on the pull it wont run either. Dirty Air cleaner YES but Ive never seen a 200T come in with a clean air cleaner MAYBE they need a better ail filtration system... Why did the low speed needle come out of the Zama carb? This saw is on its orig bar and is one of 3 in a tree service fleet. NO ITS NEVER BEEN INTO BEFORE unless the stihl dealer had it open before sale. I ASKED if anyone has seen marks in a stihl crank like these I GUESS I HAVE NO for a answer. Im sure this saw will end up in a junk pile along with 3 of his older 020T's. The only work done to this saw was the removal of the spark arrestor.

This is why I have little respect for stihl cause everyone thinks they do no wrong!!!! I am proud to sell and service DOLMAR saws since 1979..
As I have mentioned before as well The Local Stihl guy is more interested in selling pet food than fixing Stihl's

Scott
 
As I have mentioned before as well The Local Stihl guy is more interested in selling pet food than fixing Stihl's

Scott

Scott, that's why I think the right answer to the 'What saw should I buy' question is always 'What dealer do you like, and what kind of saws does he sell'. If I lived near you, I might run Dolmar's myself.

Of course, I live near a great Stihl dealer, so I get to run the best saws. :D :D :D

:notrolls2:
 
Maybe a drunken stihl engine assembler dropped the crank on the floor? no idea..

If the crank/bearings are o.k. I'd just drop in a new piston/rings and run it for another 2000 hours.

Sure, the air filters are whimpy, but the saws sure seem to last. Most of the dirt gets inside the filter when the filter gets completely blocked - then it pulls in around the edges. I have a few guys that now keep their filters clean and there is far less dirt in the wrong places. The older the saw gets the more it spits back. Most of the black sponges are missing. Once it really spits all over the filter the fine dirt togther with the oil matts the filters really bad. I do like the MS200 style - completely enclosed filter.

As for the Zama L screw.. no idea.. never seen that. Maybe there's a bad vibration from something wrong? The Zama L screw has a tight thread class and no spring, and I don't like that approach, but never have seen it give problems. I'd put locite 222 (or so..) on the outer threads of the neede if it's not tight.


And I wasn't trying to rev you up about your pressure tester (we've been around the block on this before), but 90 seems very odd for a saw with a piston etc like that. The reason it came in was probably the carb screw, but it was likely running poorly just prior to that... and it sure won't run at 90. At 130 they feel very limp in the pull.
 
Last edited:
Back
Top