Anyone ever cracked a piston using a piston stop??

[nmurph]

i have never damaged anything with an impact. as a matter of fact, i used it to remove the flywheel nut and clutch last night from a 290. i don't use a rope, just leave the plug in and give it a whirl.

 

[blsnelling]

Nope, never

BTW, were you using the screw in type?

 

[superduty5.4guy]

I feel better now that I know you have done it Brad, cause you definately know way more about saws than I do (or probably ever will), but yes I was using the screw in type with the rounded nub at the end. It didnt really blow a hole in mine because I stopped as soon as I felt the solid resistance go away but there was definately a gouge/dent and a couple small fractures leading to it. Doh!!

 

[thomas72]

I have had no problems using an impact unless the flywheel has an aluminum key. I always use rope.

 

[blsnelling]

I believe the screw in type is the wrong stop to use. You want to use the one that simply sticks in the plug hole and against the cylinder wall. That way the pressure is not concentrated in the center of the piston. That is what caused the failure of the piston shown above. If you and I had been using the right stop, the damage wouldn't have happened. Moral of the story...using a piston stop isn't a bad thing, but using the wrong one can be.

 

[blsnelling]

I always use rope.

Rope isn't always the right answer either. The bent rod below was caused by using rope. The rod was not at the ideal angle. Using the correct piston stop would have prevented this bent rod.

 

[GPETER]

Dont feel bad, it's only a mistake if you dont learn from it!

I did the same thing on my 064 except I sheared all of the aluminum threads out of the spark plug hole as well. I had to get a thread insert kit as well as a piston for the repair. The saw needed a piston anyway but still I should have known better.
In my shop I have good and bad days and others where I should just walk away and do something else!

It can all be repaired and a very minor error of life.

I have heard an that an impact can do damage to the crank and flywheel. I was warned by my friend that is a stihl tech, he said that he see's plenty of saws come in the shop that have the key sheared. The best way is to use rope or better yet the plastic shihl tool and a wrench.

 

[Dan_IN_MN]

Rope isn't always the right answer either. The bent rod below was caused by using rope. The rod was not at the ideal angle. Using the correct piston stop would have prevented this bent rod.

Brad

What saw was this out of? There doesn't look to be much "structure" in that rod for strength!

Looking at your post count, you're going to hit 20,000 post count real soon!


------------------------------------------------------------------------

I haven't had any trouble with using an impact on removing clutches and flywheels. One just needs to think things through. Haste makes waste! Infact, I used an impact on removing the engine mount bolts on an MS 290 that was giving me trouble with manual methouds. My little 3/8 butterfly impact works well!

OP..... are you going to replace the rings too?

Dan

 

[Fish]

I always use an impact or "impact action" with a punch, with nothing in the
combustion chamber, just the plug in place.
I also work on these for a living, and have not damaged anything yet.

However, using an impact, or any method, involves some use of common
sense and self control.

A long time ago, I was removing a manifold from my truck, and I listened to
a guy preaching against impact wrenches, so I used a big ratchet, and
broke the first bolt, then used an impact on the rest, and they came out without
a problem. Spent more time and money on the broken bolt than the rest of the job.....

Moral of the story, I am not sure...........
Don't believe just anyone, I guess.......

 

[Fish]

Brad, you brought it up, you ought post a link to the "infamous" thread....

 

[blsnelling]

Brad, you brought it up, you ought post a link to the "infamous" thread....

I think I'll pass

 

[2000ssm6]

I used rope for a long time, worked great but ya have to watch those ports. The center of the piston is the weakest area, I never liked piston stops that thread into the spark plug hole. I will be ordering a new stop from Stihl shortly that goes up against the outer edge of the piston. It is called a "locking strip" and is part # 0000 893 5903. This is the best method/tool I've seen so far.

 

[THALL10326]

I feel better now that I know you have done it Brad, cause you definately know way more about saws than I do (or probably ever will), but yes I was using the screw in type with the rounded nub at the end. It didnt really blow a hole in mine because I stopped as soon as I felt the solid resistance go away but there was definately a gouge/dent and a couple small fractures leading to it. Doh!!

Bingo, wrong piston stop. Any angled spark plug hole uses a plastic angle piston stop.

 

[THALL10326]

one word- IMPACT.

One impact, one busted clutch and one busted flywheel. Three words are better, right piston stop.

 

[superduty5.4guy]

Well, like i said, I learn something new every day. Next tool on my list... stihl piston stop. Thanks fellas, hopefully i will stop breaking stuff eventually (probably not though). I guess my first step in the right direction was throwing the threaded piston stop in the trash can. And again, thanks everybody for sharing your experiences with screwing up too, it makes me not feel so bad ha. I think I'm going to start a wall of shame in my garage with all of my screwups so all I have to do is glance at it and rethink something that I'm working on that is questionable.:monkey:

 

[THALL10326]

Rope isn't always the right answer either. The bent rod below was caused by using rope. The rod was not at the ideal angle. Using the correct piston stop would have prevented this bent rod.

I got the twin to that,LOL Those things are like a magnet to water too.

 

[blsnelling]

Bingo, wrong piston stop. Any angled spark plug hole uses a plastic angle piston stop.

Go get em ole Tom! You learned me...you can learn anyone, lol

 

[superduty5.4guy]

I'm assuming this is the correct part (link) http://cgi.ebay.com/New-Piston-Stop...emQQptZLH_DefaultDomain_0?hash=item53dfc61433

Question is, is this the right part and what is the correct way to use it?

 

[blsnelling]

I got the twin to that,LOL Those things are like a magnet to water too.

Yes you do And man is that crank ugly!

 

[buicken]

I use a impact for old saws, but its a cheap electric junky impact gun.
It doesn't have the power to remove the lug nuts on my car, but usually works good on saws. I figure its not strong enough to break anything. Sometimes to much power is not so good.