balaban9331
ArboristSite Operative
i am putting together my stihl 090.the four screws that hold the cylinder to the crankcase,should i add locknuts to make it hold better?thanks,robert
cylinder question
- Thread starter balaban9331
- Start date
Help Support Arborist Forum:
lawnmaniac883
ArboristSite Member
Loctite red should do. Cheers
balaban9331
ArboristSite Operative
maniac,interestingly enough i was told not to use loctite.i have used it a thousand times but never for anything of this nature.thanks for the input.
Lawn Masters
Addicted to ArboristSite
the Stihl screws should be fine on their own. they've got a design built into the bottom of the head that should act as a locking washer on its own when properly tightened down.
balaban9331
ArboristSite Operative
lawnmaster,i got regular socket head cap screws(6mm from work),now i'm starting to worry.
How do you plan on tightening them? I dont think you can get a socket down through the holes on the jug. An Allen head or Torx head is what you will need.
sawinredneck
Addicted to ArboristSite
CaseyForrest said:
Snap-on and Mac both make long allen and torx bits that will work, if you are willing to pony up the cash!!
Andy
Lakeside53
Stihl Wrenching
use nothing on the threads... The design has worked for about 40 years so why mess with it now!
NWCS
Addicted to ArboristSite
on the 070 hotsaw i just put together tonight, i am using the cylinder bolts from an 066 purely for the T27 head. i would consider this the best option for ease and resistance to stripping the head out like the allen heads love to do.
cord arrow
Addicted to ArboristSite
Lakeside53 said:
uh-huh. if anything, use anti-seize.
it's about the proper application of torque applied to an engineering standard.
they DO NOT need your "help".
you care to re-engineer fasteners, i'll sic simon on ya.............
would you ever even consider lock-tighting, say, a cylinder head on your truck?
thought not.....................
RaisedByWolves
Addicted to ArboristSite
Its actually good advise if he dosent have the stock fasteners.
Loctite red was origonally developed to secure head studs (head bolts but with threads on both ends) on Hi po race engines. Thats why the comapny calls it "Stud Lock".
Loctite red was origonally developed to secure head studs (head bolts but with threads on both ends) on Hi po race engines. Thats why the comapny calls it "Stud Lock".
Lakeside53
Stihl Wrenching
I'd say - just get the reight fastners, but I believe he has them... and in any case these are just M6x25 hex socket bolts, not big race engine studs, and on studs its to stop the stud from being unwound by a stuck nut.
One problem with loctite on the cylinder bolts is that you cannot re-torque them, which you normally do after a few hours of running.
And, think about the next guy (may be you): 262 requires heat (350F, I think) to break the bond. It's hard to get the heat down the bolt without overheating the case, and how many guys even use heat, or, even recognize that the bolts have been loctited? Most just keep applying torque until something gives. I have to work on saws that have had liberal application of 262 and 271/272... sometimes the loctite gives and sometimes the magnesium casing gives. If I see the loctite, or suspect it, I hit it with a Ungar precision heat gun.
My 2c; its almost never required on Stihl saws except where indicated by Stihl. In each of Stihl's service manuals the fastener specs show torque and whether any specific product is required on the threads, and if so which product. Coils bolts are often secured in the crankcase by 242/243 as the laminations have some "give". Some mufflers (only a few) use 262/271 into the cylinder and 242/243 in the crankcase. None of the cylinder bolts use any product - just the correct torque.
One problem with loctite on the cylinder bolts is that you cannot re-torque them, which you normally do after a few hours of running.
And, think about the next guy (may be you): 262 requires heat (350F, I think) to break the bond. It's hard to get the heat down the bolt without overheating the case, and how many guys even use heat, or, even recognize that the bolts have been loctited? Most just keep applying torque until something gives. I have to work on saws that have had liberal application of 262 and 271/272... sometimes the loctite gives and sometimes the magnesium casing gives. If I see the loctite, or suspect it, I hit it with a Ungar precision heat gun.
My 2c; its almost never required on Stihl saws except where indicated by Stihl. In each of Stihl's service manuals the fastener specs show torque and whether any specific product is required on the threads, and if so which product. Coils bolts are often secured in the crankcase by 242/243 as the laminations have some "give". Some mufflers (only a few) use 262/271 into the cylinder and 242/243 in the crankcase. None of the cylinder bolts use any product - just the correct torque.
carvinmark
Addicted to ArboristSite
Interesting-I just rebuilt my 066.When I tore it apart I found one broken cylinder bolt and one laying near the base of the cylinder.I picked the saw up used and ran it for about 60 hours,then I heard a noise and immediately shut it down.It acted like it was seizing. I got lucky as there wasn't any damage and the bolt came right out.I wonder if the bolts need to be re-tightened?
Lakeside53
Stihl Wrenching
carvinmark said:
Usually only once after the gasket or whatever has settled a little. The newer style steel gasket really doesn't settle at all. Broken cylinder bolts are rare in Stihls as they are a very high grade and incredibly strong for their size. Most likely they were over-torqued, one broke and then the cylinder vibration took out the other.
It's really easy to over torque a 5mm or 6mm bolt. I can take them to torque (8-12nm) with a standard stihl T wrench, and that has only a 2 inch offset from center. With an 8 inch socket wrench on a T27, almost no effort is required at all. An inch/lb (or NM) torque wrench should be used... particularly if you don't have a feel for the correct torque.
SmithEC
ArboristSite Member
sawinredneck said:
Or even Wiha.
I seriously thought Wiha was a Chinese word until I went looking for what I think is possibly the required tool. I guess it's German. German tool for a German saw, right?
I'm thinking that I saw Wiha T-handles at Bailey's. I would think that if they carried these sockets, surely they could sell quite a few.
This a 6-inch T-27 in a 260. It easily reaches all the way into a 460, also.
http://img.villagephotos.com/p/2005-11/1105978/156(Small).JPG
This is what we're talking about, right?
sawinredneck
Addicted to ArboristSite
I haven't a bad word to say about Whia!!! I was using thier tools in Machine Shops for years, GOOD TOOLS!!!! I was unaware, however, that they made those sockets, thanks for the info!!
Andy
Andy
SmithEC said:Or even Wiha.
I seriously thought Wiha was a Chinese word until I went looking for what I think is possibly the required tool. I guess it's German. German tool for a German saw, right?
I'm thinking that I saw Wiha T-handles at Bailey's. I would think that if they carried these sockets, surely they could sell quite a few.
This a 6-inch T-27 in a 260. It easily reaches all the way into a 460, also.
http://img.villagephotos.com/p/2005-11/1105978/156(Small).JPG
This is what we're talking about, right?
That looks like a good way to strip bolts.
There is a reason Stihl sells T handle and L handle wrenches.
SmithEC
ArboristSite Member
I found this illustration in one of my service manuals. I suppose it does have an L shape to it. Is this the L handle one you're talking about?
http://img.villagephotos.com/p/2005-11/1105978/006(Small).JPG
http://img.villagephotos.com/p/2005-11/1105978/006(Small).JPG
SmithEC said:I found this illustration in one of my service manuals. I suppose it does have an L shape to it. Is this the L handle one you're talking about?
http://img.villagephotos.com/p/2005-11/1105978/006(Small).JPG
