MS 271 Head Question, Transfer cover came off

[BING38RT]

Hello,
I'm working on my uncles Stihl MS 271 and when I got it all torn down I found the the transfer cover had come off the head.

Now my question is can I reattach this some how or do I need a whole new head for it ?? I have never seen this happen so I figured I'd ask you guys/gals who are much more knowledgeable than me.

The bore is perfect, no piston transfer or scratches or gouges so that why I was wondering if it can be fixed.

Thank you in advance
( I've only been building and repairing saws for 2 yrs now but I've been using them for 20+ years )

 

[Gord404]

It wont be the first time I have heard that happen, there was a tread on that at one time

 

[BING38RT]

It wont be the first time I have heard that happen, there was a tread on that at one time

Is there a chance I can fix it ? Maybe with some Yammabond or JB weld or am I better off just buying a new head ?

I figured out what happened my uncle must have been cutting with a dull chain and of course he never cleaned any of the sawdust and oil gunk out so it probably overheated cuz I could see some white discoloration down near the transfers or maybe that was from an air leak. But it definitely look like it overheated at some point.

 

[Gord404]

I find it strange how they would glue that cover on and not use screws and seal like most other saws- cheaper and faster to get them sold I guess, sorry but have no respect for engineering like that- imo

 

[ZeroJunk]

There is an extreme heat JB Weld. Nothing to lose trying it.

May be other candidates that are better as well.

 

[SteveSr]

I find it strange how they would glue that cover on and not use screws and seal like most other saws- cheaper and faster to get them sold I guess, sorry but have no respect for engineering like that- imo

Actually, this is a new safety feature that is now built into most of Stihl's consumer / homeowner saws. It basically removes the saw (and takes away their ability to hurt themselves or their neighbors) from operators that are too dumb to know how to maintain or properly operate a chainsaw.

 

[Gord404]

Actually, this is a new safety feature that is now built into most of Stihl's consumer / homeowner saws. It basically removes the saw (and takes away their ability to hurt themselves or their neighbors) from operators that are too dumb to know how to maintain or properly operate a chainsaw.

Well now that makes sense

 

[ballisticdoughnut]

Actually, this is a new safety feature that is now built into most of Stihl's consumer / homeowner saws. It basically removes the saw (and takes away their ability to hurt themselves or their neighbors) from operators that are too dumb to know how to maintain or properly operate a chainsaw.

Shots fired!

 

[BING38RT]

Shots fired!

Like I said it's my uncle's

None of my equipment looks like caked in oil and saw dust. I clean my stuff

 

[Old2stroke]

Is there a chance I can fix it ? Maybe with some Yammabond or JB weld or am I better off just buying a new head ?

I figured out what happened my uncle must have been cutting with a dull chain and of course he never cleaned any of the sawdust and oil gunk out so it probably overheated cuz I could see some white discoloration down near the transfers or maybe that was from an air leak. But it definitely look like it overheated at some point.

There are epoxies that will do the job but you won't find them in any retail supply, they are specialized industrial items, very expensive and require special surface treatment on aluminum and a carefully controlled high temperature cure and post cure cycle. You would not be able to buy a small quantity either, so the only realistic way to get any is to have a contact in the AeroSpace industry that could "liberate" a sample. Unfortunately I've been retired so long I've lost any contacts I had, so can't be any help there.
p.s. I could be wrong about retail availability, they are now marketing RTV products that stand 650 deg, so maybe there is some "off the shelf" that will work.

 

[Chevboy0167]

https://www.jbweld.com/product/high-heat-syringe

 

[BING38RT]

There are epoxies that will do the job but you won't find them in any retail supply, they are specialized industrial items, very expensive and require special surface treatment on aluminum and a carefully controlled high temperature cure and post cure cycle. You would not be able to buy a small quantity either, so the only realistic way to get any is to have a contact in the AeroSpace industry that could "liberate" a sample. Unfortunately I've been retired so long I've lost any contacts I had, so can't be any help there.
p.s. I could be wrong about retail availability, they are now marketing RTV products that stand 650 deg, so maybe there is some "off the shelf" that will work.

Thank you for the reply.
I contacted Stihl and of course the "Equipment Specialist" couldn't give me an answer let alone know what a transfer cover was LOL

I ended up using some Dirko that's rated to 662°F and I tack welded the two locating tabs so we'll see if that holds or not. I figure if that's what they used to seal the head to the pan why not get it a try. Otherwise I'm just going to buy a crappy aftermarket head if it blows up or fails again.

I figured out why it failed in the first place. Upon further inspection they only applied the epoxy from the factory at two specific points and it never completely sealed. From my understanding they design them this way to protect it from blowing up but I personally think it's a tactic to get you to keep buying news saws.

Thanks again for getting me on the right track.

 

[BING38RT]

I find it strange how they would glue that cover on and not use screws and seal like most other saws- cheaper and faster to get them sold I guess, sorry but have no respect for engineering like that- imo

I thought it was just me that found that interesting. But I guess nobody would buy a new saw again if things lasted forever. But it's ironic how all the older equipment holds up better than these newer generations.

 

[Wizard]

Perhaps the center rib portion could be drilled and tapped for a single hold down screw, or stud.

 

[SteveSr]

Thank you for the reply.
I contacted Stihl and of course the "Equipment Specialist" couldn't give me an answer let alone know what a transfer cover was LOL

I ended up using some Dirko that's rated to 662°F and I tack welded the two locating tabs so we'll see if that holds or not. I figure if that's what they used to seal the head to the pan why not get it a try. Otherwise I'm just going to buy a crappy aftermarket head if it blows up or fails again.

I figured out why it failed in the first place. Upon further inspection they only applied the epoxy from the factory at two specific points and it never completely sealed. From my understanding they design them this way to protect it from blowing up but I personally think it's a tactic to get you to keep buying news saws.

Thanks again for getting me on the right track.

I have seen Stihl use Dirko under screw on transfer covers so If you tack welded both ends it should stay on. Dirko won't hold by itself obviously.

You are also extremely luck that this happened fast enough to kill the saw right away. Usually this causes a lean condition, more heat and ruined piston and cylinder (i.e. saw). BTW, I don't believe that AM parts are available for these saws.

 

[Gord404]

I did notice the have a few high heat JB- couple of different types- one is good for 1000 F and the other 550F- on absolutly clean surfaces it might work because its self bonding and strong and cheap on Amazon- just an Idea

 

[SteveSr]

I did notice the have a few high heat JB- couple of different types- one is good for 1000 F and the other 550F- on absolutly clean surfaces it might work because its self bonding and strong and cheap on Amazon- just an Idea

I think that Stihl probably uses some kind of industrial epoxy on their transfer covers. The issue with epoxys is that they get soft/weak as the temperature increases. Do a search on how to remove epoxy and you will see a lot of recommendations for heat guns!