038 brake spring damages case

[irhunter]

The main chain brake spring is eating my case. The big hole in the brake flag "lever" (the steel thing which bolts to the plastic brake flag) was wallowed out and might have messed up the geometry. I have replaced the lever, but the spring still rides in those grooves it has cut in the case.

It is a Stihl 038M.

Thoughts?

Roy

 

[Mad Professor]

Is the spring bent?
Clean it up and fill the grooves with JB weld. You could put a sleeve of thin tubing around the spring as long as it don't interfere with the brake's function.

 

[irhunter]

Thanks.

Right...I had not thought about bent spring issues. But, I have nothing to compare mine to.

The saw came to me with a non-working brake. The new lever has seemingly fixed the brake-function problem. But not the spring-rides-up-in-grooves problem.

I will inquire about the availability of a new spring.

 

[Mad Professor]

Thanks.

Right...I had not thought about bent spring issues. But, I have nothing to compare mine to.

The saw came to me with a non-working brake. The new lever has seemingly fixed the brake-function problem. But not the spring-rides-up-in-grooves problem.

I will inquire about the availability of a new spring.

If the spring works I'd keep it. Take it off and see if it's bent. Simple bend it back.
You can cut a strip of plastic from a milk jug and wrap that around the spring to stop the rubbing. Make sure brake still functions.
Some stihls (036 for one) came with a section of hose, as I mentioned above, to cover the spring

See #7

 

[SteveSr]

Thanks.

Right...I had not thought about bent spring issues. But, I have nothing to compare mine to.

The saw came to me with a non-working brake. The new lever has seemingly fixed the brake-function problem. But not the spring-rides-up-in-grooves problem.

I will inquire about the availability of a new spring.

The spring is supposed to have a piece of rubber/vinyl hose around it to keep it from doing this. Check the IPL. Nevere seen a Stihl without a hose on the brake spring.

 

[Mad Professor]

The spring is supposed to have a piece of rubber/vinyl hose around it to keep it from doing this. Check the IPL. Nevere seen a Stihl without a hose on the brake spring.

That's a later Stihl addition. Earlier ones like 028 and 038 didn't have the hose. I've not tried putting one on my 038s or 028.

 

[irhunter]

My IPL for the 038 shows no plastic cover for the spring. But, my 036 doesn't have the plastic spring cover...and, I have been intending to buying one for it. I will buy an 036 sleeve and see if it fits the 038.

I will say, when I put the spring on the 038...it went on surprisingly easily. Not long ago, I did the spring on an 026 and its spring was under a lot more tension than the 038. I will pull the 038 spring and try re-bending...but, I bet I end up buying a new spring.

I will report back.

 

[SteveSr]

My IPL for the 038 shows no plastic cover for the spring. But, my 036 doesn't have the plastic spring cover...and, I have been intending to buying one for it. I will buy an 036 sleeve and see if it fits the 038.

I will say, when I put the spring on the 038...it went on surprisingly easily. Not long ago, I did the spring on an 026 and its spring was under a lot more tension than the 038. I will pull the 038 spring and try re-bending...but, I bet I end up buying a new spring.

I will report back.

Yea, too weak spring tension would also allow the spring to vibrate more. Also consider that Stihl may have found this issue in earlier models and added the hose covering in later models to prevent it.

 

[Bob Hedgecutter]

Probably time for a freshen up of all the wear items within the brake mechanism- keep everything fresh and tight and it will be less prone to jump about and wear things out that are not meant to be part of the equation.