Stihl FS38 trimmer primer bulb sucking air in and runs badly

XGamer223

Active Member
Joined
Sep 13, 2016
Threads
14
Messages
62
  • / Stihl FS38 trimmer primer bulb sucking air in and runs badly
There is a limiter to prevent richening up the screws very much, so pulling them is what is next to be able to richen them further.View attachment 57455View attachment 57456
Hi and thanks for your answer.
But this isn't it, sadly.
I placed a 100% working carb from a different Stihl, and the trimmer works just fine, so that concludes that's a faulty carb, not the fuel lines, filters, and what not. Also note: the carb I placed it on still has the limiter caps on it.
Thanks anyways, and sorry for my late answer!
 

StarTech

Lawn Royalty
Top Poster Of Month
Joined
Feb 19, 2020
Threads
76
Messages
10,219
  • / Stihl FS38 trimmer primer bulb sucking air in and runs badly
C1Q-S97
 

Fish

Lawn Pro
Joined
Aug 2, 2013
Threads
11
Messages
5,130
  • / Stihl FS38 trimmer primer bulb sucking air in and runs badly
Was the throttle cable ends different?
 

StarTech

Lawn Royalty
Top Poster Of Month
Joined
Feb 19, 2020
Threads
76
Messages
10,219
  • / Stihl FS38 trimmer primer bulb sucking air in and runs badly
The FS 38, 45. and 46 use the same parts most times but are some differences noted in the IPL for the three.
 

Fish

Lawn Pro
Joined
Aug 2, 2013
Threads
11
Messages
5,130
  • / Stihl FS38 trimmer primer bulb sucking air in and runs badly
Yes, the units have had some minor changes, the throttle cable ends, and slight changes in the air filter assembly, handle, etc.., but the 4140 powerhead has been pretty consistant. The throttle cable end change has forced me to include the throttle cable with the carb on my listings.
Also it is the same powerhead as the fs55. I popped one on a fs55 rig and it is great.
 

Fish

Lawn Pro
Joined
Aug 2, 2013
Threads
11
Messages
5,130
  • / Stihl FS38 trimmer primer bulb sucking air in and runs badly
Here is the one I sell, the cable has the z-bend end.
38carb.jpg
 

XGamer223

Active Member
Joined
Sep 13, 2016
Threads
14
Messages
62
  • / Stihl FS38 trimmer primer bulb sucking air in and runs badly
Bump.
Anyone got any insights?
 

StarTech

Lawn Royalty
Top Poster Of Month
Joined
Feb 19, 2020
Threads
76
Messages
10,219
  • / Stihl FS38 trimmer primer bulb sucking air in and runs badly
You have already got it down to the carburetor as being the problem. Sometimes these carburetors are just beyond repair and has to be replaced. I had primer base to go bad and they cost a much as a complete carburetor.
 

XGamer223

Active Member
Joined
Sep 13, 2016
Threads
14
Messages
62
  • / Stihl FS38 trimmer primer bulb sucking air in and runs badly
You have already got it down to the carburetor as being the problem. Sometimes these carburetors are just beyond repair and has to be replaced. I had primer base to go bad and they cost a much as a complete carburetor.
So, no repair kit they sell online wouldn't help? Seems to me that it contains all the wearable parts.
But anyways, there's an obvious issue with the carb. Even though, at some trimmers I've seen online, the bulb acts the same as mine. Maybe the problem lies somewhere else, since it doesn't run good. I might give it a good clean again.
 
Top