Fuel line too soft?

[Mike Ray]

Working on Stihl 041 cranks no problem, idles, revs good, but when you put in wood after about two or three cuts starts bogging down and will die. I cleaned the carb and replaced impulse line same deal. Looking at fuel line it seems soft( part that is in tank) I can squeeze it together easily and when I lift it out of tank with a wire filter hangs straight down. I know it needs to be somewhat soft but this seems almost soft enough to be sucked together. What are your thoughts.

 

[alexcagle]

That sounds like your pickup hose is sucking shut before the tank vent lets "in" air. IMO

 

[lone wolf]

Working on Stihl 041 cranks no problem, idles, revs good, but when you put in wood after about two or three cuts starts bogging down and will die. I cleaned the carb and replaced impulse line same deal. Looking at fuel line it seems soft( part that is in tank) I can squeeze it together easily and when I lift it out of tank with a wire filter hangs straight down. I know it needs to be somewhat soft but this seems almost soft enough to be sucked together. What are your thoughts.

So replace it.

 

[Chevboy0167]

Does it feel a bit "gooey" between the fingers? Also may be a fuel tank vent problem...

 

[Mike Ray]

Yes I had decided to replace it, the vent is in the cap, have the crud and can't take a breath for coughing so it's on back burner for now, thanks for the replies.

 

[Mike Ray]

not looking at it but if I remember right there is an orange piece of rubber in top of gas cap is this the vent ? trying to find a schematic but no luck so far.

 

[Chevboy0167]

This???



https://www.ebay.com/itm/3853255501...plSpH8JzrY9QxNdD0XH2xvsAqa|tkp:Bk9SR67tot61YQ

 

[pioneerguy600]

The 041`s have a grub screw in the fuel cap, there is also an insert, kind of like a sleeve the grub screw is located in.

 

[Mike Ray]

that's what it looks like, I'm going to replace fuel line first then I'll ck the vent, as always thanks for the information you generously share , hope you all have a great day.I'm drunk from cold medicine.

 

[stihltech]

I used to blow the cap off good and try sucking on the bottom side with my mouth. Tells you right away if it is plugged.
Probably explains a lot about me also.

Soft hose a problem. also the elbow that fits in the hose at the tank outlet. Seen then leak pressure and vacuum at all those points. A check it all or nothing situation.

 

[Mike Ray]

thanks for the info, have a great day

 

[Mike Ray]

checked the vent in the cap today can't blow or suck air through, looks like two slots to pop the cartridge out, any tricks to this?This may very well be my problem.

 

[stihltech]

checked the vent in the cap today can't blow or suck air through, looks like two slots to pop the cartridge out, any tricks to this?This may very well be my problem.

Yes, pry the white piece out of the cap. There is a grub screw (set screw) in the top of the piece. Remove it. You will find it plugged with sawdust or rust. Clean it up really well. Install the screw in the white piece and check it in the same way before install. Also check the hole in the black cap. It must be open also.
IF the white piece is broken and the top part stays in the cap, it must be removed. Depending on how much is left in the cap, a small screw in a small drilled hole may get it out.

 

[Mike Ray]

Thanks so much , wanted to be sure how it came out, didn't want to break something, again thanks again for taking the time to help me.

 

[Mike Ray]

Took cartridge out of cap no grub screw, cartridge has 3 holes in bottom covered with thin orange piece of rubber held in place with a stem that goes thru the center,cap has a hole in top center,in the hole is a tiny Carter key ,I don't think it is supposed to be there,and I dug a lot of stuff out of this hole and still can,t blow air trying to Post and can't find away on my phone

 

[Mike Ray]

Here are pictures. question should anything be in the hole in the cap, where carter key is?

 

[stihltech]

A later style. Should pass vacuum if sucked on bottom. None if sucked on top. Will pass pressure if blown through from top.
To those thinking this sounds crude, it is the quickest way to check this style cap without a vacuum/pressure setup. Cleaning is always a great place to start.

 

[Okie]

You might also look at post #36 on pg 2 video at this link about testing (confirming it vents properly) Stihl chainsaw fuel tank vent testing.

Speaking of grub screw vents on chainsaws. The grub screw is not supposed to be screwed into the vent tube. Just push it in. If screwed in the threads will usually cut into the tubing and not vent. I've also confirmed this by doing vacuum tests of such.

https://www.arboristsite.com/threads/029-woes.365259/page-2

 

[Mike Ray]

is it supposed to have the carter key in the top, or is it there because someone had a "good idea". thanks

 

[Mike Ray]

OKIE thanks for thelink his description is exacly the way this saw acts, may leave carter key out when I clean it. top part is plugged can't blow through.