Stihl HS 45 hedge trimmer

[vettman]

I can start the engine, but it won't accelerate to operating RPM. Trimmer is 4 years old but probably has less than 10 hrs. of use. The fuel filter is not clogged because I can blow back through the fuel line with no problem. I believe there's a small hole somewhere along the fuel line. The fuel bulb only sucks air and will not fill with gas. I plan to order a new line and filter. Now for the questions. Does Stihl's fuel line part no. 4228 358 0800 extend from the carb, into the tank and attach to the filter? Is it a single piece of molded line that seals at the tank with a molded in grommet? In the parts diagram for the trimmer, there's another straight piece of fuel line (the diagram states it is part of a kit) that enters the tank through a grommet. Is this the feed line for the bulb, or does the bulb fill from the line that feeds the carb? I could probably sort most of this out on my own if the parts diagrams were a bit larger/clearer.

Thanks for any and all follow-ups

 

[Fish]

Remove the air filter, ands that thingee screwed into the muffler, dump out the old fuel, and buy fresh, and try to start it again..

It is probably the muffler screen thingee fouled, like a potato in your tailpipe, and if so, clean or replace the air filter too!!!!!

But let us know...

 

[vettman]

Remove the air filter, ands that thingee screwed into the muffler, dump out the old fuel, and buy fresh, and try to start it again..

It is probably the muffler screen thingee fouled, like a potato in your tailpipe, and if so, clean or replace the air filter too!!!!!

But let us know...

The "thingee" is the spark arrrestor screeen and it's clean. Even if that were the issue, it would not account for the fuel bulb not filling up, right? The bulb is intact; it's not cracked and it exhausts air into the fuel tank when it's depressed.

Thanks for responding

 

[Fish]

It is not actually a "primer" bulb, but a purge, it pulls fresh fuel through the carb, and then dumps it back into the tank, so if it is doing as you describe, you likely have a clog in your carb, or the needle may just be stuck from sitting over the winter, so
remove the carb and disassemble and clean, remove the needle/spring/needle and hold up to a light, you should be able to see
light clearly through the orifice beneath the screen, so visually verify that it is totally clear, because is may be partially clogged,
letting a little fuel through, but not enough to accelerate.

If it looks like you need a new kit or any parts, ask the Stihl dealer the price of a new carb, as many of these models, they have dropped the price of a new carb just a few dollars above the price of a new kit.

 

[vettman]

It is not actually a "primer" bulb, but a purge, it pulls fresh fuel through the carb, and then dumps it back into the tank, so if it is doing as you describe, you likely have a clog in your carb, or the needle may just be stuck from sitting over the winter, so
remove the carb and disassemble and clean, remove the needle/spring/needle and hold up to a light, you should be able to see
light clearly through the orifice beneath the screen, so visually verify that it is totally clear, because is may be partially clogged,
letting a little fuel through, but not enough to accelerate.

If it looks like you need a new kit or any parts, ask the Stihl dealer the price of a new carb, as many of these models, they have dropped the price of a new carb just a few dollars above the price of a new kit.

Wouldn't the "symptoms" be the same if the fuel line from the tank to the carb had a small hole/slit in it?

Thanks for responding, Fish.

 

[Fish]

It would probably be a big hole if it wouldn't pull any fuel, take it out and inspect it, if the part that dangles in the fuel is real soft and gummy, it should be replaced as well.

 

[vettman]

It would probably be a big hole if it wouldn't pull any fuel, take it out and inspect it, if the part that dangles in the fuel is real soft and gummy, it should be replaced as well.

Well, I took the carb off, blew out all the passages, re-assembled, installed and it's running like it should. Like I said in the original e-mail, this 5 year-old unit probably has less than 10 hrs. of use, and it's always "winterized" according to the owner's manual. This trimmer was made in China, as is a lot of Stihl equipment. I don't think I will ever buy another Stihl product. I had bad luck with their handheld blower, and now the hedge trimmer. I've had much better luck with my Husqvarnar equipment--a chain saw and string trimmer. The string trimmer is 10yrs old this season and I've never had a single issue with it. My 20 year-old Shindawa backpack blower still starts and runs like a new one. Another issue I have with Stihl is the difficulty in locating parts lists. I don't mind patronizing dealers, I just hate to make a trip to get a part number and/or a part. It's much more convenient for me to shop online. The Stihl owner's manual encourages you to go to a dealer for just about all routine maintenance. Some of us have the tools and knowledge (with some support from forums like this one) to do most of the things needed to keep our equipment in good repair. Pardon me for venting.

 

[Fish]

Yeah, on a few of the Chainsaw forums I have started a "Mediacat Chain Letter" thread, so everyone can get a 2012 version of
Stihl's Mediacat, which is the full parts lookup dvd, and also has all of the newer mechanic's manuals, the "Holy Grail" for
Stihl nuts.....

I would try that here, but this is a weird crowd here.

 

[Fish]

Well glad to hear that you got her running good. I figured a little light cleanup was all it needed.....

 

[Fish]

Just go to bing and type in "Mediacat Chain Letter" and it will come up. You have to join, then request a copy, and promise to agree to send out 2 copies as well to keep the chain going. Mention my name, and someone may have something to say......