Behind the times - first weed trimmer - trouble starting Bolens BL100

[lakelover]

I got a fairly new, free Bolens BL100 gas weed trimmer. I know it's a throw-away low end model. I hope to get at least some use out of it. I replaced the recoil starter. Now that works well, but it's not starting right.

Instructions say:

1. Prime 10 times
2. Choke position 1; pull rapidly 5 times
3. Then choke position 2, squeeze throttle and pull til it starts.
4. Keep throttle wide open for 15-30 sec. until it warms up, then switch to choke position 3: ready to use.

Here's what it does:

After priming, while pulling rapidly in position 1, it often starts at that step. If I put it in position 2 at that point, it will run for several seconds and then die. Either that, or if it stays running, as soon as I depress the throttle, it dies. It does this wither in position 2 or 3, if it has stayed running to that point.

Obviously a fuel problem, where should I start with this?

 

[dingbat]

Re: Behind the times - first weed trimmer - trouble starting Bolens BL150

Re: Behind the times - first weed trimmer - trouble starting Bolens BL150

Time to rebuild the carb

 

[lakelover]

Re: Behind the times - first weed trimmer - trouble starting Bolens BL150

Re: Behind the times - first weed trimmer - trouble starting Bolens BL150

I figured as much, I'll look into it, thanks.

 

[CharlieB]

Re: Behind the times - first weed trimmer - trouble starting Bolens BL150

Re: Behind the times - first weed trimmer - trouble starting Bolens BL150

Depending how old the unit is, alcohol in the fuel causes the fuel pump diaphragm in the carb to harden, and will not pump much fuel.

A carb kit should restore function just be very careful not to switch the idle and main jet needles and be very careful to count their # turns in to a lightly seated position so you can return them to their exact same position, this will save you greatly in readjusting mixtures once running again.

 

[lakelover]

Re: Behind the times - first weed trimmer - trouble starting Bolens BL150

Re: Behind the times - first weed trimmer - trouble starting Bolens BL150

Good tip, thanks. I'll take it apart and see how things look.

 

[Limited-Time]

Re: Behind the times - first weed trimmer - trouble starting Bolens BL150

Re: Behind the times - first weed trimmer - trouble starting Bolens BL150

Check the screen in the muffler. These often times plug up and cause the issues you are having.

 

[lakelover]

Re: Behind the times - first weed trimmer - trouble starting Bolens BL150

Re: Behind the times - first weed trimmer - trouble starting Bolens BL150

Thanks, will do.

 

[lakelover]

Re: Behind the times - first weed trimmer - trouble starting Bolens BL100

The previous owner said it wouldn't start and pointed me in the direction of the recoil assembly, which I replaced. But I have no idea if or how much he messed with it before I got it.

I took things apart, the carb is very clean & not gunked up & gaskets look really good; I hit it with some carb cleaner anyway. I also checked the screen on the muffler, all clear; messed with the idle speed adjustment and got it to stay running for longer, but dies as soon as I hit the throttle. So I hit it with a little shot of carb cleaner while it was running, it stalled, and now it won't start again. I need to get the screw readjusted. Anyone know the initial idle speed screw adjustment setting on these?

I'm guessing the machine is around 7-10 years old at this point and if I can't get it running without putting more $$ into it, I'm going to give up on it, so would like to give it one last shot.

Edit: Got it running and idling again, the idle is very uneven, but it will stay running. Is anything supposed to be in that hole in the pic below?

 

[Big Bubba]

Re: Behind the times - first weed trimmer - trouble starting Bolens BL100

Lakelover,
Looks to me your missing the high speed adjustment mixture screw that should look like the screw above that hole. Your missing that adjustment screw and that could cause it to not runm right. You might have to go to the local small engine parts place to get that missing screw.

 

[lakelover]

Re: Behind the times - first weed trimmer - trouble starting Bolens BL100

Thanks, I was wondering about that. It would make sense why it won't run at high speed for more than a couple seconds.

 

[Big Bubba]

Re: Behind the times - first weed trimmer - trouble starting Bolens BL100

lakelover, Yeap, that is it. That high speed adjustment screw has to be in there for it to run right. Looks like someone broke it off and it will be hard to get the remainder out. I wonder how much another carb for it would cost since that piece is broken off?

 

[Big Bubba]

Re: Behind the times - first weed trimmer - trouble starting Bolens BL100

Lakelover, is the screw that is missing, broken off or is it completely been unscrewed or removed out of that hole? If it has been completely removed see if you can find another screw, maybe, try a local small engine parts store or maybe the salvage yard for lawn mowers if you have one.

 

[lakelover]

Re: Behind the times - first weed trimmer - trouble starting Bolens BL100

It's hard to see in the picture, but I think the screw is just missing, not broken off. I can look down into it and see gas in the bottom of the hole. So I'm thinking my only hope is to try to replace the screw some way. New carbs for that model are $36 & up, so I won't go that route. I'd sooner buy a new machine. Thanks.

 

[Alwhite00]

Re: Behind the times - first weed trimmer - trouble starting Bolens BL150

Re: Behind the times - first weed trimmer - trouble starting Bolens BL150

Check the screen in the muffler. These often times plug up and cause the issues you are having.

x2 - i have a Ryobi that is going on 10 years old, After the first year it was running like crap, I took the plugged up screen off the muffler and it's still running strong.

LK

 

[CharlieB]

Re: Behind the times - first weed trimmer - trouble starting Bolens BL100

Straighten a paper clip and gentle probe the hole to make sure it is full depth. Some carbs only have the one adjustment, the other is a fixed oriface inside the carb. If the paper clip probe will go in over a half inch then a second test is to take out the existing jet and screw it in, if the hole is threaded then for sure you are missing the jet.

Go to your nearest small engine/lawn mower repair shop and ask if you can have both jets from a dead weed wacker. Tell him you dropped it in the yard and can't find it. Get the small spring under it, it is necessary to keep it from vibrating and turning, changing the adjustment.

See which one is the same as the one you have, screw the other on in and set initially to 1 and 1/2 turns out from lightly seated.