Help me save my Weedeater

deaconjim · #1 05/03/09, 01:19 PM

I have a Troybilt 4 cycle weedeater. It will run, but only for a few minutes, and you have to pump the throttle to keep it going. It never gets up enough power to do anything. It was running fine, and I shut it off, and when I restarted it a few minutes later, I started having problems.

I first assumed it was the fuel line, and replaced it. I have since replaced the carb, but nothing changed. I took it by the local small engine shop. The guy looked at it, but said it would most likely cost more for him to fix it than I'd want to spend. He was probably right.

I'd like to at least try to save it before I buy another. I'm not too proficient with small engines, but I figure I can't hurt it any worse than I would just by throwing it away.

Any suggestions on where to start?

JayandTanya · #2 05/03/09, 01:26 PM

Quote:

Originally Posted by deaconjim

I have a Troybilt 4 cycle weedeater. It will run, but only for a few minutes, and you have to pump the throttle to keep it going. It never gets up enough power to do anything. It was running fine, and I shut it off, and when I restarted it a few minutes later, I started having problems.

I first assumed it was the fuel line, and replaced it. I have since replaced the carb, but nothing changed. I took it by the local small engine shop. The guy looked at it, but said it would most likely cost more for him to fix it than I'd want to spend. He was probably right.

I'd like to at least try to save it before I buy another. I'm not too proficient with small engines, but I figure I can't hurt it any worse than I would just by throwing it away.

Any suggestions on where to start?

Hi deaconjim First thing is does it have any compression? If your not too sure what I mean, can you feel resistance on the pull cord as you pull the engine over? If there is resistance go ahead and remove the spark plug from the engine and plug it back into the cap, lay the spark plug anywhere on the engine casting (grounding the body of the plug) and pull the engine over a few times, Check and see if you have spark, check it out and let us know.

deaconjim · #3 05/03/09, 03:06 PM

Quote:

Originally Posted by JayandTanya

Hi deaconjim First thing is does it have any compression? If your not too sure what I mean, can you feel resistance on the pull cord as you pull the engine over? If there is resistance go ahead and remove the spark plug from the engine and plug it back into the cap, lay the spark plug anywhere on the engine casting (grounding the body of the plug) and pull the engine over a few times, Check and see if you have spark, check it out and let us know.

Compression is fine, and so is the spark. My best guess is that it's not picking up the fuel for some reason, but I've run out of ideas.

JayandTanya · #4 05/03/09, 03:26 PM

does it have a primer bulb? if so look for leaks or holes in it. Get a squirt bottle and put a few shots of mixed fuel down the plug hole reinstall plug and see if it fires let us know

deaconjim · #5 05/03/09, 03:58 PM

Yes, it does have a primer bulb, and it does not appear to be leaking. It will pump fuel. It does fire on wd-40 and ether, but it won't run long.

JayandTanya · #6 05/03/09, 04:23 PM

Quote:

Originally Posted by deaconjim

Yes, it does have a primer bulb, and it does not appear to be leaking. It will pump fuel. It does fire on wd-40 and ether, but it won't run long.

Ok first thing first NEVER use ether or quick start or anything like that, all that will do is damage things.

Next thing is now that you know you have spark and compression, is obviously fuel, now with that particular unit im not sure if it has an in tank filter or an inline filter, if it is an in tank filter get a piece of mech wire or something along those lines bend a hook on one end and hook the line in the tank and pull out the filter check it to see if it is cloged at all disconect the filter from the line, and try to blow air through it.

If you have an inline filter fish it out and try the same proceedure

one other thing about the primer bulb is it might not leak fuel but it will leak air thus hindering the sucton

Let me know if that works

HermitJohn · #7 05/03/09, 04:39 PM

I assume this is 2cycle engine. If so it will have an all position diaphram carb like a chainsaw. The diaphram acts like a little fuel pump. Rebuild the carb with a kit, kit will have a new diaphram. The primer bulb thingie is just modern EPA replacement for choke. Guess they think people will run engine with choke half on or something to make up for them requiring carbs to run very lean. So with just primer bulb you can start the engine with richer mixture but cant use the machine while pumping the little bulb. Whatever, its a pain in the rear but way things are done in modern world.

Anyway a new diaphram in carburetor is what you most likely need.

HermitJohn · #8 05/03/09, 04:49 PM

Ok, just reread your initial post, you say you have replaced carburetor with presumably a new one? Suppose you could also get bad new carb. If you got used carb, then most likely it needs a new diaphram. You are not getting fuel if it will run with starting fluid but not from carb. On 2cycle engines the carb diaphram is most likely cause though of course check fuel filter isnt plugged and fuel line isnt collapsing. Modern gas has alcohol and this will destroy older fuel lines, just battled this on my chain saws this winter. You can get bulk fuel line that will hold up, if not locally, then off internet. If fuel line is squishy and almost sticky and stays collapsed long time if you squeeze it with your fingers, then replace it.

deaconjim · #9 05/03/09, 05:00 PM

Quote:

Originally Posted by JayandTanya

Ok first thing first NEVER use ether or quick start or anything like that, all that will do is damage things.

Next thing is now that you know you have spark and compression, is obviously fuel, now with that particular unit im not sure if it has an in tank filter or an inline filter, if it is an in tank filter get a piece of mech wire or something along those lines bend a hook on one end and hook the line in the tank and pull out the filter check it to see if it is cloged at all disconect the filter from the line, and try to blow air through it.

If you have an inline filter fish it out and try the same proceedure

one other thing about the primer bulb is it might not leak fuel but it will leak air thus hindering the sucton

Let me know if that works

The in-tank filter is new, along with the fuel line. If the primer bulb is bad, I can't see the problem. It does move fuel when you prime it. I guess the best bet would be to replace it anyway.

deaconjim · #10 05/03/09, 05:02 PM

Quote:

Originally Posted by HermitJohn

I assume this is 2cycle engine. If so it will have an all position diaphram carb like a chainsaw. The diaphram acts like a little fuel pump. Rebuild the carb with a kit, kit will have a new diaphram. The primer bulb thingie is just modern EPA replacement for choke. Guess they think people will run engine with choke half on or something to make up for them requiring carbs to run very lean. So with just primer bulb you can start the engine with richer mixture but cant use the machine while pumping the little bulb. Whatever, its a pain in the rear but way things are done in modern world.

Anyway a new diaphram in carburetor is what you most likely need.

Quote:

Originally Posted by HermitJohn

Ok, just reread your initial post, you say you have replaced carburetor with presumably a new one? Suppose you could also get bad new carb. If you got used carb, then most likely it needs a new diaphram. You are not getting fuel if it will run with starting fluid but not from carb. On 2cycle engines the carb diaphram is most likely cause though of course check fuel filter isnt plugged and fuel line isnt collapsing. Modern gas has alcohol and this will destroy older fuel lines, just battled this on my chain saws this winter. You can get bulk fuel line that will hold up, if not locally, then off internet. If fuel line is squishy and almost sticky and stays collapsed long time if you squeeze it with your fingers, then replace it.

John, this is a 4 cycle engine, and I have installed a brand new carb along with the fuel line and filter

JayandTanya · #11 05/03/09, 05:05 PM

Can you get it to run by priming it? or fire at least? if you can get it to fire "massage" the primer bulb feeding the engine a little extra fuel to keep it going untill it can take over.

I had another thought...Is this the first time using it this year ? and is it last years gas?

deaconjim · #12 05/03/09, 05:11 PM

Quote:

Originally Posted by JayandTanya

Can you get it to run by priming it? or fire at least? if you can get it to fire "massage" the primer bulb feeding the engine a little extra fuel to keep it going untill it can take over.

I had another thought...Is this the first time using it this year ? and is it last years gas?

First, I haven't used it this year. It died on me at the end of the summer, while I was using it. It was running fine, and I shut it off for a moment, and when I started it again, it wouldn't run.

I'm not sure if pumping the bulb will help, since it won't run long enough to get a free hand to the bulb.

agmantoo · #13 05/03/09, 05:32 PM

Take the muffler off and see if it will run.

deaconjim · #14 05/03/09, 05:41 PM

I appreciate the help folks, but now the starter rope won't rewind, and my patience has run out for the evening. Maybe tomorrow afternoon my desire to fix it will overcome my desire to throw it in the pond.

If it does, I will try the muffler, and anything else anyone can suggest. If not, I'm off to town for another one, and I'll be happy to take suggestions on that as well.

agmantoo · #15 05/03/09, 06:16 PM

deacon, the gas tank has to vent also for gas to get delivered. Maybe try to run the unit with the filler cap loose.

deaconjim · #16 05/03/09, 06:26 PM

Quote:

Originally Posted by agmantoo

deacon, the gas tank has to vent also for gas to get delivered. Maybe try to run the unit with the filler cap loose.

Thanks, I'll give that a try too.

HermitJohn · #17 05/03/09, 08:09 PM

A 4cycle engine on a weedeater? Time has passed me by I guess. It would still have to use a diaphram carb due to changes in angle during use. No way to get a float carb to do that. How they do the oil sump not sure. I guess it would have to be pressurized system and a weighted flexible oil pick up tube that moves as engine changes position. I remember them talking about such since 4cycle engines are easier to get low emissions. But never seen one.

Probably not too distant future till we get computer controlled fuel injection on small engines. At least throttle body injection.

sammyd · #18 05/03/09, 10:43 PM

4 cycle engines have been on weed eaters for some time. I have one in the garage that is 3 years old.

deaconjim · #19 05/04/09, 05:23 AM

Quote:

Originally Posted by sammyd

4 cycle engines have been on weed eaters for some time. I have one in the garage that is 3 years old.

This is my second one. The motor locked up on my last one, and I'd already thrown it away when I found out all I had to do was pull the plug to fix it.

seagullplayer · #20 05/04/09, 06:49 AM

I keep an eye out at yard sales, bought the one I use now three years ago for $15, the one before that lasted about three years, it also was $15...

Bought a used push mower this weekend at a yard sale; $25

These days craigslist is a good place to hunt a bargin, if one can be had on a weedeater this time of year!

I have never worked on a 4 cycle weedeater, I guess you have to pull the air filter off to spray starter in it? Or just pulling the plug? If you have not tried to start it without the air filter, I would. Good luck.