Troy Bilt tb20cs

[thegrinch]

Hello and thanks in advance for any tips.

I went to start my trimmer this year and actually this started late last season where the trimmer would fire immediately and then run only for a few minutes at a time until it was 'warmed up' for lack of a better term. Well this year it wouldn't even fire so I thought it was a fouled plug. I went out and bought new air filter, fuel filter and plug for my gas powered equipment including the trimmer. I replaced the spark plug and it fired right up, but again would only run for a few minutes and then die. So I decided to replace the fuel filter. Now, the trimmer won't even fire. I can see gas going through the fuel lines when I prime it so I'm thinking too much air could be getting in but where?

Any ideas?

 

[ILENGINE]

Put your ear close to the carb, and while pumping the primer see if it sounds like the air is being sucked through the center venturi area of the carb. If so then you have a check valve stuck open and will most likely have to replace the carb to fix.

 

[thegrinch]

Thanks,

So I was going to by a can of starter fluid and see if could get it to start that way but before doing so I decided to give it one more try.

I've tried to start it a few different times between my first post here and now, and it never fired. Today, I went out, emptied the tank, filled it about half way, primed it and it started. It took about 10 minutes for it to stay running and another 5-10 minutes for it to feel like it was running at full RPM. I'm certain I'll go through this again, so I guess I'm back to my original problem that started last year.

It takes about 10 minutes for the engine to warm up and stay running. It takes an additional 5-10 minutes for it to feel like it is running full RPM if that makes sense. That's why I thought maybe a new fuel filter would fix this, but I'm back to square one. Do you think I should run some carb cleaner through the gas tank?

 

[ILENGINE]

Carb cleaner in the fuel wouldn't hurt anything. Your last post gave me a hint of something. Could you get me a compression reading with the engine cold, I am starting to wonder if this isn't more compression related than fuel.

 

[thegrinch]

Thanks for the reply,

I don't have a compression tester so I'll have to borrow or rent one. What is really odd was/is this thing when it does decide to run, it starts with a few pulls but again takes about 10 minutes to stay running and an additional 5-10 to get to full RPM. I went and bought some pre mix 40:1 in case I've messed that up but my other 2 stroke stuff runs fine so I doubt that is it.

 

[ILENGINE]

Check compression when you get a chance. If that checks out to be above 90 psi, you may have to replace the carb to even getting it to run half way close to correct. running lean will cause loss of speed, and explains a lot of the symptoms. so the carb is a possible problem.

I have to do multiple warranty handheld exchanges every year because of your exact problem.