I have a TB20CS trimmer that suddenly just stopped the other day. I discovered there was no spark so I installed a new coil, gaped it with a business card and it started right up but it would not rev up at all. It'll idle perfectly but not high enough to trim. So I've done the following:
1. Installed a new Champion Plug
2. Replaced all the fuel lines including the filter
3. Replaced the carburetor with a new one
4. Drained and replaced the fuel.
5. I removed the intake and inspected the Reed Valve. It appears to be OK, has a slight bow like it's supposed to and appears in like new condition. It's stainless steel.
6. Checked the compression and it's slightly over 120 psi.
7. Removed and checked the spark arrestor
8. Ran without muffler to verify it wasn't plugged
It'll run at WOT but it runs like the mixture is not correct, no power and won't rev up, but if the high mixture needle valve is adjusted it'll stall out. It reacts exactly the same with either carb. Idle is fine.
Any ideas?? (Besides throwing it out!!)
1. Installed a new Champion Plug
2. Replaced all the fuel lines including the filter
3. Replaced the carburetor with a new one
4. Drained and replaced the fuel.
5. I removed the intake and inspected the Reed Valve. It appears to be OK, has a slight bow like it's supposed to and appears in like new condition. It's stainless steel.
6. Checked the compression and it's slightly over 120 psi.
7. Removed and checked the spark arrestor
8. Ran without muffler to verify it wasn't plugged
It'll run at WOT but it runs like the mixture is not correct, no power and won't rev up, but if the high mixture needle valve is adjusted it'll stall out. It reacts exactly the same with either carb. Idle is fine.
Any ideas?? (Besides throwing it out!!)