Troy-Bilt TB675EC Trimmer

[chucketn]

Have a TB675EC trimmer with no spark. Plug was tested in another trimmer and has spark. Any diagnostics I can do to test ignition module, or do I just replace it? What about the air gap? What should it be? Is it adjustable?

Chuck

 

[motoman]

I have only owned Ryobi and Sears trimmers. My Ryobi failed at year 10 with no spark. There was flywheel contact with the coil module shoes. Look for marks on yours. Coil modules can fail from over heat. I don't think there are testers for the coil. Side by side the new Sears would produce a 1/8" spark, the Ryobi none across an old spark plug with only a side electrode (poor man's spark tester)

 

[bertsmobile1]

Have a TB675EC trimmer with no spark. Plug was tested in another trimmer and has spark. Any diagnostics I can do to test ignition module, or do I just replace it? What about the air gap? What should it be? Is it adjustable?

Chuck

The only test for a module is to disconnect the cut out ( thin ) wire and make sure it has no connection to earth.
Then spin the fly wheel and look for a spark.
A nut driver in a battery drill on the fly wheel nut works well provided the plug is removed and earthed out so you can see the spark
Or you drain the fuel and test with an inline tester, plug in.
You do not want it to start with the drill on the flywheel nut.
The module will either work or won't work.
If you get a spark then warm the module with a hair drier and tet again as they oft break down when hot before giving up the ghost all together.

With Troy built you will find the new module will be about 1/2 the price of a new trimmer so it is a close call fix or replace

 

[7394]

With Troy built you will find the new module will be about 1/2 the price of a new trimmer so it is a close call fix or replace

My Troy-Bilt TB20CS needs at least a new carb, Trimmer was $79. special 9 + years ago.. I think I'm just gonna try & sell it off as a parts machine. I'm surprised it lasted this long, I did help it along mechanically tho.

 

[chucketn]

Well, I purchased a new ignition module from jacks Small Engines. Finally came in today. Also got a couple of plugs and a spark Tester. got the new module installed, and still no spark. Have disconnected the kill switch leads from the module, still no spark with tester or spark plug. Air gap was set with 2 business cards that measured .020 together. What next? BTW, module was $12.95 less shipping.
This weed eater is less than 2 years old, and was purchased to fit additional tools I have, tiller, hedge trimmer, etc. It also has an easy start feature by using an adaptor in a cordless drill, handy for this old duffer.

Chuck

 

[chucketn]

Anyone have any ideas on this one? I have taken resistance readings on the new and old ignition modules, anyone have the specs?. While changing out the module and testing, the red cover with the primer bulb on it fell off and disconnected the hoses. Can't find a diagram that clearly shows where they go, anyone got a clue?
Help! the grass is getting up to my *****! and the wife is on my back... I'd hire it done, but no funds... No teenagers in the neighborhood willing to work forbubble gum money, LOL!

Chuck

 

[ILENGINE]

Try setting the air gap clearance at .010 for the modules. And the fuel one from the carb to the primer attaches to the sbort nipple on primer. the long nipple is the fuel return to the tank.

 

[chucketn]

Try setting the air gap clearance at .010 for the modules. And the fuel one from the carb to the primer attaches to the sbort nipple on primer. the long nipple is the fuel return to the tank.

Thanks, ILENGINE. I did try the air gap with 1 business card, and the module laminations hit on the flywheel fins. Are you saying the module air gap is less than .020?

Chuck

 

[motoman]

At this point I would make sure the magnet is secure on the flywheel. You probably have confirmed that the module is IDENTCAL to the removed one, because the sweep point of the magnet must be correct. Finally, I know jack's has a good rep for parts, but the electronic devices inside the module are important . By that whether they are hobby grade parts or have been screened by the mfgr for temp performance. On this subject you are entirely at mercy of the seller who , himself, cannot know how reliable the parts are. I mention this because $12 is awfully cheap. Seems like my Ryobi module was around $35 (assuming worth it) . China produces lots of good appearing , low grade stuff. I think everyone knows that most electronic devices are made in Asia , so it is not the country, but the process.

 

[chucketn]

I have an older TB575 that still makes spark, but won't start. I think it has a dirty carb. I'll concentrate on that one if resetting the module air gap doesn't work. Tried to take it apart to see if it's module would fit. Can't get the clutch off to get the cover off to get to the module...

I will recheck the flywheel magnets. I think the TB675 had a fall of about 3 ft off a shelf it was on. I found it on the floor and don't remember leaving it there.

Thanks for the help folks. Seems with my present financial situation, a military career was a poor choice. At least with my military benefits and Medicare, I do have good medical coverage.

Chuck