Shindaiwa bogging down

[OldTermite]

Need some help, guys. My usually dependable T27 is sick, started bogging down mid-day on Sunday. After cutting strong for two hours or so, it started bogging down when I gave it full throttle, almost like it was being choked. Same fuel, same mix from same cannister. I've never had to work on it so I'm not sure where to start looking. Anyone think it might be a clogged fuel filter? Bad mix? Air filter?

Also, the head has gotten to where it spins constantly, even at idle, and it seems like Cutter1 had posted here previously that the likely culprit is the clutch. Is that a reasonable home repair or do I just need to bite the bullet and give it some shop time?

[AWR]

sounds like the screen in the muffler try to take it out its full of carbon

[OldTermite]

Thanks, hadn't thought of that but now that you mention it, my Stihl chain saw acted similarly and that was, in fact, what the problem was. I'll check it tomorrow and see if that does it.

[lawnspecialties]

Although I can't recommend this so you won't burn down a forest, you'll find most guys here on LS pull the spark arrestors the day they buy any handheld equipment.

[Lawn-Scapes]

You might want to take the exhaust off and see if there is carbon build up in the port. If so.. you'll want to clean it out. Make sure the piston is in the down position and scrape it with a small screwdriver. Blow out with compressed air through the sparkplug hole.

[lawnspecialties]

You might want to take the exhaust off and see if there is carbon build up in the port. If so.. you'll want to clean it out. Make sure the piston is in the down position and scrape it with a small screwdriver. Blow out with compressed air through the sparkplug hole.

I've had this happen once before on an old RedMax. Good advice.

Power robbing problems:
old fuel filter
nasty air filter
clogged spark arrestor
carbon build-up in exhaust port
crack in fuel line (especially check around clamps)
crack in primer bulb
old spark plug

[OldTermite]

Exactly the same advice I received when I took my chains in for sharpening. I followed that advice and the saw has run strong ever since . . . and not one fire! ! Thanks for your input.

[White Gardens]

The clutch sounds like it's locked up. You can usually get a repair kit for them. Easy fix. Be careful though, if you use it with a locked clutch then you might break the drive shaft.

[K/B]

You might have a cracked fuel line. That will cause it to run lean, (high idle) and poor power.

[OldTermite]

Hmmm . . . bought this T27 used, whoever had it before me had already removed spark arrestor, so that ain't it . . . didn't appear to be any significant carbon built up in cylinder. Cracked fuel line or frozen up clutch are probably the next good suspects, I'll check them this evening or tomorrow. The head has continued to spin even at idle, although at a reduced RPM, and I figured that was the clutch hanging up a little. It makes sense that if it was already failing it could have degraded further to where it just doesn't release . . . does that make sense? Did someone post here that it was about a $20 shop repair? That would be alright if it solves the problem.

Thanks for all of your suggestions.

[MowerMedic77]

Also, the head has gotten to where it spins constantly, even at idle

Yes this is your clutch, very common on the T27. Probably no cutter guard on the unit and the line has been run too long and the brake like material on the clutch shoes is gone causing the clutch to open wider then normal to make contact with the clutch drum braking the center spring.

[kayeproperties]

Yes the clutch spring is broken. They are a few bucks if they stock them or you can get a new assm with spring and shoes I think for 30 bucks or so. not a bad job but if you dont repair it it can cause more damage and its really hard to use.

[totallawncare25]

I have rebuilt a many of these and the T270's.... When you take the clutch assembly off the front of the motor if your spring is on the shoes and the clutch shoes look like they still have brakepad looking material on them then all that is good.. Secondly look at the clutch drum itself if it has wore a groove into it like a break rotor does on a care you need to replace just the drum.. But you are that far in you might want to replace all of it.... UP TO YOU.. Thirdly have you tried adjusting the high fuel mixture screw on the carb??? Those carbs can get clogged up and you might just need a new carb on the trimmer... Rebuilding them isnt fun and if you dont know how to do it correctly you are just throwing your money away.. you could also have a leaky fuel tank grommet... If you were closer to me id fix it for ya as im just outside nashville.... Ryan

[jkilov]

Yes this is your clutch, very common on the T27. Probably no cutter guard on the unit and the line has been run too long and the brake like material on the clutch shoes is gone causing the clutch to open wider then normal to make contact with the clutch drum braking the center spring.
The guard is usually broke & junked fairly quick on the T27. It's also a very powerful machine so people tend to run them low rpms riding the clutch.

I had an employee once who would ride clutches on stuff all the time and just would'nt listen. Ended up tuning the idle screw as high as it would go on the trimmer he used the most so it would spin all the time.

Once the friction coating is gone the shoes should to be replaced.

[OldTermite]

Per advice of several on the board, I removed and replaced the clutch and, having done so, I now understand how this type of clutch works. Both shoes were worn nearly completely away. However, new clutch didn't solve this problem. The trimmer starts fully choked, no matter where I have the throttle lever (wide open or hands off), but then after a few seconds when I slide the choke off like I used to it bogs down, especially if I throttle up. Also, despite the new clutch, the head still spins constantly. Could this be a problem with the throttle lever/cable?

Oh, and for those keeping score, the clutch assembly cost $49 and change (ouch!) at Cox Power Equipment in Knoxville, seemed high but they're my nearest Shinny dealer.

To summarize, new clutch easy to install, didn't fix the problem. Trimmer head still spins constantly as though it's locked up.

[punt66]

Per advice of several on the board, I removed and replaced the clutch and, having done so, I now understand how this type of clutch works. Both shoes were worn nearly completely away. However, new clutch didn't solve this problem. The trimmer starts fully choked, no matter where I have the throttle lever (wide open or hands off), but then after a few seconds when I slide the choke off like I used to it bogs down, especially if I throttle up. Also, despite the new clutch, the head still spins constantly. Could this be a problem with the throttle lever/cable?

Oh, and for those keeping score, the clutch assembly cost $49 and change (ouch!) at Cox Power Equipment in Knoxville, seemed high but they're my nearest Shinny dealer.

To summarize, new clutch easy to install, didn't fix the problem. Trimmer head still spins constantly as though it's locked up.

you need a carb.

[vgshopboss]

It sounds like you are starving for fuel. Lots of options there.
1. Plugged carb fuel passages
2. Cracked fuel line
3. Plugged fuel pickup/filter
4. Missing or failed gasket between carb and cylinder
5. Cracked carb adapter between carb and cylinder

I would start by replacing the fuel line and installing a new filter. Then if you can get the machine running, spray a little carb cleaner around the gasket mating surfaces and listen for any change in how the trimmer runs. If there is no change, it is relatively safe to say that you aren't sucking air. At that point, pull the carb and either kit it or replace it depending on your own preference. The fuel pump diaphragms in the carbs will wear out over time, and not give you enough fuel.

As to your clutch problem, did you check the clearance between the clutch drum and the shoes prior to installing the new clutch? is the remainder of the old clutch sprayed all over the inside of the clutch drum, making it smaller than it should be, and therefore causing the new clutch to hang up? Seen it on chainsaws before. Good luck.