Starter/Generator Rebuld or?

Rales · #1 10-20-2011, 02:30 PM

My 169 has recently started having a little harder time turning over the starter/generator. If it tries to start on the compression stroke it will not go. I have to hand rotate it past the compression stroke then try agan and it will work fine. I recently put a new battery on it to see if that may have been the issue since it was an older battery but no change.

As far as rebuilding the starter/generator do I simply clean it and put in new brushes or should I take it to a shop and have them go over it more involved?

A couple months ago I had the starter/generator off and apart, I cleaned it then and relubed everything. The brushes still looked to be in good shape as there where pretty long but I am not sure how long they are when new.

It appears to be charging just fine otherwise.

Thanks

Dave

_DX3_ · #2 10-20-2011, 03:23 PM

Have you checked to see if the compression release is working correctly?

You might also want to check to see if the static timing is correct.
http://mgonitzke.net16.net/tools/static_timing.pdf

Is the S/G belt tight?

Rales · #3 10-20-2011, 04:30 PM

I have not checked the compression release as i am unsure how to check that with the head still on the tractor or by removing the side valve cover. Is there an easier way? I have a compression tester I could hook up if that may assist. I assume if the compression shows really low then it would be working corretly?

The belt is tight, and the timing I reset about 3 months ago. It would not hurt to double check that.

_DX3_ · #4 10-20-2011, 04:35 PM

With a tester it would be low, not sure on how much tho. The only other way to know is as you said, remove the head to see if the exhaust valve is raising slightly on compression stroke. Or you can remove the carb and valve cover and watch the exhaust valve to see if it is working correctly.

Are all of the electrical grounds nice and clean touching clean bare metal? You might try checking and polishing those connections especially from engine to frame, and battery to frame. One from battery to engine would help too.

Just simply thinking of some ideas that might help.

Matt G. · #5 10-20-2011, 05:32 PM

Check your grounds and positive battery cables first...they are easier to try than the ACR and cheaper than going through the S/G for possibly no reason.

If it starts the tractor and charges, the only thing you'd really need to do is clean all the carbon dust out of the inside, replace the brushes, replace the ball bearings if equipped and they are rough, and clean up the commutator and undercut the mica.

Rales · #6 10-21-2011, 02:32 PM

Thanks guys. I had checked the cables and they looked good when I had them off a while back but I will go over them all again and clean them up just to make sure. I may also do a resistance check on the cables to see if maybe one of my cables is going.

I also checked the timing and its dead on. Checked it via the manual and also through a timing light on it just to see and it was dead on.

I will update once I am able to get it fixed.

Thanks again for the help, its greatly appreciated!

Ash_129 · #7 10-21-2011, 03:09 PM

Is the spark plug located above the exhaust valve on your 169? If so, you can just remove the spark and spin the engine by hand. As you roate the engine over you will see the normal exhaust valve lift, and also a much smaller lift. The much smaller lift is the ACR.

Also, if it is the ACR that's the culprit, the engine should crank over by the starter much faster with the spark plug removed (for testing purpose).

Cheers.

Rales · #8 10-21-2011, 10:18 PM

Ash, I do believe its over the exhaust valve, thats a very good idea to be able to check that. I will be checking the wiring shortly and will also try that out.

Thanks for the great ideas!