2006 KTM 990 SuperDuke

2006 KTM 990 SuperDuke
2006 KTM 990 SuperDuke

Motorcycle Junkie

Motorcycle Junkie
2009 Yamaha WR250X

2009 WR250X dressed in street attire

2009 WR250X dressed in street attire
2009 Yamaha WR250X

2003 DR650

2003 DR650
2003 Suzuki DR650

Thursday, August 4, 2011

Squeaky starter motor - an easy fix.


Late last fall when the mornings turned quite chilly (frost on the ground) the starter on the DR began to make some funny sounds, similar to that of a wheezing duck -- a kind of sqeaky, squealing noise. It sounded exactly like this video I found on YouTube:





After reading of similar complaints from other DR owners on ADVRider, the diagnosis sounded plausible:  dry armature inside the starter motor. Requires a bit of lubrication. The end of the armature opposite the drive gear rests in a bushing (not a bearing). Apparently these bushings are made of a sintered material that contains some type of lubricant, whic is released slowly as the sintered material wears away, thus providing a permanent lubrication system. However, if the sintered material gets heated up or burned, it glazes over which prevents the sintered material from lubricating the shaft properly. In warmer weather, it doesn't matter much but when the cold weather hits, the dry rubbing makes a squeaky sound. I guess the best solution would be to replace the bushing in the end cap of the starter motor. But an easy fix that will last a couple of years is to simply put a dab of grease in the bushing. This quick and easy fix takes about an hour and costs nothing. It's also a good way of checking the internals of the starter motor, especially the parts that normally wear out (like the brushes).

First step: because you will need to remove the Cam Chain Tensioner (CCT) it's important to make sure the engine is at top dead centre (TDC) on the compression stroke. To do this, remove the plug on the flywheel cover so you can line up the timing mark. Then rotate the engine by hand (using a ratchet on the flywheel, or by turing the rear tire slowly with the bike in 3rd, 4th, or 5th gear). Remove a spark plug and keep your finger over the hole so that you can tell when the air in the cylinder is being compressed.

The timing mark on the flywheel as seen through the inspection hole.


I also use a plastic drinking straw in the spark plug hole
to make sure that the piston is at the top (but you need to be
sure it's at the top ON THE COMPRESSION STROKE.
That's why you keep your finger over the hole).


As a safety precaution, it's a good idea to disconnect
the + positive terminal from the battery.
Remove the exhaust header pipe

Remove the upper and lower bolts for the oil line
and move it out of harm's way.

Moving the oil cooler line out of the way gives
unobstructed access to the starter motor.
I like to put the bolts and crush washers back in
place to avoid losing them, and also to avoid getting
dirt inside the engine.

Remove the cam chain tensioner (CCT)

Then, remove the starter.

The starter motor removed.

End cap removed reveals the brushes as they are pressing
against the commutator with the wound springs.




A small dab of grease squeezed into the hole at the end of the armature.

A small dab of grease in the end-cap bushing.

I cleaned the guts of the starter using air compressor to blow the dust out.

Cleaned the rubber O-ring and cleaned up the casing a bit.

Wiped down all the grease and crap from the engine.


Getting ready to wind up the spring in the cam chain tensioner (CCT)
**note the long shaft sticking out: it needs to be wound back in before re-installing the CCT.

Remove the bolt that plugs the hole at the end of the CCT (right side in the photo above, bolt is removed)
This exposes a small flat screw inside. Use a small screwdriver to wind up the spring as you push in with your thumb. Keep turning the screwdriver slowly until you hear/feel a click. Then the pin is locked in and you can take your thumb off the end.
CCT pin is locked once the spring has been wound up with a flat scredriver.
Reassembly:
1. install the starter and clutch cable bracket
2. install the CCT and then use the flat screwdriver to unlock the spring
(which will apply tension on the cam chain)
3. re-connect the oil cooler line.
4. re-install exhaust header pipe
5. re-connect positive battery terminal


All buttoned up.

10 comments:

  1. Nice work, no squeak here yet.

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  2. those bushings are either oil or graphite impregnated. i noticed on the forum someone drilled a hole in the back cover for a grease fitting, he wouldn't get much grease in there.what if you drilled a small hole for a couple of drops of some super lube or oil every time it got noisy.you would need to plug the hole of course.

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  3. Well, that could be done, I suppose. But considering the reasonably small effort to remove the starter motor, I'd probably just be willing to repeat the very same procedure again. I don't think it took more than an hour to perform the entire job. Plus, when you've got it all apart, it's a good way to check the overall condition of the starter. As long as I don't have to do this every year, then I'd just as well take it apart to grease the bushing. Wasn't a big deal.

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  4. If the bushing is meant to wear away and provide lubrication with it's "shavings", then wouldn't a more permanent solution be to take some steel wool and buff out the glaze? Just wondering if anyone has tried this.

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  5. Its funny the DR650 manual doesn't mention to put the motor into TDC before starter motor removal??

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  6. True enough, I suppose it's not required, but I prefer to play it safe. Because the cam chain tensioner must be removed in order to remove the starter motor, I like to place the engine at TDC before I begin just in case. It will just make things easier should things go wrong (ie, having the timing change jump a tooth or two) but that shouldn't be a big worry since you shouldn't be turning over the camshafts or the crank during this procedure with the chain tensioner removed.

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  7. TDC is where the chain will be the tightest.Chain may jump if there is too much slack in it

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  8. True, but with the tensioner removed, there will be plenty of slack regardless of TDC or not.

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  9. very good point, my starter been doing this since my bike had done only 1,500 klm almost new, i got bike in 2010 new. im up to 7000 klm ish. im going to have a crack at doing my starter, was hoping not to have to take tensioner out, thought might sqeeze it out past tensioner. yer the tdc bit, yer i recon should not matter were timing is, its just removal of a starter as long as motor is not turned over all should be sweet.

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  10. this is an exellent page too by the way. very well done.

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