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Stator and Starter clutch LocTite fix

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This preventative Maintenance "fix" is applicable and recommended for all year and model year DRZ 2000 -2014

 

The DRZ has proven over many years to be a reliable platform, though there are a few have to, need to preventative maintenance areas.
This thread will address one of those areas. Stator and starter clutch fasteners. There has been history of the hex head fasteners that hold the stator to the cover, and the fasteners that hold the starter clutch to the flywheel to vibrate loose. When this happens, the result is a destroyed stator, flywheel and sometimes starter clutch and cover.
A quick search through the DRZ forum using search words like “stator” “bolts” “destroyed” and you’ll see this is not a single user isolated issue.

The preventative fix is simple, low cost and effective.
Basic hand tools, impact screwdriver W/#2 & #3 phillips bits thread locker, recommend med strength Loctite 242 or equivalent for the stator bolts and high strength Loctite 271 for the starter clutch bolts. Permatex also makes a commonly available threadlocker in Medium and High strength as do several other companies.

The stator fasteners:
First problem, why won't the cover come off when I've removed all seven visible bolts? Answer: there's an eighth bolt hidden inside the starter gear cover. You have to get out the impact screwdriver W/ #3 bit and take those three JIS  (kind of like Phillips) head screws out.

 

 

An Impact driver works best for this, if you go with a standard phillips screwdriver without the impact tool - don't be surprised if you damage the heads.
startergearcover-1.jpg

Once you remove the starter torque limiter and its cover out this is what you'll see this
startergearcluster-1.jpg
If the torque limiter doesn't come out with the cover, just take hold of it and pull it out. Do NOT remove the circlip on the shaft - leave the cluster intact. Another thing to be alert for - there's a bushing in the center of the cover and another behind the torque limiter (in the cover itself).

Here's the hidden bolt (red arrow), along with the inner pilot bushing (green arrow) that can drop out and get lost when you turn the stator/cover over. The other bushing is in the starter gear cover itself.

starterbushinghiddenbolt-1.jpg
 

The stator fasteners 
drz-stator-loctite1.jpg
To gain access to these bolts you have to remove the stator cover. Yes there is supposed to be oil in there, do not panic when you remove the cover and some oil dribbles out. The longer the motor has sat not running, the more oil you will find drained back to the motor. Suggest draining remaining oil when you're done and side cover is back on, good time for an oil change is after you have had the motor open. To otherwise minimize oil loss, start the bike just prior to doing this project. That will move most of the oil into the frame tank.

 

You can also lean the bike over to the right to further minimize oil loss. If you drop in two full quarts or liters when you do an oil change, you really should be fine with what little oil you lose doing this job.

The gasket is a metal core & fiber covered. It is reusable in almost all cases. The cover will take some pulling to overcome the magnets in the flywheel, and there are two dowel pins used to locate the cover correctly. You must evenly remove the cover so as to not bind it on the dowel pins. Often the cover will bind where the starter goes through from the right side. To assist getting the cover off, loosen the starter bolts, and or remove the starter, then tap the cover and lift it away evenly from the case.

Once the cover is off, remove stator the fasteners you see in the picture above, clean with some Brake Clean or like solvent, clean the hole the screw goes in to, dry.

Place a drop of med strength thread locker on the screw and reinstall. Repeat for all three screws.

 

Take care to replace the metal wire guides correctly, as you see in the above picture.. The cable MUST be under the metal guide and the guide fully seated in place.

Correct installation 
correct DRZ stator install.jpg
Next; Starter clutch / flywheel fasteners:
drz-starterclutch-lt1.jpg

This is an edited pic from the service manual... This picture shows the recommended placement for the two shims used with the starter idler gear.
1547615086_updaedsuggestedDRZstartershimorder.jpg.19d4653f4436b79c83d8c6e41f9186a6.jpg
One shim on either side of the circlip. The manual and parts fiche shows one shim on the motor side of the gear.. that is wrong. If placed there, often what you'll find is the shim broke and in the motor, or stuck to the stator magnets.

The 6 socket hex head cap screws have been the cause for more than one destroyed stator, flywheel and starter clutch.
Exactly why they back out or shear is open for discussion. Simple vibration is one reason for sure. Another is, when you stall a DRZ motor and the motor is forced backwards say while on an incline on your SM or off road while climbing a hill the motor stalls, you'll hear the “gear whining" sound as the motor is actually turned backwards. The flywheel /starter gear assembly shift slightly as the fastener holes in the flywheel are larger then the 6mm fastener. Upon going forward again under power, the assembly shifts again.

Shearing these fasteners is a common occurrence on the LTZ (ATV version of the DRZ) due to the same forces applied when an ATV spins around backward and the motor gets reversed.

This is believed to be a proximate cause for the starter clutch fasteners loosening or shearing.

If the 6 socket hex head fasteners are tight and in good shape replacing them is not required as long as they are grade 10.9 or 12.9. However, if they have come loose, or simply as an insurance you have the proper grade fastener you can take this opportunity of having the cover off and fasteners accessible to replace them with grade 10.9 or 12.9 fasteners. Buy replacement fasteners from a known trustworthy source, ebay is not your friend here.
 

Add a drop of High strength thread lock to the thread portion that will go into the starter clutch and tighten the  fasteners back up to the proper torque.

M6 x 1.0 , 16mm long grade 8.8 are what the OEM specs for this assembly in some model years. So if using those OEM fasteners your limited to 70 INLB.
 

NOTE, fellow user Noble has provided info that suggests the OEM fastener is in fact a grade 10.9 from factory.
I respect his opinion as I have always found it to be based on fact and personal experience. I can only assume the OEM has used both grades, as I'm positive the fasteners I've replaced in at least some DRZ's were not grade 10.9

In that light, replacement of the OEM fasteners is still recommended, so you know you have a good fastener of known condition and grade.
Use a 10.9 or 12.9 and follow the recommended torque spec’s for your chosen grade. 

10.9 - 120 inch pounds (10 ft lb)
12.9 - 144 inch pounds (12 ft lb)

So discussion of the why is open, the fix that seems to stop the issue is to use high strength thread locker on the 6 fasteners.
The procedure is the same as above for the stator screws.
Remove one at a time, clean, add one drop of thread locker, reinstall
.

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