Outdoor Power Equipment (Lawn Mowers, Snow Blowers, Chain Saws and more) Discussions

I bought a 926 PRO in 2005 and love it. especially the remote diff. seems to be worth the money. Unfortunately it has not worked as reliably as I would have thought.

When I pull the trigger the 2nd weel does not always kick in till I swing the machien back and forth. then it does not dis engaege until I do the same.

At first i thought it was just a setting or tention in the cord. I adjusted and saw limited benefit. I cleaned the differential cams to allow them to slide more and it seemed to help.

MY ISSUE IS WITH THE DIFF ASSEMBLY THAT IS PART OF THE GEAR I THINK.

I won another 926pro in a raffle and when i engaged the diff I could not get it to dis-engage. I dis-assembled the diff gear assembly and may have found the issue.

It looks like the assembly has t gears on the ID that have springs in the middle pushing the 2 haves away. when you pull the trigger the cam moves the saft which compresses the diff assembly and the 2 halves of the diff engage. when you release the lever the spring in the diff assy should push it back.

Im looking for help with failure modes. does the spring fail often. Is what i am seeing really the issue? I have no snow blower exp. but im mechanically intuitive and it seems to make sense. Im just looking to see if there could be another issue before I put it all back together...yes it is apart and i cleaned and de-rusted all the parts best i cud.

ANY HELP APPRECIATED

THANKS

bwoz wrote:
Was it installed in the right orientation? The 3 dots on the side of 3 or the 37 teeth should face inward towards the friction disk.

Thanks for the feed back.

I have not re-assembled it yet.  both units i have are less than 3 years old. bought in 2005. I was hoping the gears on the inside would not have worn in that time.

The machine i won in the raffle was neglected a bit and was full of rust. and im thinking that is waht may be causing a problem with the diff.

Friiy- you mention the assy. i did pring all the assys out and ref the one you show. Is item 6 moslikely the problem piece. do the springs in item 6 force the shaft out during normal operation then the trigger compresse the internal springs allowing the 2 halvs of item 6 to interlock spinning the 2nd wheel?

how do you think the local outdoor shop would feel if i asked to see a brand new #6 assy to compare it to mine? Would they even have one in stock? Im think that would be a good spot to try. I dont want to re-assemble if the internal gears are worn.

Is there a rework procedure for those. they look to be riveted together and im assuming the replacement has to be purchased as a complete unit.

thanks agian

bwoz wrote:
The chances of gear wear on the inside of this differential are next to zero. There is a flat-wire spring holding the sun gears apart. These sun gear have dog clutch faces and will lock out the differential (lock to each other) when the plastic cams engage the tube that slides over the axle. If you have it apart, make sure the sun gears are still spring loaded (opposing) and that the sun gears can turn opposite each other when the sun gears are not engaged with each other (use the axles to slide into the spline to do this). Note also, this differential is not symmetrical. Only the sun gear on one side can shift. Make sure that 3 of the 37 teeth have a dot on them, and that these dots face the interior of the transmission. Make sure the splines on the axles are clean and greased. Make sure the clear tube over the axle slides freely and that it allows the sun gear to retract when the cams are disengaged. Check the adjustment for the trigger cable in the manual to make sure the cams are not over-actuated. Let me know what you find...

PK

Thanks PK.

When i had the Bad differential out i did inspect the flat springs under a scope at work. they all looked rusted out and as you indicae they had no spring to them. I was able to confirm that one geer did spin opposite when i pulled the two sun gears apart. I think the problem was when they got pushed back together nothing was pushint them apart.

I removed the assembly from My newer machine and the spring force was pretty good and after a cleaning to make sure the tube slid well all seems to work fine on my unit.

The one that i got in the raffle well that one is shot. I was able though to get the sales slip and it is currently in the shop under a warantee repair no charge. they're even replacing the scraper bar. Not sure how he prev. owner blew through both those parts in 3 seasons?

Anyway thanks for the help and info on correct orientation. im going to make sure i put mine back in correctly.

Oh BTW can you replace the springs in the differential? Its seems as simple as grinding off the rivits, punching out the dowels and matching a specific smaller spring force exerted by the plastic slide. Just thinking down the road if it happens again out of warantee.

thanks again