Author Topic: In gear but no go (Read 686 times)

Terry · « **on:** September 06, 2018, 07:15:13 PM »

Hi,

I have a somewhat interesting problem in a Moke that I have yet to find out the cause.

Initially the description of the problem from the owner was 'something went bang and then I had no movement' and I looked at it a few years ago when it happened and decided the problem must have been in the gearbox or diff, probably a blown pinion.

Fast forward to now, the owner(MokeMark on here in the early days) wants me to fix it so I picked it up the other day and while just rolling it along the trailer to unload it, suddenly it started turning over the engine as it had been left in gear.

More playing with it today, I had to get the engine running again first, I find I can roll the Moke in gear and it will turn over the engine, but without touching anything else I can then turn the key and start the engine with the Moke still in gear and it sits there happily not going anywhere.

Terry

Halfpint · « **Reply #1 on:** September 06, 2018, 09:13:48 PM »

That doesnt make sense Terry, unless the clutch is disengaging or slipping when the engine is turning over or something.
The gears are quite positive and the clutch is in between.
If you truly have an engaged drive train, it has to be in primary gear/ clutch area, I think...... Interesting

HP

Pete Power · « **Reply #2 on:** September 07, 2018, 08:50:54 AM »

moemoke · « **Reply #3 on:** September 07, 2018, 01:30:09 PM »

something in the drive train but I wouldn't be standing in front or behind while it is running in gear

Could it be a CV or driveshaft that's broken in a certain way and when you push the moke
(the wheels driving the motor) it turns over but the motor wont drive the wheels.

Drakman · « **Reply #4 on:** September 07, 2018, 07:45:48 PM »

Flywheel bolt broken/ loose flywheel. No load it turns the engine, as soon as you supply load in the form of power from the engine the flywheel slips?

Terry · « **Reply #5 on:** September 11, 2018, 08:17:25 PM »

Hi,

and the winner is......no one.

I removed the wok and spring plate in the car the other day hoping to see something obvious but nothing. Today I took the engine out of the Moke and while draining the oil noticed there was quite a bit of metal on the plug and around the hole which was enough to make it trickle out.

So I went for the Diff first, removing the covers and housing and all good in there, so that knocked out PP and I for guessing right and Moe was already gone because the CV's were fine.

Got the flywheel off and the clutch plate was a little moist but not enough to cause any issues and the primary gear was also good so HP and Drakman miss out on the prize also.

Turning the primary gear one way it spun freely, but turned the other way it it would engage the gearbox so the problem was deeper inside so off with the transfer housing to find the problem....

The first motion input gear, the one below the idler, was freely moving along the shaft to the point of killing another transfer housing, the spigot bearing was pushed past the missing circlip and the locking nut was out the end of the thread, with the locking washer eventually found mangle in pieces inside around the sump plug. The was about 20-30% of the dog gears left on the shaft and slight more in the gear but the rest of the teeth were worn off which leads to the symptom of on gear one way and not the other.

In one direction the gear turns and by the natural shape of the helical gears it goes out to the nut and past the remaining teeth dog teeth on the shaft. Turned the other way the helical gears moves it in towards the gear box, engages with the last bit of the dogs molars and we are in gear again.

So with the engine running spins it out, rolling the car forward moves it in.

I took some pictures but only the first couple are good enough to show so I will have to get more tomorrow before I dismantle the things.

There should be a bit of shaft and circlip showing to the right of the spigot bearing and you can see the angle of the main input gear as its insides are chewed out and it should be hard to the left.

Terry

Halfpint · « **Reply #6 on:** September 11, 2018, 10:12:36 PM »

Well there you go, makes sense now.
HP

Pete Power · « **Reply #7 on:** September 12, 2018, 02:52:15 PM »

That was my next guess ....

DOH!!!

Terry · « **Reply #8 on:** September 12, 2018, 08:55:37 PM »

Hi,

well this is a problem that just keeps on giving.

I started to remove the first motion shaft and was inside the gearbox, popped out the Layshaft and extracted the gear and shaft out with the big bearing and found that I also had some of the main shaft stuck in the end of the 4th gear. Now this may explain the Bang the owner heard when things stopped going forward but if you look at how shining and polished looking the end of the shaft is it seems to me that the two pieces have been spinning against one another for sometime.

A picture of the failed 1st motion shaft alongside a good one, the failed one is on the right/top.

And the inside of the same piece with the broken shaft jammed in there.

And the internals with where there should be a bit more shaft sticking out the end.

Terry