Main drive spacer

[StueyC]

When reassembling my 4 speed gearbox I noticed there is no notch or cutaway in the main drive gear spacer to accept the little "L" shaped key that comes with the rebuild kit. Is it essential that the spacer is keyed to the spline of the drive shaft? Obviously my gearbox was operating without it previously so I'm curious why the key is required.

StueyC.

[steinauge]

Did you get a late style (79-86) spacer by chance? They dont have the notch.

[StueyC]

Hi Steinauge, I've used the original spacer. The gearbox is marked MotorFactory so I suspect it is an aftermarket item. Would the aftermarket gearboxes be manufactured with all updates as per later model units? What was the use of the little key originally if it was dropped for the later models?

StueyC

[Bosheff]

The -37 was the only MDG spacer to have the notch in it. This spacer was used til mid 77. At that time the MDG spacer, the bearing race, as well as the 44 loose rollers were replaced with the newer caged bearing set up. Yes it is needed to correctly complete the assembly I've been told. Without the key your talkin bout, the spacer will not spin when the MDG spins. Install the key with long end engaged in one of the MDG spline recesses, and the short end into the MDG spacer. I ain't zackley sure why the spacer needs to spin. Maybe to adequately keep the seal from leakin, or to assist the 44 loose rollers in spinnin on the MDG. Anyone know fer sure....bosheff

[Bosheff]

If yer runnin an aftermarket tranny built to work for a 64 and earlier application, it was probably manufactured to accept the caged roller bearing setup. I'm guessin for that reason, it's probably got a different MDG spacer in it. The spacer registers the tranny sprocket so that it lines up with the rear sprocket....bosheff

[StueyC]

Hi Bosheff, my gearbox has a caged bearing for the main drive gear and a spacer without a notch for the key so I can only assume they manufactured these boxes to later model gearbox spec's that run without the key. I reassembled it without the key and fitted a new seal before starting to think whether I've done the right thing.

Will I be OK leaving it as I've assembled it?

StueyC

[Bosheff]

I don't see any reason why it shouldn't work. Why exactly did you have it apart to begin with?....bosheff

[StueyC]

Thanks for the reassurance Bosheff. I stripped the box to bead blast a poorly applied coat of crinkle black paint from a previous owner and I needed to replace the selector gear.

StueyC

[Bosheff]

If it worked satisfactorily before you pulled it down, and it was reassembled properly, it should work fine. Just out of curiosity, what is the selector gear?....bosheff

[StueyC]

The gear (33960-36A) that positions at the end of the shift cam in the ratchet lid. It had two teeth broken off.

StueyC

[Panacea]

I would sure expect the chain sprocket would keep the spacer spinning with the MDG when tightened securely, I see no reason for the key...but use it anyway. Mike

[StueyC]

Thanks Mike. I was just thinking that when looking at the parts drawing.

StueyC

Don't have any advise for the kickstart question I just posted do ya?

[steinauge]

If you leave the key out of the loose roller MDG spacer it will leak oil-at least all of them I ever left out leaked promptly and stopped when I put the key in.

[StueyC]

Hi Steinauge, my gearbox has the caged type main drive gear bearing so it appears from previous replies that I should be OK without the key?

StueyC

[steinauge]

That type bearing did not use the key,Only the loose bearing.