early vs. late Ross steering gear parts

[RimfireJim]

I opened up my steering box this morning and looked at the bad news of a worn pin on the sector shaft and a chunk of the cam (worm) broken off. These, plus a worn ball on the end of the pitman arm means I need to replace all the major components except the housing Plus bearings and seals, of course. As I study the details for replacement parts, questions arise:

My M38 is S/N 55xxx, well after the 31377 transition from "early" to "late" Ross gear described in Ryan's book and in the ORD 9, yet I have an early housing per the pictures in the book (not reinforced around the fill plug, recessed numbers). Maybe a field replacement? Who knows . . .

The TM9-1804B Power train, body and frame manual mentions early and late versions of the horn button assembly, but doesn't say anything about the gear parts being different. The ORD 9 clearly lists different P/Ns for early and late (S/N 31377) versions of the steering shaft, the sector shaft, the pitman arm, and the steering jacket (plus a seal and gasket), but not for the housing. This would imply that the meshing parts would need to all be either early or late, but not mixed, but the housing type doesn't matter. Is that correct? I haven't found any information about what is different between early and late parts. And what would be different about the steering jacket that would matter?

In my search among the usual vendors, all the part numbers I see listed match the post-31377 ones in the ORD 9. Would they (cam, sector, pitman) all work together in my pre-31377 housing?

Also, one vendor list the sector shaft as P/N 804533, which in the ORD 9 is "LEVERSHAFT, steering gear, assy (post-31377)", which as best as I can figure out is the "SHAFT, arm, w/LEVER" WO-804534 listed two pages later plus the nut and washer that secures the pitman arm. Sound right?

One more: anyone have a complete used steering gear in decent condition they want to sell? Will be posting in Wanted forum, too.

Jim

[wesk]

I think the housing change was similar to the Willys deal where they update the blueprint but do not change the casting or part number.

I believe you should keep moving parts that move against each other matched by late or early.

It's been awhile since I rebuilt one.

[RimfireJim]

I think the housing change was similar to the Willys deal where they update the blueprint but do not change the casting or part number.

That makes sense if it is a running change and the part is forward and backward compatible in all assemblies. That's the way I do it in my work, changing only the revision letter of the part documentation, not the part number. That way bills of material and parts lists do not have to be updated when the change has no ramification. I can see how the reinforcing around the fill plug would be this type of change. Using this logic, early/late housing makes no difference.

I believe you should keep moving parts that move against each other matched by late or early.

Seems like a smart move. Using the converse of the above logic, part numbers would have been changed if they weren't backward compatible.

I think I may have figured out the early/late steering jacket situation: scanning through the ORD 9, I found "COVER, jacket oil hole (used on vehicles through serial No. 31377)", item R in Fig. 14-2. Looks like the early jacket needs this cover, and the late jacket doesn't. I don't have a jacket oil hole cover, and I also have a seal in the upper column (GG in Fig 14-3, which is used only after 31377), so it looks like I have a late jacket/column on an early housing.

Also, no gasket on the upper housing cover (a la early). There is an early and a later version of the upper housing cover; suspect I have an early. Whether the moving parts I have to replace are early or late is probably moot, since they are all shot and will be replaced en mass, but if that wasn't the case, seems like it could be tricky getting the right versions!

Jim

[artificer]

Be careful....I recently bought a Crown sector shaft & pitman arm which did not even fit together properly.
The sector shaft spline was actually not finished in the manufacturing process & not cut deep enough for the arm to fit on.

Crown could not have given a rats, the dealer indicated he would make good but with return postage @ $38 I dropped the new part in the bin & bought a Wess? Spain [Oxi Drama] which worked fine.

Mine was not an isolated incident Crown have some bad parts out there.

[RimfireJim]

Exactly why I'd rather find original parts in decent condition rather than dealing with "precision" repops. By "Oxi Drama", do you mean "Omix-ADA"?
Jim

[artificer]

By "Oxi Drama", do you mean "Omix-ADA"?
Jim

You hit it in one!