New Bearings?

[tomking]

Does anyone know if new antifriction bearings are available to rebuild the Opel 4 speed? I havent taken them into the bearing house yet but wont be too surprised if they say NA. Thanks.

[biglefti]

Very few bearings are designed item specific. Most things are designed around an already existing bearing, so you should be able to locate the ones you want.

[GTJIM]

Most gearboxes use standard 6200 series metric bearings with an external circlip groove to locate them. They usually have a C3 'slackness' rating which tells you how 'loose' the bearings are to allow for expansion as they heat up to operating temperature.

The Opel box should have something like 6206 NR or 6207 NR size bearings, though heavy duty ones are also available with extra balls and a filling slot where they have been fed in between the race. The usual designation for this type is 206 NR or 207 NR and they are very worthwhile to increase the load capacity of the gearbox.

Just check the size of the existing bearings and see if they both have external circlip grooves. These standard gearbox bearings are readily available at most Bearing Supply shops - DON'T let them know they are for an Opel!

[tomking]

OK so the small needle bearing and both ball bearings are easily sourced. But my local bearing supplier cant seem to find that larger needle bearing with separate race. Anyone know where to get that short of buying a complete tranny rebuild kit? Does anyone have the specific bearing number for that? Or is that particular needle bearing made only for this tranny and therefore not available thru commercial suppliers? Thanks.

[GTJIM]

Your description is a bit cryptic ... I can only guess that the "small needle bearings" are the ones for the layshaft at each end of the cluster gear and "that larger needle bearing with separate race" is the bearing that fits on the end of the mainshaft, inside the input gear.

Loose needle rollers are available separately from bearing suppliers but the caged needle rollers on the mainshaft are probably Opel/Vauxhall/Early Vega specific as the Opel gearbox is a unique item and not a Borg-Warner clone.

The Opel part number is 720181 BEARING, main shaft - needle - frt (in main drive gear).

Unlike other parts in the list is does not have a Vega number so may not be used in Vega transmissions.

In times of desperation I have repaired gearboxes by replacing this type of needle roller with a bronze bush - but extended idling, out of gear, with the clutch engaged does cause rapid wear. Even tried hardened steel sleeves .. but same problem.

There is simply no real option but finding the genuine article - though you may be able to replace it with appropriately sized loose needles and some hardened steel washers from another gbox .....

NOTE: Both the countershaft (which the loose needles run on inside the cluster gear) and the tip of the mainshaft (which the caged needle bearings run on) are very prone to spalling and pitting of the contact surface in higher milage gearboxes ... which is another problem all in itself ...

The counter shaft has an Opel part number 3442445 and a Vega part number Vega 3442445 Both the same! So it may be worth asking at your local GM Chevrolet Dealer for Vega parts with both the caged needle bearing number and the counter shaft number.

The only other suppliers would be Vauxhall/Opel Dealers in Europe - Anthony Drosos in Greece may be an option or Opel Parts (on eBay) in Germany.

Good Luck! Though it may be easier to just get another whole used Opel gearbox locally, that is in better condition than yours .....

A visit to a gearbox repair shop may be another option ... with the old part in hand - then ask them if they have anything like it ...

[tomking]

Thanks Jim
Your description is a bit cryptic ... I can only guess that the "small needle bearings" are the ones for the layshaft at each end of the cluster gear and "that larger needle bearing with separate race" is the bearing that fits on the end of the mainshaft, inside the input gear.

My reference to the smaller bearing meant journal diamter. The smaller bearing goes on the end of the main shaft. It does have the larger rollers or needles and that bearing is readily available. Its the other needle bearing that must be specific to the gearbox and doesnt seem to be readily available. It is the larger of the two for journal diameter and yes it has tiny needle bearings in it. And the inner race for it will press off the journal. sometimes it will slip off the journal. Thanks again.

[nobody]

Give a call to Machine tool bearings in Chicago or MTBA on the web. I don't have thier phone number handy but every goofy bearing I've ever needed they have come up with and seals for just about anything. They also sell things that beat bearings, like the newer plastic polymer adhesives. Rhulon a and b and the Turcite. Sorry, I'm a lets let it run big R's junkie. Ask them about Kluberlube while your at it.