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B.S.F.
22nd March 2012, 12:26 PM
Is it advisable to replace a broken Distance Piece in the gearbox, 239706 or 571218 with a 2-piece D/P FRC 4076/4077 or does that create new problems?
Ever since I worked on my first L/R gearbox over40 years ago I've come across this problem.It seems to me that L/R never really tackled the issue ,apart from producing a "broken" (2-piece) sleeve.
Cheers W.

kowanyamakid
24th March 2012, 09:04 PM
Good question. All old series 2 boxes I have scavenged and dismantled have had either broken distance pieces or are forming annular cracks prior to failure.
I got my hands on a used Series 3 two part bush recently and asked the same questions. I decided to fit it into a Series 2 box and see how it went. The aft end of the bush is prevented from spinning by the locating pin in the mainshaft (same as the one part bush) but the forrard end appears to be left to spin on the shaft with the gear. I could find no documents that referred to this type of bush and wondered if I should locktite it to the shaft. I suppose its not going to break – its already broken:angel:
Anyway, I don’t know as the box is now sitting on the shelf as a spare and is yet to be tested.
But it is probably not too much to worry about as I refitted my present gearbox with a used (but genuine I reckon) 1 part distance piece , dug out of a swamp at Humpty Doo– the “strengthened” version as per the annular groove – and kept an eye out for gold in the drain plug. That was 85,000 miles ago and its apparently still OK.
If the two part distance piece solves the problem, why do they still sell the one part? Some of the after market 1 piece distance pieces I’ve bought look quite dodgy.
Cheers

1964 GS109

wrinklearthur
24th March 2012, 09:34 PM
I have had my share of 'finds' when stripping a box that had been jumping out of gear.
For years I had dutifully used EP90 in both the transfer and the gearbox and I used to be disappointed with the lack of service the gearboxes gave after their rebuilds.
Now I am told that EP90 should not be used in the gearbox, instead only a 50 grade straight mineral oil should be used.
So much for seeking advice from an oil company representative at the time.
.

B.S.F.
24th March 2012, 09:34 PM
"If the two part distance piece solves the problem, why do they still sell the one part?"

That's exactly why I posted this question. I've got a used one with groove, which I shall use.Thank you for your reply.

wrinklearthur
24th March 2012, 10:44 PM
"If the two part distance piece solves the problem, why do they still sell the one part?" That's exactly why I posted this question. I've got a used one with groove, which I shall use.Thank you for your reply.

I haven't had any experience with the two part distance piece and I am interested in hearing from anyone about the service this modification gives.
.

fc110
25th March 2012, 08:37 AM
The aft end of the bush is prevented from spinning by the locating pin in the mainshaft (same as the one part bush) but the forrard end appears to be left to spin on the shaft with the gear.

For some time I have been drilling a small hole in the one piece bushes, in line with the annular groove inside the gears, the one that goes ALL the way round.

My theory is that if the bush breaks &/or spins on the shaft the oil will provide lubrication between bush & shaft. Unfortunately, I've never seen any rhyme or reason when the bush breaks, or for that matter I've never had a broken bush in GBs I've repaired.

Also I pulled the GB every year or so, if I hadn't had problems I knew they weren't far away.

I think drilling the hole in at least the 3rd gear part of the 2 piece would be essential. The bush is lubricated by the meshing gear forcing oil into the annular groove & then being distributed across the gear/bush by the spiral grooves. My idea is that a small amount of oil should be forced thru the bush hole to oil the bush/mainshaft area.