Lots of bronze in my primary case oil

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Yellow_Cad

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On my 73 850, I disassembled the clutch (bronze plates) to clean out oil contamination and refilled (5 oz.) my primary case with ATF. Now three months and a few hundred miles later I was having the same problem of clutch dragging. When I took apart the primary case, I was surprised at the amount of bronze particles in the ATF. Maybe it is like a spill and not near as much as it looked like. Is this normal with bronze plates? Are the bronze plates better or not as good as the other type of clutch plates?
 
The ATF has detergants that would have cleaned off the bronze particles that were stuck to the insides. Did you use type F ATF?
 
Your sleeve gear bush isn't spining and wearing away on the main shaft circlip is it :?:
 
I gotta believe that the bronze is coming from the bronze clutch plates.

As to the ATF, I am using GM type because I had some on hand. I just can't imagine that the F type is so much better even though I have heard that.
 
Yellow_Cad said:
I gotta believe that the bronze is coming from the bronze clutch plates.
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I think splatt is probably right.

The sleeve gear bushes can occasionally work their way out of position and wear against the circlip.
It was a known problem, and late models had a wire circlip inside the sleeve gear to stop the bushes from moving out of position, very late models had two circlips, - one at each end.
 
Could you please identify the bushing with a part number or something so I can understand exactly what part you are referring to? What is the best remedy for this situation?
 
Yellow_Cad said:
Could you please identify the bushing with a part number or something so I can understand exactly what part you are referring to? What is the best remedy for this situation?
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2x items [17]: http://www.oldbritts.com/1973_g7.html

2x part 04-0062 : http://www.oldbritts.com/nor_comm_73_7.html


Note the bush retaining circlips at each end of the later MkIII sleeve gear [20]: http://www.oldbritts.com/1975_g6.html

I believe the bushes can be Loctited in place, - unless somebody else knows of a better method?
 
The bushings you note seem to be deep in the gear box, so would that mean that any brass that ended up in the ATF in the primary case would need to go through the clutch to get there? If so, the clutch really didn't look like all this had gone through it.
 
Yellow_Cad said:
The bushings you note seem to be deep in the gear box, so would that mean that any brass that ended up in the ATF in the primary case would need to go through the clutch to get there? If so, the clutch really didn't look like all this had gone through it.
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Any bronze swarf would probably wash away from the rear of the clutch?
And those bushes are inside the sleeve gear, which places the outer one right behind the clutch assembly, so aren't deep inside the gearbox.

The UK Norton Commando Service notes say this about the subject,

quote:

".....Sometimes the bush moves outwards and gradually mills itself away on the sharp edges of the circlip which locates the clutch......Often the first sign of sleeve gear bushes going is striking "gold" in gearbox or primary drive oil....."

According to the service notes new bushes should be Loctited in position and a cut-down clutch location shim (part 060894 or 060895) can be placed between the bush and clutch circlip.
 
Yellow_Cad . Had the same problem with my MKlll . I tossed the bronze plates and installed " Surflex" friction plates. Problem resolved. You will need to add an extra steel plate to get the correct stack height of the clutch . I also use tranny fluid in the primary.
 
Ron has made a good call IMO but be aware there are two kinds available. One has a steel core and the other an aluminum core. Some seem to use the later with no problems but I have found the steel cored one's to be much better and just a little harder to find.
 
I do have a spare used clutch basket with plates that have pads. Is this what I need or is it some type of aftermarket clutch plate that I need? If I can use the one I have, should I just use Brake Kleen to clean the pads and be sure to get the correct stack height? Now I see on the Old Britts site there is a piece that describes the bronze plates only going 500 miles between cleanings and that is about how mine was. Apparently, that person went to the Barrett type plates and did not need to service near as often.
 
Never had a problem with the bronze plates but I don't use ATF either. (Still going by the book and using motor oil.)
 
I use atf and bronze plates with no problems,Ido change the oil often and when Ido you can see bronze powder in it but not particles,do you have to adjust it to stop it draging,ie something wearing out,clutch push rod?.Personly I think atf is is a good choice.
 
Yellow_Cad

Surflex is just the brand name and i bought the plates from Mike at Walridge Motors , London Ontario, Canada. It sounds like you have some factory plates on hand already so why not try them and if they work either run it as is or treat yourself to a new set.

Good Luck
 
I guess I never have heard definitively which type of clutch plate, bronze or fiber pad type, is superior. It appears now that the fiber pad type is superior but not by an awful lot and apparently some people do just fine with the bronze plates.
 
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