Mk 3ES outrigger plate problem

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Hi all, I'm in the process of reassembling the primary chain cases on my Mk3 ES after removing them to drop the engine far enough to pull out the rear isolastic. When I tighten up the outrigger it pushes the starter drive gear hard up against the chain tensioner plate cover to the extent that it won't turn. Before tightening there is a gap of around 16 thou between the back of drive gear (this is the one that houses the anti-backfire ball bearings) and the cover plate but that closes to zero when the outrigger is tightened up. I can't think of anything that I've done that may have caused this to happen as the starter turner OK before I started the job.

I pretensioned the AB unit to 50 ftlb and replaced the drive gear 06-4707 as the ball bearings had been cutting a bit of a track in there, but that's about the extent of it. I could put washers between the outrigger and the inner primary to stop it pushing the ES drive assembly on to the chain tensioner plate but I'm wary of messing with the resulting change in the stator position, being aware of the sensitivities of rotor/stator clearances. Alternatively I could cut a deeper seat where the starter drive shaft houses in the outrigger but I don't have the machine gear and it seems a bit drastic for a problem that sorta turned up out of the blue.

Any clues?
 
Having been there fairly recently, I was wondering along the same lines as Esme.

Mk 3ES outrigger plate problem

You can see in my pic how the thrust washer sits over the circlip.

My guess is that if either are on the other way, it would nip up tight when you tighten up the four bolts that attach the outrigger plate to the primary case.
 
Hi all, I'm in the process of reassembling the primary chain cases on my Mk3 ES after removing them to drop the engine far enough to pull out the rear isolastic. When I tighten up the outrigger it pushes the starter drive gear hard up against the chain tensioner plate cover to the extent that it won't turn. Before tightening there is a gap of around 16 thou between the back of drive gear (this is the one that houses the anti-backfire ball bearings) and the cover plate but that closes to zero when the outrigger is tightened up. I can't think of anything that I've done that may have caused this to happen as the starter turner OK before I started the job.

I pretensioned the AB unit to 50 ftlb and replaced the drive gear 06-4707 as the ball bearings had been cutting a bit of a track in there, but that's about the extent of it. I could put washers between the outrigger and the inner primary to stop it pushing the ES drive assembly on to the chain tensioner plate but I'm wary of messing with the resulting change in the stator position, being aware of the sensitivities of rotor/stator clearances. Alternatively I could cut a deeper seat where the starter drive shaft houses in the outrigger but I don't have the machine gear and it seems a bit drastic for a problem that sorta turned up out of the blue.

Any clues?
Having been there fairly recently, I was wondering along the same lines as Esme.

View attachment 7856

You can see in my pic how the thrust washer sits over the circlip.

My guess is that if either are on the other way, it would nip up tight when you tighten up the four bolts that attach the outrigger plate to the primary case.
 
Thanks @gtiller and @Esmerela, agreed a couple of photos could be helpful I should get around to tackling Photobucket. I've definitely got the thrust washers on the right way round and I've checked to make sure there is nothing in the recesses that might stop the circlips housing properly. If they were back to front I think they would effectively push the drive gear away from the cover plate rather than towards it (have I got that right? been pondering on this a little too long...). The only oddity I found was that the circlip on the threaded end of the drive shaft wasn't located as well as it could be and was sitting on a rough area in the groove making it protrude slightly but I've corrected that and buttoned it up since and it's made no difference.

Keen to get your thoughts on this theory however - the inner primary has evidence of a stitch job on a crack most likely due to the strain caused by incorrect positioning of the nut on the chain case steady stud. After reading a few posts on this forum I took care when I reassembled it make sure that wouldn't happen again by tightening up the nuts at the crankshaft end of the primary and then turning the nut on the chain case steady until it was snug on the back of the primary thereby in theory ensuring that the surfaces that the inner was being attached to were all in the same plane. I then gave it a dab of green loctite to keep it there.

So - apologies for the long-windedness - if I have potentially moved the inner primary outwards slightly with this adjustment perhaps it has had the effect of bringing the chain tensioner cover plate (which is effectively attached to the inner primary) closer to the starter drive gear (which is effectively attached through the long studs to the crankcase, albeit through the outrigger plate).

Or could I still be a bit dusty from NYE last night?
 
OK, that theory out the window. Loosened off the chain case steady on both sides so that the inner primary is only secured at the front end, buttoned up the outrigger and the starter drive gear still binds against the chain tensioner cover. Thinking that maybe the outrigger nuts have a very low torque setting and the nuts are secured by the tab washers but it seems weird. Appreciate any insights on this.
 
Mk 3ES outrigger plate problem

Bill,
This is the only picture I have with everything assembled. Does yours look the same? Is the tensioner pump body positioned correctly and tight against the inner primary case?
Pete
 
When I tighten up the outrigger it pushes the starter drive gear hard up against the chain tensioner plate cover to the extent that it won't turn. Before tightening there is a gap of around 16 thou between the back of drive gear (this is the one that houses the anti-backfire ball bearings) and the cover plate but that closes to zero when the outrigger is tightened up. I can't think of anything that I've done that may have caused this to happen as the starter turner OK before I started the job.

If it didn't do it "before" then the problem wouldn't seem to be anything to do with the actual outrigger.


The outrigger 'legs' locate against four substantial pillars cast into the inner primary case and once located it isn't going to move from the nuts being tightened unless the inner primary case moves with it.

Mk 3ES outrigger plate problem


Mk 3ES outrigger plate problem
 
Thanks @L.A.B. & @Deets55, agreed it doesn't make sense that the outrigger is the problem. I'm not really sure whether I'm making a problem where one doesn't exist though and would appreciate your thoughts and insights. Where this started from was on attaching the outrigger I noted the I could no longer turn the starter drive gear by hand whereas I was able to prior tightening it up. So it's made me question a) what the torque should be on the outrigger nuts (I note that it's 15ftlb for the stator nuts so logic tells me it would be the same or more for the outrigger), or b) is being unable to turn the drive gear by hand normal and the starter motor would manage it without difficulty. Although I started this project with trying to solve a screeching noise on starting as one of several objectives, the absence of any witness marks on the drive gear or the cover plate suggests that they haven't been fouling before. Just to make things a bit more mysterious the Mk3 ES workshop manual describes the reassembly of a Mk2A primary (there may be some technical notes to cover this somewhere on the world wide web but I haven't had any luck finding them), so it excludes the starter drive instructions. The biggest question for me is the torque of the outrigger nuts. Everything in your photos looks the same as mine. Thanks again for your help on this.
 
So it's made me question a) what the torque should be on the outrigger nuts (I note that it's 15ftlb for the stator nuts so logic tells me it would be the same or more for the outrigger),

The outrigger stud/nut torque (15 lbs.ft) is given in the manual, section C34,28. however, the page containing C34, 28-34 is missing from the online manual.



or b) is being unable to turn the drive gear by hand normal and the starter motor would manage it without difficulty.

I wouldn't say it was normal but I can't see how torquing the nuts would be likely to cause the problem Edit: if the outrigger is seated correctly in all four places.

Although I started this project with trying to solve a screeching noise on starting as one of several objectives, the absence of any witness marks on the drive gear or the cover plate suggests that they haven't been fouling before.

Which once again makes me think the problem lies elsewhere, either with the anti-backfire drive gear or the tensioner assembly.



Just to make things a bit more mysterious the Mk3 ES workshop manual describes the reassembly of a Mk2A primary (there may be some technical notes to cover this somewhere on the world wide web but I haven't had any luck finding them), so it excludes the starter drive instructions.



The Mk3 manual describes the reassembly of the Mk3 primary and starter motor drive in some detail in section C (except for the previously mentioned missing online manual page) so I don't understand that at all?

Mk3 manual:
http://britmoto.com/manuals/Manuals/850_man.pdf

https://www.oldbritts.com/e_start_gears.html
https://www.oldbritts.com/e_start_backfire.html
 
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The outrigger stud/nut torque (15 lbs.ft) is given in the manual, section C34,28. however, the page containing C34, 28-34 is missing from the online manual.


That explains why I couldn't fine details about the outrigger - I have been using an earlier online Mk3 manual that also excludes C34,28. However - importantly - I now have the torque settings for the outrigger (thanks mate).



I wouldn't say it was normal but I can't see how torquing the nuts would be likely to cause the problem Edit: if the outrigger is seated correctly in all four places.

It's got me stumped. The outrigger is sitting nicely on the legs but the moment I tighten the nuts closest to the starter drive if fouls the cover plate. With just the front two nuts tightened the drive can easily be turned manually.


Which once again makes me think the problem lies elsewhere, either with the anti-backfire drive gear or the tensioner assembly.

I'm pretty confident that I have the assembly right for those two (with thanks to OldBritts) but I might pull them down and start again to be sure. The paper gasket was missing from the chain tensioner but apart from that I couldn't see anything sinister although there's some evidence of dodginess elsewhere by the previous owner. Could it be that there is some warping of the inner that happened when it was stitched? I've checked the top edge of the inner where the stitch took place and is seems to be nicely in line but you may have experienced something along those lines before perhaps? Seems a bit far fetched but I'm running out of ideas on this one. I'm wondering if I might just get the starter drive shaft seat in the outrigger machined down .016" (that's the gap between the gear and the plate before torquing up) and put it down to experience and the dark mysteries of Norton Villiers...




The Mk3 manual describes the reassembly of the Mk3 primary and starter motor drive in some detail in section C (except for the previously mentioned missing online manual page) so I don't understand that at all?

Mk3 manual:
http://britmoto.com/manuals/Manuals/850_man.pdf

https://www.oldbritts.com/e_start_gears.html
https://www.oldbritts.com/e_start_backfire.html


I've downloaded the Britmoto manual, it has more detail than the one I'm using so once again thank you for that. Yes it has starter reassembly details but it was the reference to the outrigger I was missing. Thank you again for your wisdom on this.
 
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The paper gasket was missing from the chain tensioner but apart from that I couldn't see anything sinister

Did you fit the missing tensioner gasket as that would reduce the clearance between the plate and the gear although it shouldn't lock up the gear? If you have fitted the gasket I suggest you remove it and see if that makes a difference. If it does then use a thin smear of jointing compound instead.


although there's some evidence of dodginess elsewhere by the previous owner. Could it be that there is some warping of the inner that happened when it was stitched? I've checked the top edge of the inner where the stitch took place and is seems to be nicely in line but you may have experienced something along those lines before perhaps?

It's a possibility but doesn't alter the fact that the drive was apparently OK beforehand.


Seems a bit far fetched but I'm running out of ideas on this one. I'm wondering if I might just get the starter drive shaft seat in the outrigger machined down .016" (that's the gap between the gear and the plate before torquing up) and put it down to experience and the dark mysteries of Norton Villiers...


I suggest you tighten the outrigger without the anti-backfire shaft assembly and measure the distance between the outrigger seat and the case.
 
Hi Bill

Are both of the primary tensioner plungers moving freely? If you are confident that you have the starter shaft assembled correctly, perhaps the primary tensioner is not fitting back against the inner case properly ?
 
That explains why I couldn't fine details about the outrigger - I have been using an earlier online Mk3 manual that also excludes C34,28. However - importantly - I now have the torque settings for the outrigger (thanks mate).





It's got me stumped. The outrigger is sitting nicely on the legs but the moment I tighten the nuts closest to the starter drive if fouls the cover plate. With just the front two nuts tightened the drive can easily be turned manually.




I'm pretty confident that I have the assembly right for those two (with thanks to OldBritts) but I might pull them down and start again to be sure.

Yep, pull it apart and start over. As has been stated, if it DIDN'T exhibit this before you disassembled it and now it does, something went awry in the re-assembly. I suspect that if you pull it completely apart and start over there will be an "AHA!" moment. ;)
 
Thanks all for your thoughts and insights. I've come away from your collective wisdom with a plan. Off the back of @L.A.B. suggestion I'll reassemble the outrigger without the starter drive and take some measurements. That will give some concrete data to guide me. The paper gasket is whisper thin so I don't think that's the issue (I'm looking for .016" - the distance between the back of the drive gear and the cover plate pre-tightening) HOWEVER - why was that omitted previously? I'm sensing I've inherited an issue rather than making one. I also vaguely recall the outrigger assembly nuts being less tight than expected, and similarly the studs. I wish I followed that up at the time but I didn't. Lesson for another time. The chain tensioner assembly has got to be highly suspect so I'll check that too. I've had it off and on a few times now but let's see. The primary tensioners are moving freely. As much as it's painful I'll rebuild the starter drive - getting that 50ftlb slip using my piddly vice is tricky. Off to the cricket for the next two days but I'll report back early next week . Thanks again to all.
 
The paper gasket is whisper thin so I don't think that's the issue (I'm looking for .016" - the distance between the back of the drive gear and the cover plate pre-tightening) HOWEVER - why was that omitted previously?

Possibly because it's not on the parts book diagram? Only included at the end of the list page as "Not Illustrated".
http://britmoto.com/manuals/Manuals/8503e_pt.pdf
 
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Pulled the primary/starter drive/chain tensioner down again as recommended and made some discoveries. First up the alternator studs were quite loose so I attempted to tighten them to 15ftlbs but lost my nerve when they started to get that unhealthy thread-stressed feeling, so I cleaned them up, doused them in Loctite medium and tensioned them to what I estimate to be around 10ftlbs (I figure they'd been half of that prior, if that). Checked the chain tensioner assembly and its seating on the inner primary case - all good. Checked the starter drive making sure the thrust washers were correctly positioned and that the circlips on the drive shaft were seating nicely in the recesses - all good. Aha! moment arrived when I realised that it wasn't the drive gear binding on the chain tensioner cover plate at all (hence the absence of witness marks) but the 'E' circlip (06.4754) on the drive shaft fouling the outrigger (plenty of witness marks there - could this be the source of the screeching that I was hearing when using the ES?). This took the primary tensioner assembly off the suspect list. I then removed the circlip and reassembled the whole thing and voila! - starter gear turned effortlessly. The end of the drive shaft was visibly poking through the outrigger further than before which then raised the question - given that I still haven't discovered what's caused the problem do I just choose one of the following solutions a) leave the circlip off and rely on Loctite and the peened flange on the drive shaft nut (06.4745) to hold everything in place, but risking any endplay bringing the threaded section of the drive shaft in contact with the outrigger, or b) mill the seat in the outrigger 0.035" deeper, being the thickness of the circlip, or c) shim between the outrigger and the inner primary 0.35".
 
I am having similar problems, and the latest cause I can see is that the outrigger palate is a little warped. when its loose, everything turns, but tighten up and the whole think binds. Especially the nut under the backfire overload shaft boss. loosen it, everything is fine. nip it up and no move. I think the warpage is putting a side load on the backfire shaft into the outrigger.
 
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