Author Topic: A10 rocker cover  (Read 7664 times)

0 Members and 1 Guest are viewing this topic.

Trev

  • Blue Star
  • **
  • Posts: 51
    • View Profile
A10 rocker cover
« on: 10 February, 2017, 16:26:12 »
Anybody know of a fool proof method of refitting the A10 rocker cover, and keeping the the pushrod location tool in place while doing so?

STAR TWIN

  • Royal Star
  • ***
  • Posts: 226
  • A7 A10 B31 WDB40
    • View Profile
    • Strange Sheep
Re: A10 rocker cover
« Reply #1 on: 10 February, 2017, 17:30:37 »
No. I have tried and failed more times than I can remember to fit the rocker box using the pushrod locating tool. Perhaps it's just me, but I invariable end up using screwdrivers or bits of bent wire to get the pushrods where they are supposed to be.

Dean Southall

  • Golden Flash
  • *****
  • Posts: 746
    • View Profile
Re: A10 rocker cover
« Reply #2 on: 10 February, 2017, 18:03:51 »
Makes cup of tea and settles back in armchair...this is going to be  a long session ;)

This is the worst job you have to do on a BSA, many a forum page has been devoted to it. If ever there was an aspect of motorcycle ownership that warranted a Support Group this is it.

I manage to hold the comb in position with one hand and drop the rocker box with the other. The withdraw the comb alond with half the gasket sealant to find the pushrods aren't enganged in the rocker cups anyway  GGGGRRRRRRRRRR.

Next time I am going to try a tip on another forum. Use elastic bands arond the rockers to hold them up then use a miiror, torch and wire hook to locate the rods. I always end up having to fiddle with a stick and mirror even when using the comb I'm going to junk the comb next time.

To check the pushrods are enganged and not just wedged between the rocker cups and the rckerbox wall I feel inside and make sure I can rotate the pushrods.
BSA: turning ordinary men into mechanics since 1910

JulianS

  • Empire Star
  • *****
  • Posts: 2631
  • A10
    • View Profile
Re: A10 rocker cover
« Reply #3 on: 10 February, 2017, 19:21:56 »
After 40 odd years trying this still presents me with a challenge.

It is probably the worst job to do on a preunit twin.

I dont think there is a foolproof way and I disgarded my pushrod comb years ago as it was quite useless.

The first issue is the limited space between the top frame tube and head can make it difficult to engage the four holding down studs into the holes in the head. This is worst with the alloy head 650s with long studs. The top inlet inspection cover stud was originally made with machined flats to ease its removal to increase the space.

Having overcome that obstacle I favour the elastic band method to hold the rockers in position. I put a bit of grease on the lower end of pushrods to hold them in the cam follower.

With an alloy head I cover the holes shown in the photo with a bit of tape, just incase the nut is dropped whilst fitting it, it can be a bit of a fiddle getting it out.

Fitting the sleeve nuts on the alloy head can also be a bit of a fiddle, getting the threads on the nut to catch on the stud.

 Having positioned the gasket and applied your chosen sealant, lower the box onto head and guide the pushrods into the rocker arms using your fingers. Sometimes the pushrods will be caught on the front edge of the inlet joint. Having fitted the pushrods, probably after several attempts, and avoiding force insert the four long bolts and gently tighten a bit and add the other bolt and the four nuts. You may need to rotate the engine to allow easy tightening.

Having finally tightened all the fasteners you can set the valve clearances.

If using thick modern gaskets, which might come in blue or orange or yellow materials, expect them to settle after a little use needing the fixings being retightened and clearances to be reset.

Keeping the oil in can also be a challenge but that is another tale.

ANDY HIGHAM

  • Royal Star
  • ***
  • Posts: 142
    • View Profile
Re: A10 rocker cover
« Reply #4 on: 10 February, 2017, 19:54:24 »
Somewhere there is a rocker box that I modified. A couple of holes were cut in the box top and tapped aluminium bushes welded in place. The pushrods could then be eased into place and after the rockerbox has been bolted down, plugs screwed into the bushes. I think I used 25mm conduit thread.

Trev

  • Blue Star
  • **
  • Posts: 51
    • View Profile
Re: A10 rocker cover
« Reply #5 on: 11 February, 2017, 10:59:02 »
Thanks for all your comments gents. As I feared it looks as there is no easy or simple solution. If I had maching skills I would investigate making some studs that were about 1/8" shorter to give just a little more room for manoeuvre.

CRAIG12

  • Guest
Re: A10 rocker cover
« Reply #6 on: 11 February, 2017, 11:29:47 »
comb works fine for me , you need to snap some of the teeth to suit position but that's all

TTJOHN

  • Golden Flash
  • *****
  • Posts: 543
    • View Profile
Re: A10 rocker cover
« Reply #7 on: 11 February, 2017, 11:50:43 »
Anybody know of a fool proof method of refitting the A10 rocker cover, and keeping the the pushrod location tool in place while doing so?

The best method I found was to use the comb but bend it in an S shape so that it fits flat on the top fin of the head then secure it with some thin mole grips, this holds everything in place and I find its pretty easy now, I hope your using one of my solid copper gasket sets, to stop the leaks.

Regards TTJohn

Trev

  • Blue Star
  • **
  • Posts: 51
    • View Profile
Re: A10 rocker cover
« Reply #8 on: 11 February, 2017, 12:21:51 »
Quote
I hope your using one of my solid copper gasket sets, to stop the leaks.
Indeed I am and it is due to the front nearside of the cover leaking that I have had to tackle this task. I also intend to use this (see image below) with the copper gaskets. This is what the product claims to be and to do. " An anaerobic sealer which means it only sets on the contact of metal and closure from air. If any is squeezed out it will not set and cause damage inside the engine. It stays liquid and dissolves into the surrounding liquid, unlike normal Rtv/Silicone sealer which will cure and cause damage from blockages". It is an exercise in 'belt and braces' I am sure that your copper gaskets are every bit as good as you claim they are, but I don't want to take any chances. I know that the rocker covers are notorious for leaking, and I really do not want to repeat this exercise any time soon. It really is a dreadfull concept.
« Last Edit: 11 February, 2017, 12:29:43 by Trev »