A7 Primary Chain Case

[vwphillips]

I have been attemption to remove the primary chain case for my A7 SS

First problem

There is no chain adjuster screw as shown in http://www.bsawiki.co.uk/index.php?title=Chapter10
or prain plug as discribed in the Haynes Manual.
As there does not appear to be a level plug how to I establise the correct level for what I believe should be 1/4 pint?

Second Problem

As I removed the screws oil drained from the bottom of the case oil drained from the bottom of the case
This oil was red, I expected brown engine oil(SAE 40)
Can any onr guess what the red oil may be?

Third and Major Problem

One(the third from the front bottom) allen screw will not come out, the key rotates
some of the other screws were very tight but released with an extention on the key

I have ordered a new set of allen keys in the hope that they will catch and undo the screw
but if not Iwill need to drill out the SS head unless there are any other suggestions?

I am fastly betting to regret buying this recently restored machine.

[stu.andrews]

  Problem 1           Measure out a quarter of a pint & add via the top screw plug in the chaincase
  Problem 2           ATF fluid has been added to your chaincase. This is fine as it will cause less clutch slip. It also has the advantage of knowing where the oil drips on the road are coming from!  Engine oil-                            blackish. ATF- red. Gear Oil- golden with a sickly smell.
  Problem 3           The screw will probably need drilling out & a helicoil insert fitted. Most engineering shops will be able to do it.

[Greybeard]

As there does not appear to be a level plug how to I establise the correct level for what I believe should be 1/4 pint?

On my 1955 plunger A10 the second or third screw from the front of the chaincase, (at the bottom of course) serves as a level indicator. There is a cut-out on the inside of the outer case so that oil can reach the screw hole when the screw is removed. Or just use a measuring jug.

[chaterlea25]

Hi Vw
The wiki link is for the early rigid and plunger models
HTH
John

[RichardL]

Before committing to drilling out the allen screw, I think I would try a different approach. Find a cheap  easy-out  that is larger in diameter near the top than the allen screw measures across the points. Break it off where its diameter will just clear the flats of the allen screw and turn counter clockwise. With luck, the easy-out will take a firm bite in the screw. I think the easy-out is unlikely to break off in the screw before the hex strips further, so, if it doesn't work, you shouldn't need to worry about trying to remove the screw with a broken off easy-out in it.

Richard L.


Edited due to a lot of thumb-typing errors.

[a10 gf]

The level screws? http://www.a7a10.net/BSA/manual54/im20-21.jpg

Complete manuals are here > http://www.a7a10.net/forum/index.php?topic=454.0

[muskrat]

Yes I'd go with Richards method first and as an extra rig it up to an impact driver. Failing that just drill the head of with a 17/64" drill. Once the other screws are out the cover can be removed leaving the shank of the screw proud to get vice grips on.
Cheers

[Greybeard]

I used penetrating fluid, heat, (carefully applied from a plumbers torch) and an impact driver when struggling to get the screws out of my chaincase. I still had the original slot headed screws; it should be easier to remove socket head screws but on the other hand they are likely to be nipped up tighter when fitting. There is really no need for the chaincase screws to be super tight.

When I was a teenager I put allen screws in the cases of my Ariel Huntmaster because I thought it was a cool thing to do, (and it was a modification that I could afford). I expect I tightened them up as only a 16 year old can do!

[bsa-bill]

I expect I tightened them up as only a 16 year old can do!

Know what you mean

Slotted screw look good until removed / returned a couple of times 

[unclerob]

A method I've found that often works is to take a slightly larger hex key, cut the longer leg off and carefully grind a shallow taper on all 6 sides so it only just fits into one of the good bolts, then hammer it hard into the damaged one. And undo with the appropriate sized spanner.....hopefully!

[vwphillips]

Thank you for the advice and the info on the level and drain screws

I have ordered a set of easyouts

the new set of allen keys and easyouts are due Tuesday/Wednesday

[RichardL]

I like both Musky's and Unclerob's suggestions as much as my own. A good set of easy-outs and
allen keys are worthwhile to have, so, no waste there. I think I just assumed most folks here are like me, with decades of accumulated loose tools like drill bits, allen keys and a smattering of easy-outs. Maybe I should have emphasized CHEAP easy-out when suggesting breaking it off. The easy-out method's only chance of working is if the tip just barely enters the screw, which will be iffy with one that is not modified. Then, still no guarantee. Maybe I should have added something like, "let's see what others have to say," so we had a little discussion before the money started to flow.

The fact is, the screw is cheap and it's dead anyway, so Musky's approach may be the quickest and would have been the cheapest way to go. Now, it's really going to be interesting to hear what worked.

Richard L.

[Briz]

Yeah; just drill the bugger off.
If you have a reversable drill, a LH drill bit is even better, half the time it'll grab & unscrew the offending bolt anyway.
LH bits are easy to get on ebay.

[vwphillips]

I am glad to say that the screw came out with the new allen keys

I will not be using it again

Thank you all for your suggestions