A65 Lightning project......

[JulianS]

It is a metal case oil seal rather than a Dowty washer.

It needs to be in good condition. I would, if it was my engine, change it whilst you have it apart.

[geraldhattrick75]

Thanks Julian- duly removed. Any idea where I might obtain one.... er, please?

[geraldhattrick75]

Just saw this on SRM's site, which shows it perfectly:   

[geraldhattrick75]

I've measured the old oil seal and have found a replacement on e-bay which I have ordered. (8x 16x 7)

I daren't think what sort of damage I might have caused if you hadn't put me right Julian... Many thanks.

And likewise to everyone else who has steered me thus far........ THANKS...

Dave

[geraldhattrick75]

Timing side rebuilt- complete with 'o'- ring and new 'nib' oil seal.
https://www.ebay.co.uk/itm/8x16x7mm-R23-NBR-Nitrile-Rubber-Rotary-Shaft-Oil-Seal-Lip-Seal/273757689632?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649

It doesn't look much like the one portrayed mind, being a bit of a stubby seal.

Thanks again for explaining things to me Julian.

[geraldhattrick75]

I've just bought two sets of +20 piston rings, so I should be working my way up the engine shortly. Thanks again for all your help on the bottom end.

I've also bought one of these cylinder honing tools to do a bit of 'glaze busting'... https://www.amazon.co.uk/gp/product/B001LQQS0S/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1

Is there anything to be careful of when using it please? (I know it has to be kept very lubricated and slow-ish speed.... but that's about all...)

Thanks,
Dave

[chaz]

Figure of eight cross hatching is what you want. In other words a long sweep not close hatching. Not too rough, if the stones fitted are too coarse some Emery cloth over them helps. I usually finish off with dry Emery a quick in and out. You might find getting the stroke difficult, either coming out at the top or bottom. Then a clean out with petrol soaked rag to take the abrasive away, then a good oiling with new engine oil to finish off.

[geraldhattrick75]

Thanks Chaz- very helpful mate.
Dave

[geraldhattrick75]

Er, I know that my progress is slow but it is kinda based on cash availability.

However, Christmas has been and my good family have thrown a couple of bob my way so I can start to make a bit more progress.

I have put new rings on the pistons and honed the, newly painted, barrels and will be ready to insert the former into the latter once my recently ordered 'ring clamps' arrive. (Tuesday the 7th, hopefully)

I have read the appropriate (engine rebuild) section of the Haynes manual but can find no reference to inserting the cam followers. Neither does the official BSA workshop manual seem to mention them. (my lack of observational skills is well known in our household, so it's probably down to that)

So I'm assuming that before I insert pistons into t'barrels, and after I have fitted the base gasket, I just wedge (with grease?) the cam followers into the appropriate holes at the base of the cylinders then, being careful not to dislodge them, feed pistons into the barrel and bolt it all back up, after removing the ring clamps- obviously.

Is that about right and is there anything in particular I ought to be aware of when refitting the barrels?

Thanks,
Dave.

Oh, and more importantly, Happy new year to you good folk.

[JulianS]

The followers are retained by circlips at the upper end. There is a machined groove just below the ball for the pushrod.

[Bess]

Hi,
    Here is a tool for fitting the clips:

https://www.ebay.co.uk/itm/BSA-A50-A65-CIRCLIP-TOOL/392293292812?hash=item5b56809b0c:g:24wAAOSwMnZc0vkQ

Best wishes...

[geraldhattrick75]

Well that's kinda interesting, and answers the question of why the followers all clattered into the crank when I first lifted the barrels..... (no problem on this project as I've completely stripped, washed, cleaned and blown the cases..... Might be a bit miffed if I was only stripping it for a rebore)

No circlips. (Maybe that's how the factory fitted the followers eh ?)

I'll look at obtaining some.

Again thanks for your invaluable help.

Regards,
Dave.

[chaz]

My two had circlips, very thin so really wouldn't take much bashing. Have you got a comb for the push rods.

[Bess]

Hi,
    Its highly likely the factory did fit them. They are a pain to remove and fit, I have never found any on the bikes I have opened and I have never put them back. I do as you suggested fit them with assembly grease, I always forget and mine fall into the crankcase as yours did  , I now have a extended grabber to get them out  .

As you have the barrels off it may be worth checking the 2 rear cylinder head bolts. If they are 5/16" diameter BSA recommended they are changed to 3/8" by modifying the barrel and head. Service sheet 149, Dec 1966 outlines the procedure. Its worth doing my last two builds leaked, last month I had one modified for £40 + vat (hours labour I guess).

Also service sheet 282, Sept 1970 recommends the cylinder head bolts and nuts have steel washers, 0.75" OD, 0.38 ID with a thickness of 0.092 to improve sealing of the cylinder head joint.

Best wishes...

[geraldhattrick75]

My two had circlips, very thin so really wouldn't take much bashing. Have you got a comb for the push rods.

I've ordered some 8mm jobbies off a circlip supplier.... (for £1.35 I thought it might be worth a look at.... They don't take any load do they, just retainers....?)

No comb for the push rods.
Are they as tricky as the A10 Super Rocket- which I found to be er, a tad tricky?...... (Euphemism for 'a total pain'...)

As you have the barrels off it may be worth checking the 2 rear cylinder head bolts. If they are 5/16" diameter BSA recommended they are changed to 3/8"

Just checked em on my cheapo digital caliper- 0.372 = 3/8... ish. (so thank you to the geezers' at the factory... And to you Bess for the info.)

On the whole though, I may just leave the followers without the circlips- depending how tricky they are to fit and how suitable/ safe they might be...... (I too have an extended grabber....) 

Also, I'll take your advice about fitting flat washers too Bess

Once again folks, thank you very, very much for your help......