A7 Sludge trap plug problems

[Degsy]

Hi Folks
I am rebuilding an A7 based Bobber that has been sitting outside unused for a some years (see photo), it was built in 1980 from a 1952 engine and a 1953 frame. It was seized due to rust in the cylinder and has needed new pistons and rebore. 
I thought I should go a bit further and open up the crankcases and do the sludge trap.  But I am having problems removing the plugs.
Both plugs are not flush (see photos), I read somewhere that this is a concern as the plug might block the oilway if it is too far in.  I assume I have a small bearing crank  as there is no sludge trap locating bolt on the flywheel and I guess there is no sludge tube, so what stops the plug going in too far on a small bearing crank?
There is evidence of previous struggles getting the plugs out.  I have now stripped the internal Allen key hole trying to get it out, in my defence it was already damaged. 
I have tried the other plug and am reluctant to go heavy on the slotted plug and wreck it also.
But there is something odd about the slotted plug, there is what appears to be a pin above it in the crank web (see photo) and the pin or screw has been roughly punched over to hold it in place, if it is a pin this would not keep it in place so I assume this is a screw, but why? And is it the reason I am struggling to get the plug out?    The BSA A7 parts diagrams show no pin here, is this a non standard bodge?  does anyone have an idea what is going on?
Help please!
At the moment my best option seems to be to just put things back together and hope for the best.
Degsy

[Rex]

As I recall when I did mine (engine of a similar age) the plug could be wound too far in and effectively block the oil supply. I would think that on yours the oil supply must have been constricted with the plug that far in.
I aimed to get the new plugs on mine flush with the crank cheek, and with that the plug was indexed to allow a portion of the bottom edge of the plug to be ground off to allow the full flow of oil from the oil feed hole.
Be careful if you drill those plugs out as there's not much space behind them, and too much with the drill will see the crank itself damaged.
 

[Swarfcut]

 Plenty on the Forum about the varying degrees of violence and guile to get them out.  Plus YouTube howto's.  Plan on obtaining replacements, and have a look in the topic "Great Mechanical Disasters"  What's inside is pictured there.

 Mystery plug seals the oilway leading down to the timing side journal, inside the web.

 Give us an intro, this story sounds rather good. With these engines Hope is certainly not an option. You need to show it who's boss.

 Swarfy.

[Degsy]

Hi Guys

Yes I think they will have to come out somehow, the blocking of the oily sounds scary.  I watched some of the Youtube hoots and thought this should be ok, but it does not seem so easy.

Any ideas about what that pin or grub screw in the crank web might be doing? it is not standard to have something there is it?

[Degsy]

Thanks Swarfy, missed your comment on the mystery plug in last email.  But why would there be a plug there? is it filling a hole created during the manufacturing?  I was worried it was a screw holding the plug in, so one less thing to worry about.

I noticed the bike round the corner from me in Edinburgh it was rusting away in a front garden, kept walking past it and eventually knocked on the door and it turned out he had the bike was in his back garden and had moved it to the front in the hope someone might see it and offer to buy it.  So just this January I bought it, having recently finished my Norton Commando and I having said no more projects but I always fancied a BSA and this one was a bit different.
Needs a bit of work though See photos. 
The A7 frame has been modified to give it a more "Bobber fork angle" and the front end is off a 1971 A65 Lightning or maybe a T120 Triumph etc. it was a common front end back then, except it has 4" longer fork tubes, which were available but rare these days I bought new ones from Austria although they are made in the UK, they weren't any more expensive than refurbishing the old ones.
I have had the frame and various parts powder coated and nearly at the stage of building it back up, so I'll keep you posted on progress.
Degsy

[Degsy]

A couple of images didn't upload here they are

[Minto]

That looks a very interesting and fun project, I've always thought that the plunger A10 lends itself naturally to being "bobbered".
Definitely don't just bolt it back up without sorting those plugs and sludge trap, the plugs are definitely too far in and will be covering the oilway. My crank is out at present so I'll try to find time to remove my plugs over the next day or so to see how far down the hole the oilway is.
My guess about the mystery plug screw pin thing is, a previous owner has screwed that trap plug in way too far then had the same trouble removing it and as it is restricting crank oil flow, drilled the crank, through the trap plug in an effort to relieve the oil restriction, then plugged the top section of the hole drilled in the crank. If that makes sense.
All the best
Jase

[Degsy]

There is something about the lines of the plunger frame that is pleasing to the eye, especially with the longer fork angle, should look good when its done.

Interesting theory about the mystery plug, if it was drilled through to the plug it might explain how hard it is to remove, although it seems that stuck plugs is quite common and drilling out is the last resort.  I will try with the various methods suggested here and on youtube and here, but I feel at least one of them will need drilling out and I don't fancy that, still it's a challenge and all part of the fun!  I have the new plugs on order.

Cheers

Degsy

[berger]

that plug in the crank web is a factory drilling for the oil way that the factory then put a blanking plug in as swarfy has pointed out

[berger]

the drive side plug hole is drilled 44mm deep into the crank the same diameter as the plug. the timing side plug hole is drilled 11mm into the crank and has a smaller diameter big end feed hole. the plug should only go in this hole about 4 threads or the oil will be restricted, it looks like  yours has blanked it off completely . I put my timing side plug in tight marked it and filed a relief in the plug to get maximum oil flow, I think there are pictures on the forum somewhere

[Minto]

HeyDegsy, sorry I missed Swarfy's post. Berger and Swarfy both have way more experience and knowledge about these things than I do, so would definitely go with what they say. I was just comparing your pics with some pics of my own crank, mine doesn't appear to have that plug, just a couple of punch marks.
Regards
Jase

[berger]

minto the punch marks are where the plug is to secure it, they all have two punch marks like that, unless some one has been messing and made a mess like Degsy's. if you look at the timing side journal you will see the drilling going up into the web, then they drill down from where that plug is to meet up with the other one, and so that drilling has to be plugged. now IF! there was such a thing as a bendy drill there would be no need to do two drillings ooops I forgot there is such a thing as a bendy drill and most are made in china and I just remembered loads of crud hides under that plugged bit , or it did on mine until I started prodding it.

[Minto]

Berger, it all makes sense now. Gonna have to have a closer look when I get home, that is well blended in with the rest of the crank web.
Jase

[berger]

Degsy what is going on with your timing side journal I am confused, can you take a picture please

[RichardL]

Degsy,

Welcome to the forum. Obviously, the option to weld a nut to the face of the inset plug is off the table. Perhaps you have seen this article about the sludge trap and the suggestion to drill a 5/16" hole in the plug, then drive a 5/16" allen key into that hole.  If that don't work, I believe you will be obliged to drill successively larger holes in the plug until a robust easy-out has a fairly easy job of extracting a narrow ring of threads that remain from the plug.  For the slotted plug, the welding option is still there, but you will have committed to drilling anyway, so why change techniques after that?

https://cybermotorcycle.com/archives/bsa-super-rocket/endplug.htm

Richard L