Steve, You don’t need to tap the crankcase. Presumably the stripped thread has left a clearance hole, so what you need to do is remove the camshaft and tap the locating hole in the bronze bearing. Make sure you tap the right hole not the oil feed one. You don’t need a tapped hole in both the crankcase and the bush. You will need to take out the valves and tappet blocks to get the camshaft out but all of that is possible without removing the engine. Good luck.
Alan and Nick, many thanks for the suggestions. Previous discussions have concentrated on differences in assembly, but having looked at another crankcase and the illustrations in the parts list, then of course the threaded hole in the crankcase is not necessary if the set screw threads directly into the bronze bearing. Nick, how does one apply sufficient care to avoid swarf creeping in all over the place, as sod's law of swarf distribution might threaten?
(23-08-2021, 10:02 PM)Steve kay Wrote: Alan and Nick, many thanks for the suggestions. Previous discussions have concentrated on differences in assembly, but having looked at another crankcase and the illustrations in the parts list, then of course the threaded hole in the crankcase is not necessary if the set screw threads directly into the bronze bearing. Nick, how does one apply sufficient care to avoid swarf creeping in all over the place, as sod's law of swarf distribution might threaten?
Rags and grease. Rags in the opening left by removal of the dynamo. Possibly if you degrease it sufficiently you could use gaffer tape over the opening. As for the locating hole in the bush, it's a close fit into the crank case and a close fit against the cam, so there isn't really anywhere for the swarf from the tap to go. Grease is surprisingly sticky and thus works pretty well for retrieving the bronze swarf. I thought there was a thread on the forum that covers this but a quick search hasn't revealed it yet.
(23-08-2021, 10:02 PM)Steve kay Wrote: Alan and Nick, many thanks for the suggestions. Previous discussions have concentrated on differences in assembly, but having looked at another crankcase and the illustrations in the parts list, then of course the threaded hole in the crankcase is not necessary if the set screw threads directly into the bronze bearing. Nick, how does one apply sufficient care to avoid swarf creeping in all over the place, as sod's law of swarf distribution might threaten?
Rags and grease. Rags in the opening left by removal of the dynamo. Possibly if you degrease it sufficiently you could use gaffer tape over the opening. As for the locating hole in the bush, it's a close fit into the crank case and a close fit against the cam, so there isn't really anywhere for the swarf from the tap to go. Grease is surprisingly sticky and thus works pretty well for retrieving the bronze swarf. I thought there was a thread on the forum that covers this but a quick search hasn't revealed it yet.
I go the other way and try to eliminate grease.
When faced with those sort of compromise jobs I usually clean well with brake cleaner, duck tape over the parts that I can, and have a vacuum cleaner pointed at the swarf running whist I make any chips. Works well.
Drove over to Aberedw for a walk on the “rocks” (as the hillside is called). Liz’s new hat seems to have stopped the complaints about cold ears. Unfortunately somewhere on the run back the manual advance jammed full on and the car stalled at a junction. Lucky it’s so light and could be pushed off the main carriageway. Soon un-jammed the offending dizzy plate and we were on our way.
I took the tourer for a short run this morning having spent a couple of days last week on oil leaks. I decided to have go at Colin Ayre's fix by cleaning up around the block to crankcase join with the aim of applying a silicon bead to, hopefully, stop the oil leak. In order to clean it all properly I had to remove the timing gear cover, at which point I found that the bolts securing it were not as tight as they should have been and the camshaft locating bolt was also not particularly tight. So cleaned the block to crankcase joint with solvents and applied a small bead of JB Weld Ultimate Grey silicon around the join , made a new gasket for the timing gear cover and assembled with Permatex Form-a-gasket sealant and made sure everything was tight. So when I got back from the run, lo and behold there was no oil flooding down onto the chassis rails. It will be interesting to see how long the fix lasts. O course, I cannot be sure that it was the block joint leaking having found the other bits not properly tight. We will see!
Peter, good luck with your attempt to squirt seal the block/ crankcase joint, I will say nothing, other than that Jamie sells a very good silicon gasket.
Thanks for camshaft locating bolt thoughts, I will proceed when returning from a week’s hols. A whole week out of the workshop! What I have yet attempted is correctly lining up the hole in the bronze bush. Part of it is clearly visible, if I raid a nearby supply of knitting needles should I be able to wiggle it back into alignment?
To show what a small world we happily live in, having gone on an international journey yesterday, into England, being in Shropshire I dropped by to Pete Martin, owners of various Sevens. After being plied with scones and jam by his dear lady wife, conversation turned to technical challenges. Talking about what to do with the locating bolt, I mentioned the suggestion on the forum by Alan Fairless. I was then taken to the workshop and shown the engine built by Alan for Pete’s trials special.
25-08-2021, 09:53 AM (This post was last modified: 25-08-2021, 09:55 AM by Alan.)
Steve. Go to Smiths and buy a magic marker pen or borrow one. Before you put the bronze bush back in, mark a line lengthways through the peg hole in the bush. Fit cam with bush about half way in. Rotate bush until you can see the line through the bolt hole in the crankcase. Now push the bush in until the holes line up.
26-08-2021, 04:03 PM (This post was last modified: 26-08-2021, 04:13 PM by Malcolm Parker.)
Just returned from the Pre-War Austin 7 Club's Heather and Honey Run, a 35 mile scenic road run based near Thirsk, followed by a lunch. The run is a Charity event for the Yorkshire Air Ambulance.
42 cars took part, the vast majority of which were pre-war. Ten sevens took part including the ex Geoff Winder Speedy, 3 Type 65/Nippys, 2 SWB box saloons, 2 Opals, a Swallow Sports and a Chummy.
