Hi All

The last few trips in the van have been punctuated with the odd misfire and occasional starting problems. It culminated yesterday with an almost constant problem, with the car cutting out every few hundred yards. I discovered that the ignition switch on the SM5 switchbox could be fiddled with to help with the problem.  An easy fix, or so I thought. I’ve had the box to pieces cleaned the contacts checked for continuity etc etc.  But putting the box back in the car I find that …

Switching from off to summer charge moves the ammeter needle to about 2 amp discharge. That’s good!
Switching it further to full charge the ammeter needle stays at 2 amps. That’s good.
Switching it back to half charge causes the ammeter to register zero. That’s bad.
Switching it on to full charge the needle remains on zero. That is also bad.
Switching it off then back on and the ammeter registers 2 amp discharge. 

The switching back from full charge to half charge almost always results in zero amps, but occasionally the needle stays on 2 amps.

I’ve a feeling that this is the cause of the misfire and cutting out but what could cause such strange behaviour. Could it be the diode cut out or is it still bad contacts in the switch box? I have a separate earth to the bolt on the starter motor housing and one to the floor pan and chassis.

Thanks in advance for any help, comments 

Howard

After watching some of the trials Sevens were being used in on U - Tube and  hearing some of the high RPMs  that the engines were subjected to, I started to wonder what the red line for a stock unmodified engine would be.

Is there a "do not exceed"  number of RPMs?

Cheers,
Stephen

Hope still springs eternal.
I'll have two, please.https://www.ebay.co.uk/itm/326234384003?

I am hoping to have the opportunity to spend around £1500, possibly a little more, on a hobby lathe. Appreciating there are occassionally second hand lathes to be had I am looking for suggestions for a new hobby lathe, possibly including milling attachment. I am tending towards table top as appreciate a stand will add to the required budget. I have a 30A supply in my workshop if needed. Whilst there are the obvious from Clark etc I am sure there are others I should be looking at.
I would appreciate any knowledbabgle souls offering their twopenneth and of course from Tony as the resident 'lathe man'.

Thanks
Andy

A "Potter" precision bench lathe - almost certainly brought over during WW2. It's the usual 'house clearance' sale, open to offers and so could be a bargain if you're near Salisbury
https://store.lathes.co.uk/adverts/for-s...potter-usa
http://www.lathes.co.uk/potter

I have removed the centre main bearing from the 3 bearing crankcase  to fit a Phoenix pressure fed 2 bearing crank. I now have no idea how to provide a block stud for the centre of the right hand side of the block where the centre main bolt used to be.

What have other people done to sort the missing stud which is part of the centre main hold down stud/bolt?

Also what do people do about providing additional lubrication to the plain cam centre bearing? Maybe a track cut into the bearing surface may help?

Thanks for any suggestions for the above.
Bruce

Pal of mine sent me this photo, taken at the Rescue Wooden Boats Centre at Siffkey in Norfolk.

   

Hi All,
Tim Reynolds posted some photos several years ago on the old forum which are now unavailable. These were of modified cam followers and asymmetric if I remember correctly.
Tim if you are reading this I would appreciate it greatly if you could repost them on the new forum as this is something I am currently investigating.

Many thaks,

Paul N-M

I'm new to this forum so please excuse me if I've not got things right (yet).

I'm looking for an oil pressure gauge for my Chummy, ideally 0-20 psi.  Cosmetic condition isn't important; I just want one that works.

Hi, I am trying to sort out my RN box but need some information on the shape of the bulkhead above the gearbox. I'm trying to determine if the recess behind the engine is uniform all the way down or is it tapered to become flush with the bulkhead at gearbox height. Not sure if that makes any sense but if anybody could post a photo of that area taken from the inside it would be a great help. Many thanks in advance.