screw-in HT leads?

Post by **Pascal** » Fri Jul 13, 2007 7:56 pm

Hi,

On a 1970 moggy would you expect the HT leads to be 'push-in' or 'screw-in'?

Regards

Post by **bigginger** » Fri Jul 13, 2007 7:58 pm

Push. Never seen them anything else.

Post by **Packedup** » Fri Jul 13, 2007 9:42 pm

I have no idea about the ages of the various (now stupidly skipped

) a series engines I knew had come out of various Minors, but IIRC at least half of them had screw fit side entry caps.

Post by **bigginger** » Fri Jul 13, 2007 9:53 pm

Fair enough

Post by **RogerRust** » Sat Jul 14, 2007 8:35 am

I'll get shot down, I expect, but 948 and earlier are screw in and 1098 are push fit.

RR ducks and waits for emails!!

Post by **JimK** » Sat Jul 14, 2007 9:12 am

I think it changed to push-fit sometime around '66. That's based partly on hearsay, and partly on the fact that the leads are screw-fit on our '65 car and push-fit on our '68 car.

Post by **Packedup** » Sat Jul 14, 2007 10:06 am

Having been cap hunting (the "quality" pattern rotor arm I bought a few months ago has literally dusted the contacts in the cap!) recently I think a lot of people will have push fit where once there was screw - The screw fit caps can cost up to 20 odd quid from some places, the push fit are *considerably* cheaper!

Post by **bmcecosse** » Sat Jul 14, 2007 7:57 pm

Aye - all the originals will long have departed this planet.

Post by **Judge** » Sat Jul 14, 2007 8:30 pm

RogerRust wrote:RR ducks and waits for emails!!

I know the feeling

Post by **dunketh** » Mon Jul 16, 2007 10:54 am

I had screw in ones on my '66 1098 and on the MG engine I bought.

Since replaced with push fit though - frankly I don't see it makes any difference how they connect.

Post by **Stig** » Mon Jul 16, 2007 3:33 pm

I recently had a problem with a replacement side-entry screw-in cap I'd fitted to the Sprite. The screws didn't go in far enough - they had pierced the insulation but weren't always making good enough contact with the carbon string conductor in the middle. One of the leads was therefore much higher resistance than the others - hence only having 3 cylinders whenever I accelerated!

If you're about to fit a new cap then have a look at where the leads would go in to see how far the screws poke down - more than half-way would be good.

Post by **Packedup** » Mon Jul 16, 2007 4:27 pm

Hmm, I wonder if that's part of the problem I've got with the Midget. Nah, it couldn't be that easy to fix...

The joys of the screw in is the leads are very cheap - All you need is a length of copper HT wire, the plug caps screw in one end and the dizzy screws to it the other. Trouble is, the caps are quite pricey! I don't really see any advantages on a Minor (other than cheap leads), but on a Spridget a push fit top entry cap looks like it would run very close to the steering column

Post by **Stig** » Mon Jul 16, 2007 4:34 pm

Maybe with copper-cored leads it would've been OK. If you've got copper leads though where is the 10-25kOhm resistance going to come from? It's not only for radio suppression but for the best spark too according to Mr. Vizard.

Post by **Packedup** » Mon Jul 16, 2007 5:06 pm

I've got NGK resistance caps, though I think they're only marked 5k.

I've also got a dodgy Intermotor coil, horizontally mounted (and last year there were a lot of posts about failing horizontally mounted coils on Minors...) so I think I've other things to worry about with the HT before I need to think about the actual spark! My cap has been carved up by a nasty cheap rotor arm too...

Personally (and I seem to recall Vizard is an advocate too), I go with if you can fit copper HT leads, then do