Talk Morgan Forums Morgan Sports Cars Maintenance & Servicing Narrow pulley conversion

5/16-20 is BSC, British Standard Cycle, also found more commonly as 26TPI. A popular thread on early 3 wheeled Morgans.

Not much on that thread standard. You do find the 26 TPI.

Really odd size though this 5/16-20. I wonder when this replacement pump was made (suspect 25-30 yrs ago). I just had a chap rebuild it, is what he does. So it’s all better than new, impeller now with so many vanes the radiator won’t know what hit it. As long as I can keep the pulley from flying off and bouncing down the lane like an errant hockey puck.

Will post again when I have successfully mated a nut to the threads- am taking it slow and careful because some who have read my thread on why I’m changing my crosshead (long story!), it all started innocently enough trying to throw on a pair of brake reaction bars and stripping the bottom cm of my original oiler bolt. A can of worms! It’s going really well, albeit taking me ages. As most of you probably know every single thing requires one to strip clean polish repair reengineer paint coat oil grease pack, and last but not least, furnish with fresh nuts bolts washers (trying out these nord locks) etc!

Then again, that was sort of the whole point of me getting the car!

It ended up actually being an M8-1.25, rather than the 5/16-20.

New problem - the generator pulley seems too far back when compared to the water pump and crank pulley. See pics - the generator mounts to the rear of the mounting plate. If I move it to the front I think I’ll be off too much in the other direction. I cant get the water pump pulley on any further, it’s bottomed out. Any ideas?

Front and side views here:

Looking at the alignment I suspect the fan belt would not last too long. Should be a simple enough job to make up spacers to get things back into line..Unless there is something I have missed..?

My thoughts too - a couple of washers in the right places should sort that out I'd have thought.

The problem is the way the generator connects to the bracket. It had been mounted, as I believe it is usually, to the back side of the rear lug of the bracket. So the only way to space it there with washers or whatever, will push the generator further to the rear. In order to space it forward you need to position the generator rear lug on the front side of that bracket. I haven’t done it yet, but am worried that this will get me too far forward. But I’ll give it a try.

Sorry I can not remember the "bracket" set up on your type of engine though if the type bolted to the block, you could perhaps file the holes through the bracket to make the necessary final adjustment to bracket positioning..?

That is a good idea. I’ll start with repositioning the generator to the front side of the bracket, with a spacer on the front mount. If that overcompensates I’ll reposition the mount bracket where it sits on the engine.

Is the bracket mounted correctly?

Can't you put washers/ spacers on the bolts that hold the bracket to the engine to move the bracket forward?