Rotor/Stator help needed

Too hi of rpm can flex crank end to rub out the stator and so can a single over tight primary chain event. If the stator and rotor still working then can just clean up and put back after figuring out what did it and if it may still be doing it.
 
I wrapped 1 layer of blue painter's tape around the rotor, put the cover on and spun the crank (kicked over a few times with the plugs out). If the tape is clean, you're good. If the tape is galled a bit, look to see where it's hitting. If you're lucky, a trace amount of the tape will transfer to the tight spot on the stator. A little sanding down with emery cloth on the rotor or a sanding drum on the stator. Repeat until the tape is clean. If the galling isn't bad on that rotor, you can sand it down smooth and use it. New stator is about $100. I use the Emgo/Wassell 16A - same price as the standard 10A from my local guy.

On the Commando, I cut a strip of plastic out of a milk carton and fit it between the rotor and stator before tightening down the stator - works like a champ!

The AMC setup with the stator mounted to the outer cover is just another reason why they went bankrupt. 14 screws in that cover and it'll still leak if you don't follow a precise procedure.
 
Looks like a previous owner did not take care on bolting up the stator.
Or maybe worse.-I would remove rotor and mount a clock gauge to see if crankshaft runs true first. Also, With a clock gauge mounted, on crankshaft insert a hollow bar and try to bend crank up and down- if the run out is .002 -.005 thou I wouldn’t’ worry, but if it is more, consider that the main bearing on that side is on the way out.
When finally bolting stator, use a .005 thou feeler gauge to obtain an equal air gap all the way round before you finally tighten the nuts. HTH.
 
Bernhard said:
When finally bolting stator, use a .005 thou feeler gauge to obtain an equal air gap all the way round before you finally tighten the nuts. HTH.
Click to expand...

You'll need a very tiny helper to crawl inside the primary to measure the gap as you slip the stator on; the stator mounts inside the outer primary cover!
 
This is my method for bolting together an AMC primary:

If unsure of the flatness of either side, deck the inner and outer primary. I use a pretty crude but effective decking process - I have a piece of granite I took out of a store a couple years ago. I place several stick-on 220 grit sanding disks on the granite and slide the piece around on on it until I see bright metal everywhere.

Once both sides are straight and clean, I make sure all screws are clean and threads in the inner primary are all clear.

I spread a thin layer of Permatex Motoseal 1 (or Yamabond - any of the good grey non-silicone ones) on the inner primary and install the gasket.

I spread a thin layer of Motoseal on the outer, feed the stator wires through the hole, and carefully slide the outer into place, making sure outer is on both locating pins, but not tight down

I install all the screws running them in about 12 turns. On my Ranger, about 14-15 turns is tight. I use a speed wrench with a Snap-on straight screwdriver socket.

Once all the screws are in, I snug them down, working from the top and bottom in the center of the cover to both ends.

I run through this one more time, making sure all the screws are tight - maybe 8-10 ft-lbs.

At this point, you should a nice, even bead of motoseal along the joining seam. After an hour or so, I clean this off with an Exacto knife and a bit of Acetone.

The normal weeping spot is that funky notch on the inner primary just behind the drain screw. I make sure there's plenty of Motoseal in that area.
 
grandpaul said:
Bernhard said:
When finally bolting stator, use a .005 thou feeler gauge to obtain an equal air gap all the way round before you finally tighten the nuts. HTH.
Click to expand...

You'll need a very tiny helper to crawl inside the primary to measure the gap as you slip the stator on; the stator mounts inside the outer primary cover!
Click to expand...


Ooohps :!:
Please excuse my ignorance, as I am not familiar with this model, I should have looked at the photos more closely.
 
I fought trying to remove and install the N15 cover without moving the footpeg and would have sworn it was impossible to do, but on my 3rd go-round, I figured out the Chinese torture puzzle.

P11s are especially wonderful with the footpeg mount on the center bolt!

...Better than Rickman footpegs welded to the EXHAUST PIPES! (on some BSAs)
 
I take it that that is a metric clock :?:
If so, how much is the runout in inches :?:

does the crank have ant play as per checking the bearings :?:
 
If you haven't had the crank out for a look, and at the state of the bearings, its too early to say whats doing ??
Using old bearings, and not cleaning out the crank sludge trap is risky business at the best of times.

On the other hand, once the stator is hogged out far enough, it'll have enough clearance to run happily !
 
Yes, the only true way to find out if crank has any run out is with it mounted between centres.
 
"Bit of background context on how I came to own it. It was sold to me on the basis that the engine and gearbox had been done, and I paid (a premium" quote.

I would always be wary on statement like this; can the owner produce any invoices, bills, e.t.c.?
Sounds like the previous owner knew of the previous problem to me.
It’s always buyer beware, I’m afraid.
 
I think its time for a strip down.

Take the motor apart - its really not that complicated. This will give you a chance to check out the valves, guides and exhaust threads on the head; the state of the pistons and rings, and the bore clearance in the cylinders; split the case and check the cam and state of the crank.

If the engine was re-done, the head and cylinders won't cost anything.

This will give you a chance to check out the crank - perhaps it wasn't assembled properly. Check the crank for runout and the condition of the journals. While at it, have the crank, rods, pistons and rings dynamically balanced. 80-84% seems to work well in a P11.

Best case scenario, couple hundred bucks for the balance and gasket set, and you'll know the engine is right.

If the crank is bent, any Atlas crank will be a straight swap, and you could use a 750 Commando crank since you'll be re-balancing anyway.

If you find the head was never done, or the cylinders are worn, bearings shot, etc., it could all be done for under a grand if you do all the assembly yourself. If you replace the bearings, use a superblend on the drive side and a ball bearing on the timing side.
 
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