Should the Regulator be too Hot to Touch?

The raised lip is on the notched ring that holds the ATU onto the end of the cam, not the little disc with the lines scribed on it. You can see it in my pic between the 2 yellow arrows and under the spring. See that raised ridge just above the lower yellow arrow? Now look at your pic - no raised ridge showing on the notched ring - because it's on backwards. If the shop installed the ATU then they are the ones who put the ring on wrong.

I'm confused as to which part is backwards? Do you mean this ring
redlineadvance2.jpg
 
Oh, the ring with the tabs around it (the green arrows are pointing at it)?
redlineadvance3.jpg



I think they had to tighten that ring with a screwdriver and hammer (it requires a special tool that I haven't got either). I hope that's the problem, because it was a bitch to r&r. Is there another/better/easier way to loosen/tighten it?
 
I think a shock spring tool( the tool to make the spring's stiffer on your shock's) work's, but a small chisle and small hammer will do the job. Just tap the nut easily, so you do not cut it too badly. Same thing when tightening. And remember lefty= loosy, righty= tighty.
 
Thanks, Gordon. Sounds like a plan. I'll take a shot at it (metaphorically) tomorrow.
With fingers crossed...
 
Yes, that's the ring (finally, lol). I don't know if there is a special tool for it. Even the factory shop manual tells you to use a hammer and punch. I move around it and hit in as many notches as possible, not just one.

And don't forget to pull the unit off the cam so you can check the locating pin. This may have been the problem all along. The pin fell out, the advance unit turned slightly on the cam, and this threw the timing off to the point that you couldn't adjust it back to spec with the timing plate.
 
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I just R&R'd the advance unit. Here's what I found upon DISassembly:

I removed the center nut/washer and slid the cam shaft out through the points side (it looked fine):
advancereassemble1.jpg


I removed the cir-clips holding the weights/springs and slid them off their posts. As you can see, the raised flange on the notched nut is obviously facing inward, so it cannot be seen from here. Inside the hole, you can just make out the end of the cam shaft and its key (around 7:30):
advancereassemble2.jpg


I don't think you guys requested that I remove the advance backing plate, but I was going to just to see what's behind it. Unfortunately, I couldn't get this screw-thingy off (it wouldn't pull or twist off by-hand, so I left it on). You can see the little positioning pin(?) to the left of the screw-thingy, which I reckoned is supposed to sit between a pair of notches on the notched nut to lock it in place:
advancereassemble3.jpg


As you can see, there's a scrape mark/indentation where that positioning pin ground against the inside face of the notched nut:
advancereassemble4.jpg



With the advance components removed, other than the pin in the cam shaft (which looked fine), I didn't see any other pins or keys around the hole in the advance side where the cam shaft fit through. So I began reassembling, tightening the notched nut until that positioning pin was locked as you see it here (note: the flange is now facing outward, towards the camera, per your suggestion):
advancereassemble5.jpg


Then, I installed the round spacer with the engraved arrow (note the key in the cam shaft is properly located in the round spacer's keyhole):
advancereassemble6.jpg


I lightly greased the weight posts and installed the weights/springs, followed by the weight cir-clips (not pictured). Note: the engraved lines in the backing plate and round spacer are aligned as they were originally:
advancereassemble7.jpg



After that, I retested the timing with the timing light and found it off. So I re-gapped the points to .35mm and re-tested with the timing light. Still off... So I tried re-gapping the points with the dwell meter and was able to get both sets pretty close to the 11 degree line on the dwell meter (set to 8-cylinder - remember, my current dwell meter offers only 6- or 8-cylinder settings).

Then, I re-timed it with the timing light, which went well. Trouble occurred when I increased the engine RPMs above idle. By the time I got to ~2300rpm, the engine (I think mainly the left cylinder, but not positive?) began back-firing. I did a quick timing light check and noted that the timing marks were just sitting between the "F" lines and NOT advancing as they had done prior to today. I pushed on the weights to be sure they were moving freely (they were), so I think either that notched nut was installed correctly originally or I must've done something wrong when I reinstalled the advance unit setup. Though, as you can see in the photos, there's not much to get wrong???

Is everyone sure that notched nut is supposed to go on with the raised flange pointing outwards? That's the only thing that's different since I timed it yesterday (and the timing marks moved as the RPMs increased).
 
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Is everyone sure that notched nut is supposed to go on with the raised flange pointing outwards?

It works for 5T, so it should work for you, right? Is everything working mechanically that way? Would it work better the other way? Would it make any difference? You should be able to tell by looking.
 
Hi xjwmx and thanks for popping in.
It looked like it should fit the way it is now, but this is the first time I've removed it and, as I said, up until today, the advance had always worked. So if the notched nut is on correctly, I had to've gotten something else wrong when I reassembled the advance unit. Can you see anything that looks wrong in the photos?

The only thing that looks off is the position of the right weight in the last photo. It looks like the limiting tab (I'm not sure what its official name is, but the metal piece that limits the travel of the weights) is too close to the outer edge of the right weight. But I checked the movement of both weights after I reassembled everything, and, again, after I noticed the timing marks not advancing with increased RPMs. So it must shift position once the cir-clip is in place.
 
Can you see anything that looks wrong in the photos?

No, but the only mechanical advance I ever had was on an MGB. So the advance isn't working? That's verified with the timing light?

You should be able to see why it's not working, at this point, and change that thing to make it work. You have to figure out how it's supposed to work first, though. The flowchart it runs through when it operates correctly, that is.
 
No, but the only mechanical advance I ever had was on an MGB. So the advance isn't working? That's verified with the timing light?

Correct. The timing mark on the rotor lines up perfectly (between the "F" lines on the stator) at idle, but it remains there even at 2300 rpm and the engine begins to backfire, which it wasn't doing prior to today. Does that make sense.

By the way, I've got a Spitfire (which has electronic ignition).
 
Well, you have to figure out why that is. Why it's shitting on you and make it stop.

I liked Spitfires. Although they were undoubtedly the cheapest car ever made. Not in the same league as MGB, but that ain't sayin much. LOL. Really fun cars anyway though.
 
freddy, make sure that the rod rotates easily inside the camshaft. A little lube on the bushing's should help if it seems to 'stick'. How it work's is as the camshaft rotate's, the faster the engine rev's, the weight's will move outward, rotating the shaft in turn, advancing the timing.( open the point's sooner)
 
Something doesn't look right to me about this :

advancereassemble7.jpg


The armatures seem bound under the stops to me. Anyone else feel that way?

This is what I expect to see :

3c9fb8e471003b9a02c36eee44fb_grande.jpg


notice that the armatures have room to move?
 
Well, you almost had it but you didn't go quite far enough. The advance unit has to be removed from the cam to check the pin and for the proper location. If it was stuck, you just need to gently pry it, use penetrating oil, whatever, to get it off. Re-install with anti-seize on the cam so it will come off in the future without this happening again.

That pin you noted (red arrow) on the front of the unit is located directly above the alignment notch on the backside of the advance unit .....

AdvancePinFront.jpg


Try this - set the motor at TDC (on the "T" mark) and check the pin location. If the advance unit is properly aligned, the pin will be straight up or straight down. If it's off, the advance unit isn't aligned properly on the cam and that's why the timing is off and can't be dialed in.
 
Freddy's advance unit is practically new. Maybe that's why it's so tight? Mine has lots of slop in it, lol, but it's the original. I think I'm going to have to peen the ends of the weights soon to reduce the amount of advance.
 
Something doesn't look right to me about this :
advancereassemble7.jpg

The armatures seem bound under the stops to me. Anyone else feel that way?
After I assembled everything, I did check that the weights pivoted freely, but I'll recheck again tomorrow. I hadn't yet installed the cir-clips onto the posts that hold the weights onto the advance backplate when I took that photo, so they (the weights) may not be sitting flat against the back plate and that might(?) account for their appearing to be locked in place by the limiting tabs.
Again, I'll recheck the space and freeplay tomorrow.


Well, you almost had it but you didn't go quite far enough. The advance unit has to be removed from the cam to check the pin and for the proper location. If it was stuck, you just need to gently pry it, use penetrating oil, whatever, to get it off. Re-install with anti-seize on the cam so it will come off in the future without this happening again.
Before I force/break the wrong thing, so you're saying this screw-thingy on the shaft in front of the advance base plate (the part the notched nut screws onto) just pulls off?
advancereassemble3.jpg



I'll try some penetrating oil and then see if I can wedge something behind it to lever it off. It seemed like it was pressed-on, but I'll give it another try tomorrow.


Try this - set the motor at TDC (on the "T" mark) and check the pin location. If the advance unit is properly aligned, the pin will be straight up or straight down. If it's off, the advance unit isn't aligned properly on the cam and that's why the timing is off and can't be dialed in.

Will-do.
 
The threads you're seeing are on the cam end - they won't come off. Just the advance unit pulls off. Take a look at this link. It has pics of a later model cam with no advance unit installed. There are also no bushings in that cam because there is no advance rod used on the later models. Locating the advance unit on the pin in the cam is what ties the points into the spinning cam and makes them open at the right time. This is what we're trying to determine here - whether your advance unit is located in the proper spot on the cam so the timing is correct. If the locating pin fell out or sheared off or something, that could allow the advance to move or twist on the cam end, throwing the timing off .....

http://www.650motorcycles.com/CamTiming2.html

Your current new problem appears to be a binding advance rod for some reason. With the motor off, you should be able to rotate the advance rod by hand about a quarter turn. Just grab the little disc with the scribed line and arrow that the weights hook into and turn it. When you let go, it should snap back to the retarded position. Yours appears to be stuck in the retarded position, not advancing as you rev the bike up.
 
i had a similar problem, the pin that holds the ATU to the shaft came out. and looking at those pics, i think i need to replace my ATU, the dogs on the weights are nowhere near that size, and there's a lot more play....

and i agree that the weights are being held in place by the ATU's body. i would pry the tabs out slightly to see if that helps, they look to be at too tight an angle, like they've been squeezed in...

beautiful close up pics, btw, freddy,
 
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