Alternator grommet, how to install new one...

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Good day to all,

Machine, 72 750 with the one center bolt primary cover attachment.

Leaks like stink through the felt clutch seal, the inner primary case gasket and last but not at all least, the 40 year old alternator grommet.

I am doing the thing, but having ordered a new alternator grommet from RGM, I find the new grommet to have quite a different appearance from my old one. New one has a long elephant trunk like tube on one side. Old one didn't....or the snout had been ripped off, that could be too.

Question. Which way is this new fangled grommet with the snout on it inserted in the inner primary case. Snout inside the case, or snout out the back towards the wire connectors? And why...why does it have this snout?

Be thankful for any tips and info... would be a bummer to put it in wrong and end up with more oil on the floor than all those leaks caused before the repair....
Thanks!
 
It goes on the inside, I think it just helps to guide the wires, they go hard from the heat inside the Primary, the only way to stop oil leaks from the primary is to run a belt drive, so much better and lest maintenance, or just replace all the seals inside, I now run a belt drive and never go back to a chain.

Ashley
 
I'm using the old chain drive and don't have any leaks from the primary, that is. First, yes, I think the trunk goes inside. When you install the gasket, put some silicone sealant on it too, both the hole it goes in and in with the wires, won't hurt anything. Then while you have the primary cover off, remove the large o-ring, clean the groove and put some silicone in the groove, not tons of it, and put the o-ring back on. Smear a tiny bit of silicone on the top of the o-ring before installing and torquing the center bolt down to 25 ft-lb, I even put a bit of silicone behind that large washer too. You need a good gasket from the engine to inner primary too, and silicone won't hurt there. Don't know why it's getting through the felt seal, I don't have that problem, do you over fill the primary or are you having oil from the engine seeping through the inner primary to crank case bolts? I put studs and nuts there and sealed with red locktite. This all depends on if your spacer behind the inner primary is right and you're not bending the inner case, if it's bent the outer will never fit right.

Dave
69S
 
Thanks for the tips, both of you. I will maybe give RGM a call too and ask their theory on this, as they may have designed it that way. They do a lot of self designed replacement parts.

I have no worries about the inner gasket. That leak was so simple to figure as I had been too lazy to use a gasket cement. The oil flies right about in the primary case evidently and what got between the inner primary and the motor block at the point they surround the crank shaft...just pooled up above the gasket and lo and behold, there was not any gasket cement and just three little screws to hold the gasket in place...and it ran down and out on the engine cases. Regular river the last couple months. The river running down the back of the inner primary case from the alternator grommet was easy to see the reason for too as when I opened the case, the grommet had a big age crack and that just funneled the oil right out the grommet and down the back of the primary case. Drip and run to front...and drip. Great stuff. The felt ring, also easy to figure as it was some forty years old, I am cheap bugger and every time I had to get in that deep...I just cleaned the seal up with brake cleaner, re-oiled it and reinserted it. Naturally the oil gets then turned to a glaze with the turning of the steel bushing it is supposed to seal off, and we know how well a glazed surface seals. Not very well. And those felt seals shrink too, but in the wrong direction. The sealing surface opens right up. So three "elementary my dear Watson" type leaks...all due to being too cheap/lazy to buy new parts and put em in. My fault. As to the snouted gasket, that was my question, as to why it was so made compared to the original...and how to install. Can't, even after 40 years of tinkering on this old lady...know everything about her, so I had to ask . LOL
Thanks...if RGM gives me a good reason for this design...I will pass it on here...good day to ya!
 
OK.... at RGM, Lawrence had only to say that he thought it would go with the long snout to the back of the primary case, to give the wire more support. No concrete reason. But, thinking about it, that might also make sense as if the snout is that direction and pointing up as it will be, any under air-pressure (blow-by through the crank seal and general air pressure from the chain and clutch spinning around) oil managing to get between the wire and the grommet from the inside, will then also have the height of the whole snout to travel before it can get out and leak. By that time it might just rather go the other way overnight and go back where it came from instead of on my floor. Water won't go too much into the primary that way either if the seal is supple and seals fairly well. ...rain and such will have better to do than try to go down that snout.

So that's what I've decided. Snout to outside. Thanks for the tips...and if any of you have a good reason that I be wrong...let me know fast...the lady wants to be fixed this evening :-) Take that as you may...
 
Mine was the orginal rubber so when I replaced it I put it in the same way with the trunk on the inside and I have owned my Norton since new, the trunk I think is used to keep the wires from touching the chain when running.

Ashley
 
Hi Ashley. Had the bike then awhile. Me too and my original had no snout on it, so they maybe used different grommets at different times. And maybe there is no good reason for the snout... but I bet the engineer/designer had something in mind. As far as it helping the chain not to damage the wire though, ...if the wire is THAT close to the chain...well no bit of soft rubber is gonna save much. Can't be the reason. The cable gets routed down into the middle of the space that is free of the chain anyway. I can see the sense of routing the cable so it doesn't enter the grommet at a down-hill angle...makes sense, but that snout can only be to add a form of sealing to the cable, nothing else. Not stiff or thick enough for any other purpose. My thoughts on putting the snout on the outside could be total BS...been known to have brain lapses...but right now it makes sense to me. Even sober, it makes sense :lol:

Does anyone have graphic proof of the mounting direction? Parts manual, blueprint type proof? Be indeed interested to see such. Thanks!
 
Trim or cut the snout off to convent length if it interferes with wire routing inside case. I zip tie leads to the cover mount stalk so wires don't vibe and oil drains down. Main thing about primary oil is not to add more than just touches chain at cold sag slack. Sealing cord groove valley can use a bit of RTV fill to help it mate to the cover w/o any goop or leaks there. Oil can weep out the 3 small mount bolt threads from crankcase side too. I like to replace them with loctited in studs.
 
Well look who the cat dragged in! Welcome back, hewho! :)

FWIW, my '72 parts list shows the snout facing in. That's how I've been running them, but they do leak. So does the felt seal and the rubber o-ring. Good excuse to go with a belt drive, except then I'd have to deal with the leaking crank seal...

Debby
 
Thanks... all of you...and yes, Debbie...cat did it's job. :lol:

If the manual shows it inside...Ok, maybe I do it that way then. Seems there are quite often a few leaks in the primary, from what I hear from you all. Mine DIDN'T leak till bout a year ago when some vehicle inspection man made me change the chain and drive sprockets, tranny and brake drum. Some stupid comment about the teeth being kinda like more pointed than his Doberman's. So just to get the stamp, I pulled it all apart and finally used the 21 tooth sprocket and the new brake drum I bought when I used to think I wanted to do things like that... in 74. Done a hundred thou now since I decided to buy the stuff back then. I think he just pulled my leg and his dog is in truth senile and has filed false teeth...one of them Gothic Vampire dogs. My sprockets looked fine to me...


Anyway...getting back to earth, I will do the tie wrap thing and put the snout inside then.... Gosh....anything just to please...or?

Thanks,
Greetings to you all...from outer Schnitzelland
 
Hey Hewho:

I just installed a new alternator grommet on my machine. Its a bit of a fiddle but I eventually got it in there. Be sure you have the rights size grommet (approx 1/2" diameter and 5/16 thick) and crush it back in on it inside diamter. I also used a drop of oil.

I'd go with a belt drive too but its too expensive for me at this point.

BC
 
Wish someone would post a picture of this "new type" grommet. Personally, I haven't used the Norton alternator grommet for a long time. What i do use is a good "used" sparkplug cover---I find them in the trash behind a BMW auto service shop. They are probably BMW ignition parts.
Anyway, I just fashion them to fit the inner case hole by grinding a groove around the large end. You can cut off anything longer than what you need/want on the small end. the 45 deg bend of the plug cover can be rotated any way you prefer---this I leave on the outside/backside of the inner case--usually pointing downwards.
I use three-Bond sealer on the case/grommet location and also after pulling the wires through---use sealer on the outside filling up the space where the wires come out.
These plug ends are made from silicone I think---they don't get hardened like the rubber ones.
 
Thanks...good idea with the spark plug cover ;-)

Got the grommet in this evening, snout to the inside, and the triple chain and clutch and such. Will finish tomorrow if the leads on that stator don't snap off on me. Stator is the original and the leads are brittle as heck, so it has cracked the green white rubber wire coating in a couple of places...like right at the point it goes into the stator and right where you have to bend the wires to get them in and out of the grommet one at a time. Nice...and at the stator end, not enough space to splice in new leads, so I will have to do a glob of silicon on top of the place to give it some stability so it doesn't just snap off one on the wires. Bummer.

Or...does someone have a better trick to make this stator and it's brittle wires last another hundred thou?

Please then let me know...gotta do the bed thing now...three in the morning LOL

Bye and thanks!
 
Have had the wire insulation break just as the wire enters the epoxy potting of the stator. A dab of silicone will protect that area. I'm with hobot on ty-wrapping the wire to the central stud boss. Have had the wires cut by the primary chain with too big a loop. Also have seen some have the stator turned around so the wire exit faces the chain - no good.

I guess I have never seen the grommet with a snout. Was it an 850 thing?
 
Got it all together now...no problems. Used the Silicon on the place where the wires go into the stator, used a bit to seal the snout, snout pointing down a bit to avoid running down of oil, used tie wraps too where they were suggested. Clutch plates cleaned etc. Used a stay plyable type gasket cement/sealer from I think Permatex on the inner primary Gasket and left the old rubber band in place, looked good and hadn't leaked anyway when I popped the primary open...so I don't think it will leak now. Thanks for the help and tips all. Wish all a nice Easter weekend and safe riding!
 
Sorry...just got my camera back today from the person that needed it more than I did. So no picture of the famous Snout. Just a tube type extension on the normal grommet and it did indeed all go together fine. Been for a test thrash around the block (15-20 miles) and seems to still have a leak around the clutch felt, but rest of the leaks are gone. :-)
Will keep an eye on it. Might even be that the oil I soaked the felt in overnight is pushing out and running down and that it will stop after the felt is rid of the extra.

I have another leak though, on the top, rear of the motor block where the two halves meet up, below the carbs. Never have had the bottom end apart...bit hesitant to do so as it is going fine and what with the good 110 thousand on it with never popping the thing open, I'm scared to pop it just for a small leak.

But...is there some trick to seal a small section of the gasket that just plain might have blown out there? I'm not careful about the wet sumping and the pressure in the sump must have blown the gasket a bit. Any tricks and ideas welcome...maybe some paste?
Thanks :-)
 
hehe, welcome to the world of oil weeping Commandos. The weep in seam under the carbs is the weakest place to get clamp force on and there is no gasket between engine cases so stuck with it till opening for a good gooping and a thread laid in. My Combat developed a leak there are about a year so may try to spray on a sealing goop I've seen ads for and Al pain over the evidence. I just tend to let the Amal dribble wash it off some, for a while.
 
Oh well...never having had it apart, wouldn't have a reason to know there is no gasket there. Guess the old fashioned gasket cement must be used for assembly, then. The "weep" is getting a bit bigger than it was...so eventually I gotta do something I'd think. Wait and see for now...works for me. Let me know about that spray please.

I fixed so many other small leaks that I'm mostly satisfied with the job. Had a crack in the back of the tank(interstate) and had to do the silver soldering thing. Tank empty, tank then full of water and in a large tub of water, leave small bubble of air at the point that needs to be heated...send the wife to the store for new shoes to keep her busy (works every time) ... and pray. Bought a couple of pairs of shoes over the years... so I know what I'm scared of. :roll: The burn marks in the paint are under the seat when it's mounted...so not too bad and it is not the original paint anyway. Main petcock washer and the petcock itself leaked too. Added a thin washer under the split ring on the petcock to add a bit of pressure to the seal and installed a new strange looking brass and rubber washer under the tightening nut on the petcock too and that is now dry...and new drain plug washers on the bowls too. Seems all dry now. Nice. Especially as the price of gasoline is now OVER ten dollars a gallon here. Costs a hundred to tank the car...and about 65 to tank the interstate, so when you have a drip...well , you figure out how fast you fix a leak here. LOL
 
This is a fix that may work until you open up the cases.

Clean off the leak area rear-real-real good. Acetone works good---use a stainless steel mini bruse to scrub-scrub scrub the joint----use air pressure to blow-blow blow the area. When you are confident that the area and the joint are as free of oil as possible----mix up some JB Weld and apply to the leak area---overlap the area a good 1/2 inch all around---make it about 1/8 inch thick over the leak area and taper off to make it look at least a bit cosmetically appealing. Then let it harden up real good.

Don't worry about the JB Weld---it will come off with a bit of work and a few beers when the time comes. This should keep it from leaking in the mean time.\

BUT----if there is another weak spot----you may have have another leak appear.
 
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