Been plugging away with restoring this unit.
Fighting rust. Use navel jelly.
Big box of service parts
The Drive:
I needed to go though the bottom drive unit to make sure everything was okay. Other then a bearing that needs to lube and running all was good.
This is the part of the drive that is bolted to the crank. It basically takes the place of the mechanical advance and points. Many of these units have lost the drive gear for some reason.
No one has been able to come up with a source for these gears either. The base would not be that hard to make on a lathe, but the gear is another matter.
The gear sits on the drive and is held in place with a simple key way. The outer "plug" threads onto the crank and holds everything in place.
There is a pin on the backside of the drive that slides into a hole on the crank. This locks everything in place and also provides a way to time the whole set up.
RC placed some timing marks on the drive that can be seen through a window on the unit.
There is a single bolt that goes up through the bottom and holds the second gear in place.
A small plate keeps everything sealed. Everyone that I have ever had just used some silicone or liquid gasket maker. Im not a huge fan of that. Might sit one day and hand cut some gaskets for this.
Have some material at work that could do the trick.
You can see that there is a bearing in the gear. Would have liked to replaced this, but there are no numbers on the outside and since it is stacked in I fear removing it.
On the back side of the unit there is an oil seal. This seals around the drive gear. On a CB750 this isnt a super oil wet cavity, but I would like to replace the seal.
Will have to look into what a 11730 oil seal is and were to get some.
Distributor:
Still have not gotten the advancer parts to the point that I am happy with them so this unit has not been finished yet.
Wires were to far gone to bother keeping. Will have to find some replacements.
Unit has a chunk missing out of the base. Less then thrilled about this. But in reality you cant see it nor does it effect function. Ill build a bridge and get over it.
New Mallory points mounted onto the new Mallory points plate
Have a bunch of bushing bearings for the advancer weights after I am happy with how they cleaned up.
Interesting piece here. Seems that this plate is reversible based on rotation. I did read once that people were able to take a stock VW unit and reverse the direction, but this required cutting, welding and a fair bit of work.
Wonder if this plate is the key to all that? So far I have not been able to find ANY information about it based on the numbers stamped into it. I am going to reach out to Mallory about it latter.
Stupid question to follow......
Is there any "timing" or anything that needs care with this piece? It holds the lubes to the plate. I didnt see any marks and cant see how it would matter.
Oh and solved the great 320 Vs 320M debated in regards to the rotors.
The M supersedes the non M rotor and seems that the only difference is a screw Vs a rivet holding the metal on.
Both are 100% interchangeable. Nice to know as the non M rotors seem to show up cheaper NOS.
Things to still do:
1 - Find main oil seal
2 - Finish rebuilding advance parts
3 - Research LH/RH plate
4 - Make final parts list of items used.
5 - Talk to Mallory
Was able to order the parts to rebuild both of my units and still have some parts left over.
Also have found some "rebuild" kits that seem to include the advancer weights. They are listed for 8 cylinder applications though. Anyone know what actually changes from 4-6-8 cylinder units? Cant see why the weights would be any different. I think mine will clean up well enough to use, but would like to track down as many parts and as much information as I can about these set ups.
