Front Mount distributor rebuild

[greywolf224]

Rebuilding a front mount. When I took it apart, there was grease pretty much splattered everywhere.

I am thinking to use carb cleaner on the break plate assy and the cam weight assy to get all grease off.

When putting back together do I need to put any special lube on the upper and lower shaft bushings or on any part of the cam weight assy?
I'm thinking that the only lube needed would be for the shaft lobes that the rubbing arm rides on?

 

[gears]

When I did mine I lightly greases it (lithium) - make sure the oil grooves are clean (mine were baked with crud).

 

[Bruce (VA)]

Carb cleaner will work fine. You don't have a fiber washer to worry about!

You are replacing the bushings, right?

Make sure the oil ports & grooves are clear.

As to grease.....

Any grease, no matter how good, will dry up w/ age. Same w/ cold weather; grease gets stiff.

I spray WD40 on the weights and shaft ends, then let the tractor lube system take over.

Of course, you need to lube the cam for the points rubbing block.

Distributor cam lube:

http://www.napaonline.com/Catalog/Result.aspx?Ntt=ECH+ML1&Ntk=Keyword&Nty=1&Dn=0&D=ECH+ML1&Dk=1&Dp=3&N=0

Distributor cam lube
http://www.carquest.com/webapp/wcs/stores/servlet/subcategory__10151_-1_10651_11340
75 Tips

 

[greywolf224]

Thanks

You are replacing the bushings, right?

I was hoping that I did not have to since the press I have is old, very large and not 100% true but when I disassembled there was too much shaft play so I have no choice.

I spray WD40 on the weights and shaft ends, then let the tractor lube system take over.

How much oil does actually get draw up? Cant think its much since it would splash every where in the housing.

Bruce here is a pict of the bushing in the plate assy. The bushing housing seems chewed up. Is this normal?
I could only think that the PO did a lousy bushing job since the rotor is plastic and would disintegrate if they rubbed.

 

[Bruce (VA)]

" I could only think that the PO did a lousy bushing job "

Probably. But I wouldn't use that plate. If they bent the tower, you will soon eat up the new bushings.

I do not like the new plates. And others around here have the same conclusion.

These guys should be able to help you w/ used parts:

John Smith smith8NATatt.net

Rod Mondor fltractorATpeoplepc.com

Replace the AT in the address w/ @

You may need to replace the fiber washer on a new plate. And perhaps the bushing unless the vendor already has.

There are three ways to replace the bushings in a front distributor:

1. Buy new bushings (part numbers 9N12120 front & 18-12132 rear). Press out the old ones, press in the new ones and ream to fit. CAUTION: do not try this unless you have a press & know how to use it. If you break the base, a new one costs $130. If you bend the tower which holds the front bushing, a new plate will cost you $30.

2. Take the new bushings and distributor to your local machine shop.

3. Send the distributor out for bushing replacement if you do not have a local machine shop.

Make sure your distributor isn’t worn out; check the wear parts with a micrometer and compare what you have to the factory specs.

Factory Specs:

Shaft top .4367 / .4370
Shaft Bottom .8625 / .8630
Cam Flats .789 / .791
Cam Lobes .869 / .871
Base Tang .177 / .178


" How much oil does actually get draw up?"

Not much. It doesn't need much because the bushing is sintered. And, depending on the model of your distributor, it probably has an oil wick in the shaft.
75 Tips

 

[greywolf224]

TX for the info.

 

[John Smith8N]

That's a cheap aftermarket plate, not original. That chewed up top is how they manufactured it when new. They're not real big on quality where that one came from. Lots of those are out there now.

 

[greywolf224]

John TX now I know. Do you have an original that you can part with?
Much appreciated.

 

[John Smith8N]

(quoted from post at 17:41:38 02/01/15)
John TX now I know. Do you have an original that you can part with?
Much appreciated.

Not at this time. Sorry.

 

[greywolf224]

You may need to replace the fiber washer on a new plate. And perhaps the bushing unless the vendor already has

Bruce you make mention of a fiber washer. By this do you mean the plastic nut that the primary contact screw screws into?

Also was able to find an after market breaker plate that looks to be designed much better around the bushing than the other after market plate I had. Thoughts???

 

[Bruce (VA)]

The correct name is the fiber insulator, but being a FOG, I call it a washer.

Yes, the plastic nut replaces the fiber insulator.

Plate looks better. Hope it fits ok.

Too bad the brass screw isn't concave. I've got a few around here of various sizes that I was going to try & drill out. Haven't got to it yet.

 

[greywolf224]

Let you know as soon as I get it.
What got me interested in the plate is the different mount for the bushing. Just seems stronger.

Got a few concave brass screws saved away so It will be the first thing that I change.

 

[John Smith8N]

(quoted from post at 23:36:27 02/02/15)

You may need to replace the fiber washer on a new plate. And perhaps the bushing unless the vendor already has

Bruce you make mention of a fiber washer. By this do you mean the plastic nut that the primary contact screw screws into?

Also was able to find an after market breaker plate that looks to be designed much better around the bushing than the other after market plate I had. Thoughts???

I haven't seen that one before. It appears to be cast or molded all one piece from pot metal. Hopefully the points mounting screw threads will hold up and not strip easily.

 

[greywolf224]

John I can only hope.
Here is the back side.

 

[gears]

I bought that same one from Just and was pleased with the casting. I did find that I had to bend the points a bit so they'd line-up square and still have some adjustment.

 

[greywolf224]

Good to hear. Am guessing the points are as cheap as they come. Quality set of points cost about 2/3 the price of the whole plate assy.