Ford 8N Front Mount Distributor Tabs Worn

I recently acquired a 1949 8N, front mount distributor, 6 volt positive ground. The previous owner was chasing a miss and was unable to find it. He replaced the plugs, wires, coil, battery, points and condenser, wiring harness, cap and rotor, ground (positive) strap, ballast resistor, rebuilt carb, new fuel bowl, cleaned gas tank and replaced all fuel screens. This tractor is running a 2N setup with the single pole generator and a cutout.

The tractor does run and will pull a brush hog, just not very well. Has a miss at all RPM, sounds like a John Deere at high RPM.

I checked the spark plugs. They are gaped correctly and are a dry, grey. I do not have a compression tester but I take this to mean compression isn't the issue.

I pulled the distributor and tried to verify his work. Points were gaped correctly. The mechanical advance weights were loose (could move axially along the shaft allowing them to get cocked) so I replaced the retaining c clips (which were MIA) and greased the slides. Bushings are good. Re-greased everything and reassembled.

I tried to re-time the distributor using an ohm meter to determine when the points opened. It seems I don't have enough travel in the mechanism to set it correctly. Off by 1/16" [u:ce7e6b9dbb]Is this common with cheaper points?[/u:ce7e6b9dbb]

Another thought; the tabs that drive the distributor are worn by 1/32 or so, on each of the driving faces. [u:ce7e6b9dbb]Is this normal?[/u:ce7e6b9dbb] I believe this is part of my difficulty in setting the timing.

The springs on the mechanical weights are not the same. [u:ce7e6b9dbb]Should there be two flat springs on each weight?[/u:ce7e6b9dbb] My assumption is there should be.

[u:ce7e6b9dbb]Is it normal to have to replace the main distributor shaft?[/u:ce7e6b9dbb] The bushings, and other surfaces seem to have no appreciable wear.

What is the distributor shaft material? Bronze right? I'm hoping there isn't wear on the cam itself.

Thanks for your help.

Wear on the distributor cam can make it difficult to correctly set the point gap. Correct point gap is 0.015". The distributor cam shaft is steel. The bushings are bronze. A replacement cam can be purchased through this site. They do wear out. I just had mine break a spring this past Friday. I've also seen one that was so worn, timing was impossible.

Bushing wear on the breaker plate or at the rear of the distributor, were the tang is, can also make it difficult to set timing.

Colin, MN
Replacement Cam

"Should there be two flat springs on each weight? "

Yes

" Is it normal to have to replace the main distributor shaft?"

No

" Off by 1/16" Is this common with cheaper points?"

Yes. It's also common with worn bushings. Telling us that " Bushings are good" and " The bushings, and other surfaces seem to have no appreciable wear." w/o measurements is meaningless.

Make sure your distributor isn?t worn out; check the wear parts with a micrometer and compare what you have to the factory specs (below)

Factory Specs:


Shaft top .4367 / .4370
Shaft Bottom .8625 / .8630
Cam Flats .789 / .791
Cam Lobes .869 / .871
Base Tang .177 / .178
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Thank you for listing the tolerances. I will be buying a new distributor.

Where is the best place to buy? This site, nnalert's, somewhere else? I want to buy the best product available.

I?ve been working on old cars, trucks & tractors now for over 50 years. Whenever possible, I get OEM component parts rebuilt. Given the high probability that any new component part purchased for an N tractor is made somewhere overseas w/o adequate quality control, chances are very good that you will be disappointed.

I'd just buy a used shaft & get the bushings replaced in the base & plate.

If you can't find a used shaft w/in specs, then get a new shaft from here, nnalert's or Dennis Carpenter & replace the bushings.

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/ @

Rod forest lake tractor 651 464 4628
75 Tips