Mechanical Advance distributor Identification help

Busmoss

Busmoss

Member
I am new to Model A and B components. Unfortunately for me this distributor data plate has come off and I cant tell what I have here. I see the timing plate says autolite. The back lash and advance springs are so weak that the timing is all over the place. Is this worth fixing?
It is unorthodox, I know, and I have ordered an original manual set up. Could this style even be concidered good for an emergency spare if repaired?
Attached photos:
 

Attachments

  • IMG_0478.jpg
    IMG_0478.jpg
    41.9 KB · Views: 158
  • IMG_0479.jpg
    IMG_0479.jpg
    43.1 KB · Views: 136
  • IMG_0480.jpg
    IMG_0480.jpg
    39.3 KB · Views: 145
  • IMG_0481.jpg
    IMG_0481.jpg
    38.5 KB · Views: 127
Looks like a Jeep distributor, here is a picture of one I converted.
 

Attachments

  • Jeep-dist.JPG
    Jeep-dist.JPG
    107.9 KB · Views: 84
Thank you Bob C for sending me down the right path! Using your lead I found another thread and some information talking about 50's Jeep CJ5 Both for A and T. Not that crazy of a thing after all but a curve ball for a new owner non the less!
 
New member here so I am going to go on ranting:

I like stock parts and being able to experience the now unique task of manipulating the timing while under way. I also like the idea of being able to cold crank the engine closer to TDC. However, my model B engine and set up was to be a driver car. This is a serious hobby for me and I want to drive A LOT of miles once sorted.
The Jeep mechanical distributor pictured above still seems to be a viable option. The Model A aftermarket mechanical distributors are available to order at a reasonable price. Who doesn't like options though? I just looked at a complete replacement distributor for the Jeep and it is $135 including cap etc. Could be cost savings at play here.
I am not afraid to tinker in fact I have already cast my own aluminum water pump impeller and machined new starter bushings from scratch.
I think once I have the standard part here I might rebuild this old Jeep part for fun.
 
I'm running a willys jeep distributor on my B engine and I love the way it performs. I made a timing degree marker behind the pulley and I can time it with my timing light.
 

Attachments

  • ls head on 2.jpg
    ls head on 2.jpg
    80.7 KB · Views: 94
31steve, What advance range should one expect? Static timing degree target? I was messing with that Willys Jeep distributor today because I cant help myself. I shortened the stretched advance springs by one coil and took out the slop but have certainly changed the advance curve.
Marked my crank pulley 0, 19, and 40. Set the points to just open @19 with a buzz box as if it were a "B" distributor. It ran quite nice but if I had a closer to TDC it would probably start with less throttle.
 
Busmoss, It's been a while since I set it and I will check next time I get my light out, but I think I set it at 20 degrees and it advances to 32 to 35 range. I could have set the advance higher but wanted it to start easy.
 
The amount of advance can vary with the load, rpm, and compression ratio and other factors. There is knee in the advance curve were retarding will decrease the performance and advancing will have no effect. An experienced Model A driver will instinctively adjust the advance for different loads and rpms, and perhaps the GAV too. More modern distributors had combined centrifugal and vacuum advance to adjust for load and rpm. The modern cars have a computer that does all the thinking for you.

Too much advance can ruin the rod bearings in short order and have other detrimental effects. I like the manual distributor because that is what I am used to after 60 years of driving Model A's and I like being able to adjust the advance according to conditions.
 
With a low compression head you can advance the spark quite a bit for much better performance so long as it doesn't ping. The B engines had, I think, 19 degrees advance to start with, so long as you don't crank it by hand and risk a backfire. The spark should advance quickly as it is a low revving engine.
 
31steve said:
Busmoss, It's been a while since I set it and I will check next time I get my light out, but I think I set it at 20 degrees and it advances to 32 to 35 range. I could have set the advance higher but wanted it to start easy.
Click to expand...


Steve have you had a chance to survey the Jeep Distributor timing /curve? Can you advise a model number or Jeep vintage you modified from?


Matt
 
You must log in or register to reply here.
Back
Top