Overdrive

The 1930 Model A purchased recently has an overdrive or gear splitter with the following identification; Ahlberg Co, Culver City, Cal. I am looking for anyone who may have knowledge of this equipment?
 
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In the model T era there were no less than 31 different auxiliary transmissions made for them due to the nature of the 2-speed planetary transmissions limitations. The model A trans was better but there have been a lot of overdrive set ups both in the early era and the modern era. There isn't much info about Ahlberg Company out there on the net so it's likely an old early era aux trans set up. Auxiliary transmissions could be overdrive, underdrive, or a combination of the two. It would be interesting to know how it's made.
 
I spent some time looking for information on Ahlberg Co.

Culver City was founded in 1917 primarily to service the motion picture industry.

Ahlberg existed as an "offshore" producer of many industrial parts, including automotive.

Their existence as anything but a storefront selling auto parts in Culver City is doubtful - or anyone for that matter. Culver City was not where you went looking to modify your car.

Not that it didn't exist - it obviously did at least once.

Joe K
 
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Here are some pictures. Thank you for your interest in helping?
 
I would like to see a pic of how it is connected to the trans. Looks like they got rid of the torque tube and have an open drive shaft.
 
Now that's a completely new one on me.There were probably quite a few manufacturers of that kind of thing years ago that never made more than a handful.There is probably somebody,somewhere,that either has one or knows something about them.Ask in every possible place you can,you might shake somebody out of the woodwork.The only place I've ever seen that name before is on antique cameras.
 
Interesting vent setup tying the unit and the rear end together.Looks like they cut down a stock torque tube to build the unit,it still has the original speedo drive in it,and has the speedo re-hooked to the unit itself.
 
Yes, the problem I am having, is fluid from the overdrive is getting into the banjo, causing it to be over full and then leaking through the axel to the rear brake drums. Unless I find someone knowledgeable about this setup, I will probably switch to the original setup since I have a torque tube and drive shaft off another car I put a Mitchell in.
 
The original setup wasn't really properly vented,the pressure just kind of escaped up the torque tube,through the trans,and out the shft tower vent.With that OD unit in there that path is blocked off.The OD unit looked like it was originally vented,and somebody added the vent to the rear end,but tied them together.There may be a vent to the atmosphere but it isn't in the pictures.If that whole rear is sealed up oil can be forced out of the seals somewhere.That oil in the OD may be forced under pressure into the rear end.Then again there may be a bad seal in the rear of that OD unit.Old seals crumble with age,if you are planning to take it apart anyway you will see if the seals are bad.If that rear isn't vented to the atmosphere somewhere I would take that jumper pipe off and vent both parts to the open air.Then see if the same thing happens.
 
The original setup wasn't really properly vented,the pressure just kind of escaped up the torque tube,through the trans,and out the shft tower vent.With that OD unit in there that path is blocked off.The OD unit looked like it was originally vented,and somebody added the vent to the rear end,but tied them together.There may be a vent to the atmosphere but it isn't in the pictures.If that whole rear is sealed up oil can be forced out of the seals somewhere.That oil in the OD may be forced under pressure into the rear end.Then again there may be a bad seal in the rear of that OD unit.Old seals crumble with age,if you are planning to take it apart anyway you will see if the seals are bad.If that rear isn't vented to the atmosphere somewhere I would take that jumper pipe off and vent both parts to the open air.Then see if the same thing happens.

What Keith says. I had to add a vent to my Rear End when I installed my Mitchell O/D. It started building pressure and weeping a little oil. You can see I also added copper washers à la Ford 9" to the banjo bolts in an attempt to control seepage thru the threads.

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One thing I can tell you for sure, venting the rear end thru one of the banjo bolts like in jlking2010's picture (post #8) is the wrong place to connect a vent. My first attempt to vent my rear end after installing my Mitchell was in that exact same place and the turning ring gear pumped oil all over the bottom of my car.
 
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Ahlberg existed as an "offshore" producer of many industrial parts, including automotive.

Their existence as anything but a storefront selling auto parts in Culver City is doubtful - or anyone for that matter. Culver City was not where you went looking to modify your car.

You're probably confusing this company with Ahlberg Bearing.

Ahlberg Co. manufactured transmissions and small engines at their Culver City factory during the late '20s and early '30s. I've found references to this factory from 1928 to 1932. Ahlberg was Karl E. Ahlberg; he has a patent for a fluid pump filed in 1929 from Culver City.

(Attached screenshot is from 1926.)

That overdrive may be period correct.
 

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