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Discussion Starter · #1 ·
I could use your advice regarding motor alignment. I have a ADC 8" DC series motor and I am mating it to a transaxle with no clutch. Question is, how concentric must I get the two shafts? I only see a couple of videos online and it seems like everyone just uses a hand drill to make these adapter plates.

My adapter will be a 1-1/8" key shaft adapter welded to a splined shaft adapter that came with the car. The goal is to use a lathe to machine a concentric locater step in both pieces and then weld them together while in a vice.

Thanks in advance!
 

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Hi e,

I'm no expert on transmissions. But I think some, at least, depend on a pilot bearing in the crankshaft. I've never been sure how that enters into the mix.

When mating motors having 2 bearings to pumps or gearboxes also having 2 bearings, without a flexible coupling, dead nuts should be strived, but certainly within 0.005" TIR concentricity and 0.001"/" perpendicularly. A good resource is ANSI Y14.5 Standard for true positioning and tolerancing.

Hopefully you'll get a member chime in who has experience doing it with a tranny.

major
 

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Discussion Starter · #3 ·
I think those tolerances are a bit tighter than anyone could do by hand. I guess the best I can do is to measure things the best I can, draft it up, and then CNC cut it. The off center adapters don't seem to be good for much power and I can't find another way to do a clutchless coupler.
 

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Why are you posting the same question in different threads? For less confusion, you should stick to one thread. We need more info. Clutch, no clutch? Existing adapter plate(s)? Multi-view photos of all of the parts, including the transmission would be very helpful.
 

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Discussion Starter · #5 ·
Different questions, same theme. The goal is to get a new motor in this previously converted car but I need help.
 

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Discussion Starter · #7 ·
Looks like I found my alignment solution. Found the bolt pattern for the tranny!

http://www.super7thheaven.co.uk/images/YBEnginetoBellhousingBoltPattern.jpg

I have this drafted in cad and hope to have it cut this week, somehow. I was having troubes finding the face drawing for the ADC 8" motor so I'll just use my measurements to place the bolt holes. This should get my alignment pretty spot on.
 

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I was having troubes finding the face drawing for the ADC 8" motor so I'll just use my measurements to place the bolt holes. This should get my alignment pretty spot on.
Probably not close enough. As Major alludes to, lining up shafts with precision(at least by automotive standards) gears and bearings is no easy task. Ask yourself: why would OEMs go to all of the trouble and expense of carefully lining up and machining the ICE motor block and transmission bellhousing for precision fitting dowel pins(as most do), if attachment bolts alone were all that was necessary to do the job? Also, let's say you were lucky, by hit and miss, in properly lining up the shafts when putting the motor and trans. together. The next time, maybe you wouldn't be so lucky. Without the dowel pins, it's very difficult to properly line up the two.
 

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Discussion Starter · #9 ·
The google gods have heard my plea. I just found the motor dimensions! I'll use them for sure and get this thing centered properly.

I'll have to say, getting the specs and information on this project has been difficult. Is it because everything is advancing so fast?
 

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The google gods have heard my plea. I just found the motor dimensions! I'll use them for sure and get this thing centered properly.

I'll have to say, getting the specs and information on this project has been difficult. Is it because everything is advancing so fast?
OK, show us the dimensions and how you will use them to line things up.
 

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Discussion Starter · #13 ·
Alright, this is the best an electrical engineer can do. If you would like to review and provide feedback, that would be awesome!

I should probably verify the bolt sizes on the bell housing and then change the 11mm dia holes appropriately.
 

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OK, Mr. EE you've got your X axis dimensions, but no Y's. And, no dimensions at all for the motor flange overlay? The thing with the unthreaded bolt hole sizes is that they need to be oversized to accommodate the normal tolerances of typical bolts. Otherwise, threads won't start. You might get cross-threaded threads. A general PITA. Talk to your ME colleagues. Because of this need for oversized holes, bolts alone are a poor choice for precision alignment.

BTW the tolerances on the Cosworth engine flange hole placment drawing are +/- 0.01mm. Much tighter than misalignment limits that Major and I call for.
 

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Discussion Starter · #15 ·
Can I not use the bolt shank to align plate to the bell housing and the plate to the motor? The bolts the previous owner used had no shank and the plate was a bit sloppy. Probably why the old motor appears to have a burnt up bearing...

I have a couple of people I can ask to verify the bolt holes. This bell housing does not appear to have any alignment pins so bolts is all I have. I used a chart to determine the bolt holes for the 3/8" bolts (0.406 - 0.416" so I used the smaller size).
 

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Can I not use the bolt shank to align plate to the bell housing and the plate to the motor? The bolts the previous owner used had no shank and the plate was a bit sloppy. Probably why the old motor appears to have a burnt up bearing...
Ok, you just answered your own question! Looking at the engine flange drawing. Near the bottom are holes "C". These are counterbored("c'bored") to 11.5mm. These are probably machined for hollow dowels (the mounting bolts go through them) for precision alignment. Talk to your machinist about using dowels in these holes. Since you're going to all of the work of CNCing a plate(s), using the dowels will save you a lot of trouble in the long run!
 

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Discussion Starter · #17 ·
Thanks for notocong that! Maybe they took the pins out during the POs conversion, they are not currently there. I can sure add them in!

For full transparency, this plate will be cut with laser and I'll probably use 1/4" steel (maybe stainless). The dimensions are only for reference as the dxf will be converted to a gbr file and then fed to the laser cutter. :)
 

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This bell housing does not appear to have any alignment pins so bolts is all I have. I used a chart to determine the bolt holes for the 3/8" bolts (0.406 - 0.416" so I used the smaller size).
Here's the hollow dowels in the engine block:http://www.mwstewart.co.uk/images/cars/Ford/mk3frstrestoration/red_frst_12.jpg
AIR the dowels are a tight fit in the block and a slip fit in the transmission.

This is at trip down memory lane. I did a lot of work on this family of engines 30+ years ago.
 

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Discussion Starter · #19 ·
Thanks for the photo, that really helps. I was wondering how they bolted this thing in. I hope none of the tranny threads are stripped, but I think the bottom holes might be.

I'll have to look through and see if the newer transmissions bolt up to this car as well. Being that this one is 38 years old, upgrading might be worth it. Sure would be fun to put a "modern" powerplant from a 1990's Escort, but I think this electric conversion will still be a good time.
 

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Discussion Starter · #20 ·
Got my pieces today! Thought I would share.

10awg mild steel CNC laser cut using the drawing I had uploaded previously. Everything fits really snug so hopefully I nailed this concentric shaft thing.
 

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