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Adding OD to my '67

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vping

vping

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As ya'll may know my car is a '67 GT https://s70.photobucket.com/albums/i87/vping/1967%20MG%20BGT/ but recently I picked up a '74 GT that happened to have OD. I am slowly coming to the realization that the '74 https://s70.photobucket.com/albums/i87/vping/1974%20MG%20BGT/ might be beyond repair. So I in turn have an entire car's worth of parts and this OD unit.

My '67 currently has a '68 trans in it so the tunnel has been "banged out" to accomodate.

What else might I need to do to put this in. The OD is a black lable laycock overdrive.

11-19-06-ODPlaterust002.jpg


The '74 has 42,000 documented miles on it driven by the original little old lady owner until she gave it to me.
 
I have a '72 OD unit in my 67. The previous owner did the installation, but if I can be of help let me know. If your '67 is early, you won't need the reversing lamp switch.
 
There is one tidbit. Yes it is early and does not have reverse lights. One less thing to worry about.
 
Tony--This is the type of OD I have in the Red Bull. (see previous posted picture) /ubbthreads/images/graemlins/driving.gif
 
WOO-HOO!!!
 
SOOOOooo, This is a good thing? I will probably need advice on hooking up the trans when time comes.
 
I guess this will be as easy as pulling the motor & tans and swapping it out. Should I do anything to the OD before I put it in? How can I check it for proper operation?
 
Steve_S said:
If you wanna sell that reversing switch let me know. <img src="/ubbthreads/images/graemlins/wink.gif" alt="" />
Click to expand...

If & when I figure out and am able to get to it, I will get in touch with you about the switch.
 
Unless you rebuild the transmission, you're taking a gamble. It may be fine as is, but then again it may not be. Good luck whichever way you go!
 
So I should pull the '74 and have it re-built. What might that run me?
 
It ain't cheap. That's the only reason I'm not telling you to rebuild it regardless. Sometimes it works out fine, and sometimes a problem develops and you have to pull it all out again to rebuild. Then again, sometimes a fresh rebuild develops a problem. I'd try to determine the condition of the gearbox. If it looks fresh then it may be worth a chance.
 
For all the hassle of installing, I'd make sure its operational & problem-free before installing...
 
You'll need a new speedo cable, some sort of switch and wiring harness to activate the OD (probably can use parts from donor car) I think the driveshaft is the same. You can check by measuring standard 4 speed from bell housing to tail shaft and comparing to the OD unit. You also have a driveshaft in the donor car. I'm pretty sure everythin else lines up.
 
Is there a way to visually bench inspect a trans? I thought about getting the donor car running but then the hassle of doing that is.....
 
Electric motor with a pulley..another pulley on end of trans...hold trans down on table with some type strapping...fire up electric motor...get trans turning to speed, turn off motor, engage clutch, shift, turn on motor
 
I understand the pulley on the front. What it the rear pulley for. Watching?
 
vping said:
I understand the pulley on the front. What it the rear pulley for. Watching?
Click to expand...

1. a pulley on front of electric motor.
2. a pulley on front of gearbox (first motion shaft) would be ideal. You may need to use the tailshaft flange instead, as I seem to recall the FMS is inside the bellhousing.
3. v-belt arrangement to connect them.

Some other random thoughts...

Align *very* carefully. Watch the pulley ratios. Make certain you're spinning it in the right direction. Fill box with new oil. An old 3450RPM motor (like from a washing machine or somesuch) with a 1:1 ratio should be just fine. Probably needs to be a couple of HP to spin it fast enough for the OD to pump up

I looked into having https://www.emachineshop.com make up the rear pulley in aluminum, but never finished the drawing. It would be pretty simple.
 
I'm gonna stick my nose in here and offer up an opinion... Without doing a full tear-down and visual inspection you're chancing that:

A) It may be fine.
B) It may be "half-fine" and work for a while.
C) It may be in need of work now that will break more $$ bits with first torque applied.

With only three possibles, I'd take it apart and find out on a bench rather than after it's in the car. You've a 33.333% chance it'll work correctly for any length of time. At the very least you'll be able to renew the layshaft, bearings & seals and KNOW what it's got. Do the second gear baulk ring while in there. The O/D can be cleaned well, O-rings & check balls renewed.

It's WINTER, Vince! ...but half-over now so ya better get to stitchin'! /bcforum/images/%%GRAEMLIN_URL%%/grin.gif
 
You know my MO. Can I do this myself?
You also know if I pull my motor I might want to "do stuff" to it while it's out, won't I?(please say no, please say no, please say no)
 
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