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MG MGB Technical - about to install new transmission in car

Just bought an overdrive trans for my 74 B. I planning on installint it next weekend. any advise on what should be ordered prior to install so I don't have to be held up? ie: new engine mounts, new clutch, new bolts etc....
Thomas Strombeck

I heard of someone who pulled his engine, installed the transmission/overdrive, re-installed the motor only to find that the O/D had serious faults --- had to pull the engine again, etc.

I had an expert inspect/overhaul my O/D before installation. Several seals, etc. needed replacement.
Dan

The best route is to think of everything that you replace while the engine and tranny is out and take care of it. Engine mounts, clutch, pilot bushing, rear oil seal, tranny mounts, clutch hose, exhaust, U joints, perhaps a little refreshing of the engine bay paint...now is the time to do it. Check the new tranny and make sure its in good shape. Replace the front seal, connect the OD solenoid to 12V to make sure it works.
william fox

If you have access to a spare flywheel, have the mating surface machined. While it won't improve performance (unless the old flywheel was in really bad shape) it will help extend clutch life and will improve initial engagement.
Mark Childers

Thomas-
Williams suggestions are excellent. By all means, checking the solenoid on the overdrive to be sure that it's functioning is essential. Also, remove the side cover plate of the overdrive and clean the filter, inspect the pump and the valve mechanisms. Replace the O-Rings as well. Mark's suggestion of having the flywheel trued is good, too. If the clutch has seen better days you might want to consider using the Driven Plate from a Triumph TR7. Its splines are identical with those of the original, thus it will fit without modification. Having been designed to be used with a more powerful engine, its greater surface area will ensure all of the grip that you will need. When used in stock engines they tend to last 140,000 miles, which is considerably better than the 80,000 mile life expectancy of the Original Equipment clutch. When you go to reinstall the engine/transmission package into the car, install the rear crossmember onto the rear of the transmission before you try to put it back into the car. Leave all of the crossmember bolts loose. This will make putting it all back together under the car much, much easier.
Steve S.

...and renew the engine rear main seal!

Costs less than $10 - and it'll save you grief from oil leaking there.
Daniel Wong

#1 Don't replace rear engine seal unless it's leaking or out. NEW ONE WILL LEAK WORSE. Don't surface flywheel unless you balance. Engine will vibrate. BEEN DOING THIS TO LONG. MURPHY HAS GOTTEN ME TO MANY TIMES. Who ever said (my parents) do it right the firsty time (bobby) and you won't have to do it over did not live in my world!!! Bob Thompson
Bob Thompson

Thomas,
If you have an engine hoist it is really not a tough job. I did the swap a couple months back and did it with jack and a two stands. That was a pain. You can pull the engine with most of the stuff still on it. I'd check the mounts while it is out, but if there good, don't replace them it's a waste. The one thing I would definatelly do it modify the transmission mounts. They are designed like sh*t and there are articles in the archives to easily modify them to make re-assembly easier. The one thing you do want to check on the OD are the 2/3 switches on the top. These are impossible to reach once the tranny is in. There pretty straigh forward, you have on reverse light switch, one OD lock-out switch, and some OD's have a 3rd switch that does something??? with the seat belt system???(would not worry about that one). They are easy to check with a voltmeter. I'd look the clutch over, but if it looks like it's got some good life left in it, i'd leave it as if you change it you have to re-align it, check the throw out bearing too. Mine was shot, but the clutch was good. If you don't you just slide the old tranny on and the new one off.
There are something like 5?? or so o-rings for the OD unit, I'd order them and also a new steel ball that sits on top of the solenoid. They are all cheap. You also want to check the filling method of the OD. Some are side fill others are top fill. Side fill you can do from underneath, if it is a top fill make sure you have the hole on the passanger side behind the center console or your SOL. I think the top fill was like early 70's and the side fill was later 70's??? Be good to clean the drain for the heater box too. It's a stupid looking ball thing that hangs above the tranny. There is a slit in the bottom and you just open it up and dump out the leaves ect...
When I did mine I pulled it out, put the wiring in, then re-installed. You might want to check your u-joints as you'll have to disconnect one end of it anyway and it would be easy to put a new one in if needed. After installation I wired it up, topped it off and went for a drive. I think it's good to get a feel for it before you start tearing it appart. After several miles I replaced the seals, changed oil ect..
Other things to check might be the hoses and belts as you'll have the engine out and the engine seals(exterior) as any oil leaks will be more evident if it is out. Also you need a longer speedo cable.
Hope this helps, kinda rambled a little. If you have any specific questions e-mail me at john_arthurs@yahoo.com. Job is still very fresh in my mind.
J Arthurs

Just make sure you connect all the electrical harnesses before bolting the rear tranny member!
Luis

This thread was discussed between 31/08/2002 and 05/09/2002

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