MG MGB and MGB GT Tech Talk
I've been reading the debate on the topic for the last hour after doing a search.
I've replaced just the transmission on my TR3 but that was easy as the transmission tunnel bolts out.
WITHOUT rekindling the debate, could someone who is familiar with taking out just the transmission please offer some play by play.
Thanks
Sorry Albert, I personally cannot see any advantage in trying that shell game. It is far to easy to yank the engine and transmission as a unit to even consider trying to wriggle the transmission out in some way or another.
Debate all you like, but having done countless engine ectomies I can't see the rational in doing it the other way.
Jack
Don't even think about it. It's possible to change a clutch without pulling the engine, but it is easier to pull whole lump.
I tried it. Bolted it all back together. Then took it all out through the engine bay. I think it could be done as a trans only, but it seems like it's easier just to pull it all out together.
The TR has a pretty wide frame at that point and the entire tunnel is fiberboard so when you remove it there's this huge hole you can pull the trans up thru.
No such thing on the B. That area is all structural metal. So it has to come backwards quite a bit and down, all the while twisted about 45 degrees to the right to clear the starter "bump". THEN it has to be dropped at the front and re-twisted and extracted frontwards to get it out of the un-removable cross member. Putting it back in would be even worse since you would also have to align the input shaft with the pilot bearing and all that involves.
All of which, done flat on your back under the car by your lonesome (no room for any extra hands) and the puppy weighs way more than you imagined 70 pounds (or so) could weigh when you started out. So, unless you are, from flat on your back, personally able to lift your car onto a pair of 17" high jackstands [u]without[/u] a jack I think you'll have an impossible time removing the trans without pulling the engine.
I have seen a competition B modified to make this operation simpler (bulging the firewall opening and re-fabbing the rear cross member to a bolt-in configuration, etc. ) together with a custom trans jack saddle that made this work reasonably well (or so i was told at the time).
Albert having earned the t-shirt on this job here is the condensed version
unhook battery
drain trans
remove drive shaft
unhook elec harness
remove slave
remove shifter
support engine and trans with jacks
remove crosmember
remove starter
remove engine trans bolts
rotate trans clockwise enough to remove shifter housing bolts
remove shifter housing
rotate trans to where starter bulge is down
slide trans back off clutch and drop the front and wiggle out.
Replacement is the reverse
Now you know why everyone just pulls the entire unit. The trick is the removal of the shifter housing to allow room to slide the tranny back far enough. Then you have to get the shift forks lined up blind when it's replaced. And all the oil you get on yourself no matter how long you've drained the unit. I'd much rather pull motor and trans.
Forget about it if it's an overdrive.
Bill
Bill, you forgot two steps.
Several extra hours in the shower trying to get the oil off your skin and several extra PBR breaks to relieve the stress of getting the shift tower off and especially back on.
A trip or two to the confessional will be needed when it is all over. LOL
Jack
Have owned my 65 since 1970. Pulled only the tranny only once - never again.
Pulled both MANY times.
Don't even bother trying to pull just the tranny.
If nothing else, that gives you the ability to clean up the engine bay and engine!
I get the picture.
In reading past posts there was never really enough detail to grasp just how hard the "transmission only" approach was.
That's exactly why I brought the issue before the board...and the accumulated wisdom there in.
THANKS, guys.
Albert this is a step by step description that I found several years ago, but I've never been brave enough to try it.
http://www.theautoist.com/pulltranny.htm
Take the gearbox out by itself....cut out the stupid fixed crossmember and make a bracket to replace it.
Its a sensible modification for the years ahead and plenty of us have done it (see previous posts).
Paul ;-)
Obviously the biggest problem with MGs is that they were not designed in New Zealand !!
I don't see the big deal, sitting trans and engine in the shop floor is 1.5 hour job for a good line mechanic, and maybe a half day job for a amatuer. Also, how many times would you need to just remove a transmission on a MGB for whatever service, it nots like you want to do a clutch job this way, unless you're doing it half ass, not like you would want to remove a flywheel for surfacing or replace a pilot bushing with the engine in the chassis, but what do I know, I'm a bench builder :)
Yes. The motor has to come out. Not a big deal
Most people here remove the motor and trans together.
I have only seen it done by pulling the motor, lifting up the car and letting the trans out the bottom. To me this seems easier. Takes my mechanic about 45 minutes to have the motor out on the floor and about 10 more to have the trans on the floor after that. It is amazing watching a pro do it. It is like magic. I know it would probably take me a week to do it myself.. LOL
Either way, The motor has to come out.
here is some pics of the motor and trans coming out of my B
http://www.seeberg.com/mgb/engine/engine3/
and doing the clutch on the GT http://www.seeberg.com/mgb/gt/clutch/index.html
It seems like a lot of extra work to get the motor and trans out together. 6 bolts and the starter, the engine is free. Yank it, support the trans, lower the trans( lift the car). done.
Just wanted to throw in there is another way than pulling the entire wad out in one shot.