MG-Cars.net

Welcome to our resource for MG Car Information.

Recommendations

Parts

MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG MGB Technical - Is it possible to remove gearbox with but not eng

On a 71 BGT, is it possible to remove gearbox without removing the engine. My father's B has a bad throwout bearing (with less than 2,000 miles on it, and I need to replace that and check on the new clutch and pressure plate.

Just hate to pull the engine again if I can avoid it. Will the gearbox slide back far enough once the crossmember support is removed?

Thanks,
Jeff
J Delk

Simple answer is "No".
Derek Nicholson

I have NEVER tried this, but...

http://www.theautoist.com/pulltranny.htm
...

The answer is Yes only if the gearbox has not got overdrive and you take off the gearlever turret.
Chris at Octarine Services

Derek
The simple answer is you gotta be brave and inventive, but I've never tired it.
Hey where are you hiding out these days my friend ??
Gil
Gil Price

If you have had the engine out recently (and it sounds like you have), then I suspect you'll be far quicker taking the engine out than messing about trying to do it from underneath. I have had the engine out 4 or 5 times and can do it in just over 2 hours from running (leaving box in car). The first time was the slowest because i didn't know what I was doing, but also some nuts hadn't been loosened for many many years!

Have fun
Iain
67 BGT
I D Cameron

I would never argue with Chris, but experience is a big factor here, and Chris has more than most of us will ever have. I'm with Iain, and I think you will have a much better time of it if you do the work on the engine on the bench, then do it from underneath with the gearbox out. It's an adventure, right?

warmly,
dave
Dave Braun

Dave,

I don't think Chris is suggesting it is the best way. I am pretty sure he always pulls an engine to change a clutch. I think he is simply answering the question. It is possible, but is it advisable?

Iain
I D Cameron

I'll bow to Chris's longer experience. First time I can recall anyone saying yes to this question.
Derek Nicholson

Thanks guys. You all are telling me what I think I already knew - I'll treat it as an adventure and go from there! I just hate doing it again to replace a failed part - but that is part of it.

Best regards,

Jeff
J Delk

It can be done, but to me it is easier to just pull the whole thing. If the car has OD then you will have to pull the engine/tranny as a unit the tranny is longer. If non OD it is just possible to do it. The problem is the second crossmember or brace that is just before the end of the tranny. There will not be room to go forward and back. With shift lever and turret removed JUST enough room. I have seen several cars that have had the brace removed or cut. Not really a good idea as it is structrual. It is also much easier to put the tranny and engine back togather on the ground vice getting it aligned in the car.

HTH

Ron
Ron Smith

Even if you managed to change the thrust (throwout) bearing this way if you want to check the pressure plate and clutch also you'd likely run into alignment problems and it would all end up as a frustrating waste of time, bite the bullet and pull the whole thing out. As someone else has said, with the right gear it's only an couple of hours work either way.

I have the same problem with my 68 GT incidentally and will be replacing the old carbon bearing for a roller type when I get round to it.
Ernie York

Here's a quick and dirty method taught to me by an old timer. Bore a hole about 1.5" in the bell housing and remove the bolts that mount the pressure plate to the flywheel through the hole. The transmission only has to be moved back about an inch to clear the input shaft from the pilot bushing and can be manuvered free from there, with the clutch asembly hanging on the input shaft. To reassemble, install the throwout bearing then slide the pressure plate and disc onto the input shaft and put the trans back in place. Leave about a 1/2" gap between the bell housing and engine and use a long screwdriver to push the pressure plate into place to get the first bolts started then work your way around once to install the bolts and once more to torque them. When you're done use a plastic plug from the hardware store to fill the hole.
It ain't pretty but it works.
Bill Boorse

Wow, it is completely astonishing that someone would think of that! I decided not to do it right about when I read "bore a 1.5-inch hole in the bellhousing" but still... you gotta give the guy props for thinking that up!
Sam

Back in the late 80s when I first started playing with MGs nobody told me it wasn't possible to remove an OD gearbox from underneath the car so I went ahead and did it, however, to do it you have to remove the radiator( on a CB car), undo the engine mounts and slide the engine forwards.

I would never do it again, serious pain in the rear!

If you really didn't want to pull the engine it may be possible to slide the gearbox back just enough that you cab get your hand in to change the bearing but I've never tried it so I don't really know.

The Wiz

Pull the engine and leave the trans. I find this easier than pulling both together, especially if the trans doesn't really need to come out for service.

Wayne
Wayne Pearson

This thread was discussed between 11/04/2007 and 16/04/2007

MG MGB Technical index

This thread is from the archive. The Live MG MGB Technical BBS is active now.