I have a 79 B, looks like it had a motor swap at some point, maybe a 77 motor now. 4 speed side filed transmission. I was able to obtain a 72 O/D MGB, that sat under a tree for years. I got it running but could not drive it to check the O/D, I jacked up the rear wheels, put some used motor oil 20W-50 in it, ran it up to speed, up shift down shift as fast and slow as I could, no grinding. (it seems to me any sync problem would have shown up) I opened up the trans, cleaned it (may be #1 mistake)redid all the "O" rings, per Mr. Twist's video.
installed, with new 20W50 oil, O/D works great but 3rd to 2nd is bad, it needs to be under 20mph, no speed shifting, and shifting to 4th the gear shift needs to be pushed to the right to line up. I installed a new clutch disk, but used the old pressure plate and throw out bearing (carbon) which still had a lot of meat on it. The clutch slave throw is 3/8", and it seems to be working freely.
So here are my questions before I start taking it all apart again?
--Shouldn't a sync and shifting problem show up testing the trans. with the rear wheels free wheeling?
--Would lighter oil, or heavier oil, make a difference? (I doubt it but I thought I'd ask)
--Other then the four sync's anything else to specifically look for, (since my problem is always, "is this part worn or supposed to look like this"?)
--Is shifting to 4th and having to push the stick to the right for proper alignment, a sign that the shifting fork is worn out, or could it be some other part?
--Or maybe I should just dump used motor oil in it again !
Thank you for any advise on what to look for when I get in there.
installed, with new 20W50 oil, O/D works great but 3rd to 2nd is bad, it needs to be under 20mph, no speed shifting, and shifting to 4th the gear shift needs to be pushed to the right to line up. I installed a new clutch disk, but used the old pressure plate and throw out bearing (carbon) which still had a lot of meat on it. The clutch slave throw is 3/8", and it seems to be working freely.
So here are my questions before I start taking it all apart again?
--Shouldn't a sync and shifting problem show up testing the trans. with the rear wheels free wheeling?
--Would lighter oil, or heavier oil, make a difference? (I doubt it but I thought I'd ask)
--Other then the four sync's anything else to specifically look for, (since my problem is always, "is this part worn or supposed to look like this"?)
--Is shifting to 4th and having to push the stick to the right for proper alignment, a sign that the shifting fork is worn out, or could it be some other part?
--Or maybe I should just dump used motor oil in it again !
Thank you for any advise on what to look for when I get in there.