Marblehead MG - Episode 42: Clutch Clearance (1979 MG Midget 1500)

[@dangerman7231]

Very interesting. I have the same issue and have bleed the clutch many times. Looks like a need a 1/4” bushing too

[@GeekInAwe]

Thanks for this video! I am working on a 79 as well. I am currently replacing the clutch slave cylinder. I needed a sanity check that you confirmed. It seems odd that there is a gap under the slave clutch housing where it mates to the transmission. From your video, it looks like you have a similar gap. Seems like an odd design to leave that gap … Dirt. Water. Etc. Then again, I am quickly learning that these cars have an abundance of quirks.

[@marbleheadmg]

I've learned that sometimes these design "features" are to aid the manufacturing and assembly process, versus operation and maintenance.

[@skwdenyer]

Isn't the ultimate source of the problem play in the release pin / bush / tolerance ring? If those have wear, the spacer will be needed. But its also not possible to do that without removing the engine and gearbox - so maybe queue that up for next time those get removed?

[@marbleheadmg]

Yes, most likely that's the core issue, although the pin doesn't seem to have any play at the mount-point and overall clutch component set seems to be in reasonably good shape -- it is clearly an aftermarket replacement. Maybe that's the actual issue -- an aftermarket kit that isn't quite to exact specifications for the 1979 1500.

[@dangerman7231]

How would you verify those parts (pin, bush, tolerance ring) and how would you repair without removing engine/transmission?

[@marbleheadmg]

@@dangerman7231 it’s probably a trial and error approach. You could maybe build up material like aluminum foil in the slave cylinder cup until you determine the proper thickness that enables full clutch clearance. Then you could devise a more permanent component. That’s probably a fairly tedious job though. I don’t think you can actually repair/replace any of those particular parts without removing the engine. You could probably keep the transmission in place, however.

[@dangerman7231]

@ i added a copper 1” tube to the rod and it seemed to help about 75%

[@danielwoodard680]

Is the clunking sound occurring only in reverse? Otherwise, the drive sounded normal.

[@marbleheadmg]

The clunking is only in reverse yes -- it's due to a chewed-up reverse idler gear. We'll be replacing that over the winter.

[@dangerman7231]

Does anyone have exact measurements for this little extension. It is exactly what I need. After new Master, clutchline, and slave, I have the same issue. The clutch just won’t disengage fully unless I double clutch. I just need that 1/8” inch more.

[@beatnikgarage2153]

I am working on one currently (1971 midget) and the same issue is on this car. I replaced and bled multiple times, the master and slave cylinder, as well as replaced the rubber hose. The rod itself was quite worn so after I experienced the same results you all are, I decided bleeding it wasn’t the issue and realized the rod had been worn pretty badly. I would have estimated that the Clevis pin hole was oblong and about an 1/8” of slop was there, as well as an estimated 1/8 worn off the end of the rod that goes into the slave cyl. I actually welded a 1/4” of material back on the end and the pedal felt drastically better. My concern with making it too long is premature wear on the graphite bearing that is in the clutch fork. So you don’t want too add too much length. Before I added material, the total length of the rod was 2-15/16”, after repair, it measured 3-1/4”. I assume that the original length would have been about 3-1/8” total.

[@dangerman7231]

@ i ended up adding almost 3/4” to my clutch rod going into slave. Even with that, I get a bit of grinding shifting into reverse if I don’t shift into third first. I have no wear on pedal linkage. I must have a lot of wear in the internal parts of the tranny. Not sure but I can drive it.