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Transmission Rebuild

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Transmission Rebuild
#1
  This topic is about my 1961 Morgan Plus 4 (+4)
61highline Tim Remesal
Santa Rosa, California, USA   USA
1961 Morgan Plus 4 (+4) "61Highline"
I just purchased a "Good" 4 speed all syncro TR3 transmission for my 61 +4 restoration . I'm tempted to dismantle it and check it out . Have any of you done that ,or are special
tools and gauges needed? I also have the original transmission . Mostly all the parts. Did all 4 syncro start in 62 ? Thanks , Tim

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racekarl Karl K
Medfield, MA, USA   USA
My '62 plus 4 has a non-synchronized first gear

BuyBritish Rob D
Ipswich, Suffolk, UK   GBR
we are about to rebuild our 1958 moss box

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61highline Tim Remesal
Santa Rosa, California, USA   USA
1961 Morgan Plus 4 (+4) "61Highline"
Rob: My bell housing got damaged in transport so I may be rebuilding my original . Have you done this before? Are there any good reference vids ?
Thanks , Tim

DuncanCharlton Avatar
DuncanCharlton Duncan Charlton
Elgin, Texas, USA   USA
1931 Morgan 3 Wheeler "Gwenda (Sold)"
1967 Morgan 4/4 "Toly's Car"
1967 Unknown Unknown
1970 Mini Countryman    & more
All Plus 4s used the Moss gearbox (as did the early Plus 8s), which had a non-synchro first gear. Jaguar used a Moss gearbox that is interchangeable (not counting the front, top and rear alloy covers) with the Morgan one up until perhaps the mid-1950s and later developed a similar gearbox with a synchro first gear for use in the E-type and sedans. The Morgan 4/4, on the other hand, got a full-synchro Ford gearbox with the introduction of the Series III I think (1960) but I don't have access to my library at the moment to confirm this.

Rebuilding the Moss gearbox is not difficult and no special tools are required other than a length of 1" wood dowel. I've done it three or four times. Parts are available through Jaguar restoration specialists and from Greg Solow at The Engine Room in Santa Cruz, California. Fred Sisson's "Morgan Bedside Reader" has a very thorough layman's description of the steps involved (you should be able to get a copy through David Crandall at mogdriver@gmail.com) and I can send you a scan of the relevant pages of the Jaguar manual which includes the clearances and such.

61highline Tim Remesal
Santa Rosa, California, USA   USA
1961 Morgan Plus 4 (+4) "61Highline"
Duncan: Thanks for the information . Now I'm inclined to take on the project . Definetly will keep the matching numbers transmission with my +4.

BuyBritish Rob D
Ipswich, Suffolk, UK   GBR
We are rebuilding the moss gearbox of our plus 4 1958 car gearbox covers all off about to remove the circlips and split rings

We have all new bearings and needle rollers but tolerances and the finer points of rebuilding the box correctly would be very useful

copies of the relevant set up sections on the moss box would be invaluable

the car in question is in the morganeer this month the barn find angel two tone blue/silver 4 seater car!

Please reply asap as have gearbox in front of me!

many many thanks

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DuncanCharlton Avatar
DuncanCharlton Duncan Charlton
Elgin, Texas, USA   USA
1931 Morgan 3 Wheeler "Gwenda (Sold)"
1967 Morgan 4/4 "Toly's Car"
1967 Unknown Unknown
1970 Mini Countryman    & more
Rob, I need your email address in order to send you the Jaguar manual, which includes the clearances. Send to duncan.charlton54@gmail.com

BuyBritish Rob D
Ipswich, Suffolk, UK   GBR

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BuyBritish Rob D
Ipswich, Suffolk, UK   GBR
I have had the lid off the gearbox and cleaned the 'chrome' swarf from the gear selector lever which had deterioated leaving chrome bits in the gear box

Gearbox was refiled with oil and ran a few miles then I could no longer select 1st gear it just wouldnt select it at all so what may be the cause?

I'm stripping the box down so it would be useful to 'see' what caused the 1st gear problem.

what order do I start removing the bearings/gears/circlips etc

Rob

DuncanCharlton Avatar
DuncanCharlton Duncan Charlton
Elgin, Texas, USA   USA
1931 Morgan 3 Wheeler "Gwenda (Sold)"
1967 Morgan 4/4 "Toly's Car"
1967 Unknown Unknown
1970 Mini Countryman    & more
I don't remember removing circlips. I sent you some general instructions in my last email but before you proceed, read the instructions in the Jaguar manual. The order of disassembly is important.

DuncanCharlton Avatar
DuncanCharlton Duncan Charlton
Elgin, Texas, USA   USA
1931 Morgan 3 Wheeler "Gwenda (Sold)"
1967 Morgan 4/4 "Toly's Car"
1967 Unknown Unknown
1970 Mini Countryman    & more
Rob, I looked at your photos and see that you went ahead and removed the rear cover. I did not bother with that in the instructions I sent you, because it comes off with the layshaft and reverse gear shaft if you follow my instructions. Getting the layshaft to seal properly in the cover is tricky enough but I think the O-ring for the reverse shaft may no longer be available. I would consider reusing the O-ring but smearing it thoroughly with a (non-silicone) sealant called The Right Stuff, which I've found to be a slight improvement over the black Permatex stuff (also not really a silicone type sealant although it comes in similar packaging).

You won't be able to get the upper (main) shaft and input shaft (on the same axis but not part of the same shaft -- it will make sense once you've gotten it apart) out unless you first lower the layshaft gear cluster (in the bottom of the gearbox) out of the way, and to do that you need to drive out the layshaft (the larger of the two shafts), preferably toward the rear. If you don't have a dowel you can always insert it later to keep the needle bearings from falling out during reinsertion of the layshaft.

Button Bill B
Seattle, Washington, USA   USA
I have a reconditioned "Bell Housing" +4 for sale.

Button

Walden MG-Morgan Avatar
Walden MG-Morgan Barrie Walden
Falmouth, MA, USA   USA
Rob,
I have the same Moss first gear problem as you (see my Moss Gearbox 1956 +4 at the Forum). I hope you will be able to find your problem and let me know. First gear problems usually occur with the gear installed and can’t be released. The opposite seems to be the problem for us. It would seem to be a problem with the mainshaft and the first/second synchro sleeve with the ball and plunger group, but second gear will probably not work either (and my does).

Please let me know what you discover.
Barrie

BuyBritish Rob D
Ipswich, Suffolk, UK   GBR
Well no damage or bad parts found bearings and springs in the sychro look ok bit stiff to select, did have chrome bits in the synchro sleeve but appear not to cause problems.
Im replacing all bearings and cleaning up swarf!

Ive taken lots photos, Duncan invaluable source of info.

There is a sprung loaded plunger/dowl on the mainshaft that has to be retracted to get to the roller bearings, but now I have to consider how I reassemble as the plunger must be retracted but how to hold it down while reinstlling gear with needle rollers is a challenge! Duncan?

my gearbox photos more uploaded soon

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