I am grateful for all the prompt replies to my question
regarding the apparent high running temperature of the Moss
gearbox in my 1951 Morgan +4. So many have been received in
just one day I have decided to construct just one reply, to
all in chronological sequence related to their receipt, with
appropriate comments and relayed statements that may assist
in making the subject clear.
I trust this is a suitable response to all those who
provided me with advice and I hope it "tells a useful
story".
Neil Montilla stated he switched to synthetic gear oil in
his ford powered 62 4/4 with quiet and cool results. Sounds
like good advice but I am unsure if it is suitable to my
early gearbox which has near "straight cut" gears and old
fashioned synchros which do require some friction for their
operation. Neil, I will investigate if a synthetic is
available to suit my gearbox and will advise all if
available and capable of being used.
Batesmcl advised his 67 +4 Moss box got hot and suggested I
take the top off & have a peek, and asked if it was making
any unusual noises. He assumes I am using the correct oil
and suggests synthetic, HD and asks further if non-detergent
is required. He continues with the statement that the gear
lever, at its base, got too hot to hold. Thanks
"Batesmcl". I have taken the top off and investigated. In
fact last time I investigated I removed the gear box to look
for problems, dismantled, replaced the front bearings,
which were a little rough when rotating after cleaning, and
everything else looked in good condition. The gear box
assembled OK and all shafts and bearings rotated cleanly,
quietly and with apparent low friction (turning by hand).
The answer on synthetic is above (to Neil). I do not think
HD (is that "heavy duty" or "hypoid"?) is suitable as my
Owners Manual definitely states SAE30 oil, and the oil
manufacturer here in Australia (Penrite - a company that
specialises in making oils for vintage & classic vehicles)
has advised I should use SAE30 gear oil. The Moss box does
not use detergent oil, but the Owners Manual implies this is
OK to use (ie. Ordinary 30 weight engine oil). But the
manual is over 40 years old and I suspect "detergent oils"
in those days probably did not have the sophisticated
detergent additives of modern oils. Thanks for the "hot
gear lever" comment. Mine also gets too hot to handle!
Will Zehring asks if the Moss box is directly mated to the
engine. The answer for my car is No. An alloy housing
about 700mm long separates the gearbox from the rear of the
Vanguard engine/clutch (placing the gearbox near the seat).
The heat generated from the gearbox is noticeable long
before heat transfer from the rear of the engine block.
Yes, the heat generated keeps the car quiet warm, even
through the transmission tunnel cover (no heater required!)
- but here in our sunny part of Australia this can be a
little uncomfortable if you are not an enthusiast.
Dave & Linda Freeman advised that vintage racers (probably
Jags) were running synthetic oil with good results. The
Moss box in my car is, I believe, the same as that installed
in Mark 5 Jaguars. Perhaps if a single weight 30 synthetic
is available this will be an option to consider. If I do
try I will let you know. Thanks & continue "the good life".
Obviously, driving a Mog helps produce the good life
feeling!
Ken in Sweden advised almost the same thing (heat) occurs in
his 1959 +4 gear box. Thanks Ken. If I find a solution you
will get to know. In the mean time, the replies and my
comments may make some interesting reading!
Tony (Daphne, AL, USA) states his Owners Manual (1971 +8,
Moss Box) requires 90 weight oil. I have been advised
against this for the 1951 +4 as it slows the synchros in the
old Moss boxes so much that it is difficult to change gears
without crunching. My Owners Manual clearly states in more
than one place to use 30 weight oil.
Scott Barrie agrees with Tony. He uses 90 weight hypoid
gear oil in his 1963 +4. Cheers & happy mogging to you
Scott.
Chuck Vandergraaf lists the types of oils that should be
used in the various 4 wheeler Morgans for the years up to
1963. This confirms my +4 should use 30 weight oil. Yes
Chuck, I have worked on the gearbox (a complete strip and
reassembly) and the +4 has a standard Vanguard engine. Yes,
the shafts spin quite freely with the gearbox installed and
I do not believe there is any misalignment of the
clutch/engine to gear box jack shaft. I have installed the
shaft on a lathe and checked run-out and all is quite
accurate. My only question that arose from my dismantling
and reassembly was: What end-play clearance (gap) should
their be between the jack shaft and the gear box inlet
shaft? My car seems to have about 1/8 inch (2.5 mm). Maybe
some one will have an answer or comment on this question?
Chuck, you did not mention if the base of the gear lever in
your 1952 +4 gets hot during travel. Can you please advise?
David Stillinger advises he uses 30 weight oil in his 1961
+4. David's comment on straight cut gears and synchro face
pressures not performing adequately with hypoid oils was
interesting. David goes on to say his Moss box does get
quite warm with the dip stick becoming too hot to handle.
Thanks David.
David & Pat Burket is interested in knowing what Neil
Montilla flushed his gear box with prior to using synthetic
oil and what grade/brand of synthetic used. Over to you
David. I am also interested in your answer to this.
David McCoy has always used 90 weight hypoid gear oil in his
1963 and 1966 +4's. Two Morgans! David, how do you get the
time to keep both on the road?
Thanks to everybody for your help. I suspect more replies
to my original question will arrive so I may be able to
continue the saga in the near future. I guess I shall
eventually be able to arrive at a summary and reasonable
balanced result.
In the mean time, for those who may not have seem my 1951
+4, have a look at:
http://www.onthenet.com.au/~tvhseng/morgan01.htm
(note: morgan "zero" one, not "oh" one)
Happy Morganeering and best regards to all. Thanks. Fred
Birkbeck.
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