392
Spares
are a concern when servicing a high mileage V8 back axle
Gordon Hesketh-Jones (Harvest Gold 1904) from Cornwall has clocked
up over 400,000 miles in his MGBGTV8 and relates his experiences
with spares for back axle servicing. (Nov
08)
Parts diagram: page 22 MGBGTV8 Parts
Supplement MGL001B (Moss)
About
80,000 miles ago I started to hear a clicking noise from the
differential every time I took my foot on or off the accelerator
although the differential on Harvest Gold 1904 was still delightfully
howl-free, unlike some of the new Italian-made ones I have heard.
Obviously I checked and re-checked the universal joints on the
propshaft but they were still both quite new and in good condition,
so I drove the car along to Cornwall & Devon Transmissions
at St Austell. After a test drive and an examination they felt
that the wear was in the crown-wheel and pinion - which obviously
did not fill me with joy. So a few weeks later I stripped the
back axle from the car and took it to them. I was then delighted
when they phoned to say that the CWP was in excellent condition
but just needed re-shimming and that also all seals and bearings
needed routine replacement.
More recently the ominous clicking started again but with the
differential now having covered well over 400,000 miles I felt
I really could not complain and made another trip to St
Austell. After the road test their engineers were a bit puzzled
but examination on a hoist made it clear that this time the
clicking was coming from the front nose of the differential
casing. Once again the axle was stripped out, brake hubs removed
etc and off it went to St Austell, but this time the news was
not so good for both of the two pairs of planetary gears were
badly worn. Worse still was the fact that of the larger pair
(BTB428), MOSS had just one single gear in stock @ £103.70
plus VAT, whilst the
smaller pair (BTC9001) had the dreaded "NLA" |
Section
G: Rear Axle & Propshaft Assembly
Parts list:
page 23 MGBGTV8 Parts Supplement MGL001B (Moss)
(no longer available) marking on the MOSS computer. In addition
the collapsible spacer (BTB853) was also NLA. I phoned around
to Rimmers, Brown & Gammons, Clive Wheatley, MGB Hive etc
but without success and depression set in.
More
research on the MOSS catalogue made me realise that the MGBGTV8
differential is virtually identical to that of the standard
later-model MGB, apart from our 3.07:1 ratio crown-wheel and
pinion of course. Now, many years ago at a workshop clearance
sale I had bought a complete MGB axle; I knew that my planetary
gears had been OK at around 330,000 miles, and even though I
did not know the history of the standard MGB axle that had languished
under my work-bench for around 12-14 years, I doubted if it
had even covered 50% of 330,000 miles. So another drive to St
Austell, hoping madly that the gears in that back axle were
in good condition and could be used along with the rare collapsible
spacer that Tim Kelly had found for me. The result - success
and a minor bill for £322 which included £70 plus
VAT for numerous new bearings and seals and also the strip-down
then re-assembly with my spare axle. The rebuilt V8 back axle
is now totally silent again.
The
moral is clear - if you see an MGB tube-axle for sale at a reasonable
price - BUY IT! |
