Nels,
I would suspect that the squeek you are listening to is comming from
your generator and is a result of an excessively tight fan belt (and
probably one purchased from Moss Motors). The fan belt on the T series
cars need to be run extremely loose. You should be able to push on the
belt between the generator and the water pump (rather than on the
longest leg) and see almost 1 inch of slack. This is quite tight enough
for the T series because it is not driving an alternator that requires
a lot of torque to turn when it is producing current and the fact that
the fan belt is a large cross section truck and bus belt, which brings
up the other point, belts purchased from Moss Motors. Years ago Moss
got a large supply of solid backed belts that were barely long enough to
get on the T series engines. Even running these belts extremely loose,
put enough force ont he generator pully to cause excessive wear on the
rer bushing. After the bushing wears far enough, the armature starts to
rub against the field poles and produces that elusive squeak you ar
hearing. It will also destroy the armature (thus the generator) if not
corrected. I am pasting an article that another member and I wrote for
the newsletter of our local Register recently on this subject. The
article gives the part number for two different fan belts that should be
used on the T series engines (Nels, you will also need to get your
generator overhauled by a compentent auto electric shop).
Cheers (and keep your belts loose),
Dave
KEEP YOUR BELTS LOOSE
(DON'T BE SO UPTIGHT - LOOSEN UP)
by Dave DuBois AND Stuart Locke
All of you who have been around me for any length of time have heard me
preach about keeping the fan belt on the T series cars loose. A tight
belt will do really bad things to the generator (kind of like what over
tight underwear does to a person, but that is a subject for other
publications), like causing excessive wear on the rear generator bushing
and in severe cases, actually wearing through the bushing and into the
housing. It also causes sloppy water pump bearings and water leaks
according to Stuart Locke, who has rebuilt numerous generators and water
pumps for people that keep their belts too tight. The same thing is
true for the MGA and the early MGBs that use generators rather than
alternators. I have always followed my own advice and kept the fan belt
in our TD EXTREMELY loose. So you can imagine my surprise a couple of
months ago when I traced the source of squeaking in the engine
compartment to be the generator armature rubbing on the field poles
because the rear bushing was worn excessively. I pulled the generator
and did a quick overhaul, cleaning it up, replacing the rear bushing and
brushes and repainting it. Then I started puzzling out why the rear
bushing wore so quickly (if you consider 15 years to be quick).
Interestingly, at the same time I was working on an article, Stuart
Locke was doing the same thing some 600 miles south in Sunnyvale. His
article arrived about two days after I had given mine to Liz for the
Bonnet, so after consulting with Stuart, I am combining the two articles
Since the fan belt that was originally on the car when I bought it in
1974 was a bit over sized, I had replaced it when I restored the car in
the early 80s. At that time the belts from Moss were a solid and very
stiff belt, but I didn't give that much thought at the time. In
revisiting the situation after rebuilding the generator, I took a more
critical look at the belt I had been using and dug around until I
uncovered the original belt (the one that was too long). What I found
was that the original belt was a Gates Green Stripe belt that was
segmented on the inside edge and was, therefore, a very flexible belt.
When installed, it could be run very loose and as a result, put very
little sideways pressure on the generator pulley, which results in very
little pressure being transmitted to the rear bushing through the
armature. I then embarked on a search for one of these really flexible
fan belts and through trial and error and a very helpful auto parts
store in Bremerton, who special ordered goodness knows how many
different sizes of belts for me from Seattle, found the proper size
Gates Green Stripe II belt. This belt is also segmented on the inside
surface. Although the segments are much wider than on the original
Green Stripe belts, it still results in a much more flexible belt than
what I bought from Moss. The part number on this belt is TR22392 and it
is a 11/16" X 39 3/4" (17mm X 1005mm) Truck and Bus series belt made by
Gates. In his article, Stuart tells us that the Goodyear 22394 belt is
22/32" X 39 1/2" (17mm X 1005mm) and that the Moss belt is not only very
stiff, but is also considerably shorter at 17mmX 925mm (about three
inches too short), which I found when I was special ordering all those
belts trying, to find the right one. Additionally, Stuart found in a
1949 book, Exploring Auto Mechanics by Harold T. Glen that the fan belts
on the TCs and TDs (and by extension, the TFs) should be adjusted to
have ONE INCH of slack between the generator and the water pump (not on
the longest leg as we are used to).
By the way, as I said earlier, the same problem exists on the MGAs and
early MGBs, but is not so pronounced since they use the later style
narrow fan belts which are much more flexible than the ones used on the
T series cars. The fan belt still needs to be run quite loose (one half
inch of slack between the generator and the water pump, rather than on
the longest leg) on the MGAs and MGBs to prevent premature wear on the
rear generator bushings.
My source for the belts over here in Kitsap County is Westbay Auto.
Those of you in Seattle, Tacoma and other areas will have to check
around for the Gates belts or Stuart tells us the Goodyear belts are
available from Skip Kelsey (Shadetree Motors Ltd) at 925-846-1309. So
now you have no excuse not to loosen up and get comfortable.
/// unsubscribe/change address requests to majordomo@autox.team.net or try
/// http://www.team.net/mailman/listinfo
/// Archives at http://www.team.net/archive/mg-t
|