After much procrastination, I finally began rebuilding Sarah's (my
TR-4A), front suspension. After a weekend's work, I pretty much have
everything disassembled, and have assessed the damage.
Damage? Yes, damage. Sarah was in an accident at least 10 years ago,
probably longer, that did some damage to the right front suspension. The
lower A-arm attachment brackets are visibly bent, and the wheel sits too
far back in the wheelwell. I've been procrastinating because I didn't
know what I would find, and was afraid of it.
It looks like several hundred $$ worth of suspension parts are needed.
The lower A-arm brackets on the damaged side are as much as 1/2 inch out
of spec. I need at least one trunnion. One vertical link is bent at the
ball joint socket (that is, the axis of the ball joint thread and the
threaded portion that fits the trunnion aren't along the same line).
And one of the bolts that holds the lower A-arm to the frame bracket
onthe damaged side was 1/8" too small! Now wonder there was shake at
speed. (I'm glad I didn't try to autocross her before doing this work.)
And, of course, I have several questions to ask:
Why are trunnions made of brass? The 4A (and 250 and 6) trunnion
supports the bottom of the vertical link. It is the apex of the lower
A-arm, and connects to the two A-arm brackets with a long steel bolt
that runs through all three pieces. In the two brackets (they're cast
iron), there's a metal sleeve and nylon bushings. But the bolt runs
directly in the brass of the trunnion. I don't understand why - it's
guaranteed to wear, and it's a difficult part to replace. The only
thing I can think of is lubrication -- the vertical link is drilled and
the passage from the nipple ends in the bolt passage.
(My trunnions actually seem to be in good shape -- there's a touch of
play, but I'd guess it's within .001". I have to replace one, though --
as mjb predicted, the steering stop bolt sheared off and I can't extract
it. Should make a nice paperweight :-)
How do you get out REALLY recalcitrant bolts? I had real difficulties
with the bolts that hold together the vertical link, caliper mounting
plate and tie rod lever, on each side. The very long bolts were rusted
to the parts they pass through. I got one out by pounding on it, two out
by putting it in a hydraulic press, one is still sitting after being
pounded, pressed, ground and chiseled (it'll come out with a chisel, but
I ran out of patience), and one will simply not budge. This last one has
been subjected to five tons of pressure -- enough to press out the
threads on the nut that I had in place to protect the end. I can't get
it quite vertical in the press, so I don't want to use more pressure.
Solvents? Drill it out? Other ideas?
The upper A-arm brackets on both sides are bent, in a funny way. Not in
a way that distorts the suspension geometry -- rather, in a way that
makes it difficult to get at the ball joint bolts. The upper brackets
are basically C-shaped in section, stamped from steel. (The lower
brackets are cast iron.) On both sides, more on the left than right, the
top part of the C is chewed up, pressed in (making the C more like an
O). I'm curious: what could have caused this? Too much suspension
travel? There's nothing to hit! Also, any suggestions for repairing
this?
Tomorrow, I'll order parts and see just how much is backordered. Sigh.
chris
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