At 07:07 PM 8/22/2000 -0400, Gordie Bird wrote:
>Yep, rubber seals on have simply disintegrated, both upper and lower.
Question is can I drive it the rest of season (couple thousand miles) just
keeping it greased, or must I park it now and go to work? Actually, it's
probably been this way most of summer. What might occur if I continue to
drive it?
The idea is to keep some grease inside, and the dirt outside. If you could
give it a shot of grease periodically, and the grease will actually come
out at all of the desided points at the same time, then this will flush out
the crud, keep it full of grease, and thereby also keep out the dirt, in
which case you could continue to drive it indefinitely with no seals at
all. Now back to that first "if".
On the MGA upper and lower swivel links there is just one grease fitting
per link. When you inject grease it would be nice if it actually came out
of both ends of the horizontal bushing and at the vertical pin seal point
as well. In reality, most of the time this isn't going to happen. The
slightest change of resistance in any one direction will cause the grease
so find another path of lesser resistance, so it seldom comes out of all
three points together.
You can increase your odds of achieving this unlikely event by first
placing a floor jack under the suspension arm, directly under the coil
spring, and lifting the wheel off the floor. This unloads all of the
suspension joints except the inner lower a-arm pivot points. Then when you
inject the grease there's no (or very little) mechanical load on the
joints, so it's more likely for the grease to find an easy flow route in
all directions at once. Subjectively I believe this will increase your
odds of success from around 5% to about 25% for any one joint, but your
odds of success on four consecutive locations will still be in the single
digits.
Because of this funny design trait, is is very likely that one or more of
the horizontal bushings or the vertical threaded link joints will be
starved for grease and will wear out sooner than you expect, even if you do
exercise a firm schedule of greasing it regularly. Sooner or later, given
enough driving, every MGA will eventually be needing to have one or more of
the horizontal bushings renewed. When it's time to do that, check here:
http://www.ntsource.com/~barneymg/mgtech/suspensn/susp1.htm
Barney Gaylord
1958 MGA with an attitude
http://www.ntsource.com/~barneymg
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