What are your preferred solutions to the problem of extending the life of the kingpin bushings? M. Boulet. 15/09/99
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Wear in the kingpin bushings is accelerated by road grit getting into the lower bushing through the gaps in the lower or "rebound" spring.
Assuming you wish to drive your car in inclement weather, anything you can do to prevent grit from entering through this gap will improve the life of the pins and bushes. A flexible leather or plastic "gaiter" or cover over the spring would help. Cleaning the assembly off at a "quarter wash" would help.
Greg Solow offers hard chromed kingpins which can considerably extend bushing life as well.
Hope this has been of help to you.
JOHN H. SHEALLY II
Any answer that I give on a question is what I do and has proven to work for me on my Morgans. The key to long living Kingpins is to first have them fitted properly. Have them machined so that the bushings fit very snug on the kingpins. This is done so that the bushing has a very close fit but able to move freely (most people fit them too loose which really adds to a short life.) After the fit, I then take a hacksaw blade and apply a good thick bearing lube to the blade and fill the space between the upper and lower bushings in the stub axle. Apply a nice coat to the kingpins and insert them into the bushings . At that point with the nice close fit they will last a good 90 thousand miles with no problems. I do not use the one shot at all. Use it if you wish but all it does is make a mess on the under wing of the Morgan. If you do use the one shot only do it on start up. Remember the fit and pre-lube is the secret.
Best to you/Sincerely/John
H. Sheally II
When my original bushings were worn out at 14,000 miles from new on my '64 Morgan +4, I decided that the front suspension wearing out in that length of time was absurd, and something needed to be done to prevent the same thing happening a second time. I consulted a metallurgist who assured me that the bushing material used was excellent and that the problems causing the premature wear were that the kingpins were not hard enough and that their fit was not precise enough.
We came up with the
solution of hard chroming and centerless grinding the kingpins and fitting
them to the bushings in a more precise manner. The second set of bushings
lasted from 14,000 miles until 95,000 miles, and at that point, the kingpins
were not worn out, only the bushings showed wear. We have since improved
the procedure to make it even more durable. We recommend that
the front suspension be greased at the regular zerk fitting on the spindle
every 1500 miles with normal chassis grease and that the built-in oiler (the
one-shot oiler) not be used as a normal matter of course. We have not
found it necessary to fit any form of "gaiter" or dirt excluder to the front
suspension. Of course fitting such a device certainly can't hurt as
long as the chromed kingpins and new bushings are fitted with the correct
Regards, Greg Solow
Our experience with kingpins & bushings has not been as severe as Greg's nor has our solutions been as extensive. Our first set on the 1959 Drophead we bought new lasted about 40,000 miles (2 years - we drove our MORGANs more then, it was the only car we had for a while.) Our first indication that something was amiss was a severe case of St Mog's dance coming home from the Santa Barbara road races. Perhaps we just let them go farther than Greg did.
We have not used anything other than the factory (or Melvyn Rutter) supplied parts but are careful to ream them accurately at installation. I would think that you still have to ream the bushings after installation when using chromed kingpins. Greg might want to comment more on that. The idea of harder kingpins has been around for a long time and seems the proper idea but we have just never used them (inertia). We have also always used the factory "one-shot" oiling system. I think oil provides better lubrication than grease. I think that in the original design, the purpose of the grease (at the bottom bush) was to keep the oil in.
The one "innovation" that we have been using since 1959 is to install an "O" ring to keep the oil in and the dirt out. This is done by pressing the new lower bushing in about 3/16 inch deeper than normal. After reaming, cut a 1/8 inch long piece from the old bushing, insert an "O" ring into the Spindle and then drive in the old piece to secure it. One must be careful to clear the oil passage at the zerk fitting as driving in the new bushing deeper may obscure it. The procedure is detailed in the front suspension article that I wrote for John Blair's web site. We have also gotten 100,000 mile kingpin life this way. I often speculated that, if one used chromed kingpins AND the "O" ring seal, would the average person EVER have to replace kingpins again.
We have never used
gaiters.Too much work.
GoMoG Webmaster: The world has long moved on from the time that
these comments were made (along the lines suggested by Greg Solow and
eMog). Please consult the relevant section of the GoMoG Manual