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Jim_Gruber
09-20-2010, 05:55 AM
Question, Can a wishbone be rebushed more than once. One of the wishbones I replaced on Bugsy, my '68 Sprite came with a rear zerk already installed. My assumption is that this one was rebushed at least once. Having issues with front end sway, following road grooves, etc. All other front end parts have been replaced and renewed but since I am getting definite noise from LF, cluking, and shudder when I hit small bumps I know that at least the LF needs to be rebushed and while I am in there figure on rebushing both sides.

To keep off the road time to a minimum, anyone got a set of wishbone w kingpin assemblies they want to part with for a reasonable price. Looking for a set predrilled for a sway bar so they would need to come off of a later Spridget. Plan would be to clean up wishbones and send out to be rebushed while I still have Bugsy available to drive this Fall for the really fun Spridget Drive Time. Downtime can be minimized that way. Thanks.

mrsprite
09-20-2010, 10:41 PM
I don't see why not. Unless there is something physically wrong with the control arm (crack, dent, bent, chunks missing, etc.) you should be able to rebush it as many times as it needs it.

JPSmit
09-21-2010, 06:21 AM
Bushings are rubber and designed to wear, can't imagine a scenario where you couldn't do it again, except perhaps where someone let it go so long they distorted the metal.

In terms of the rebush - it is a real easy job - just go ahead an do it, the amount of labor involved in replacing the wishbone/ kingpin is exactly the same as just re-doing it. If your kingpin bushings are worn you will need them reamed but other than that, pull out, clean, add bushings, reinstall, drive. Afternoon job.

Trevor Jessie
09-21-2010, 07:13 AM
Jim, double check the vertical play of your stub axle. If you have too many shims under that trunnion you can have the issue you describe. But worm lower fulcrum bushings cause the same too.

ichthos
09-21-2010, 08:36 AM
I am not sure what is reasonable, but I bought two core a-arms from Apple Hydraulics for $40. I had my original a-arms rebuilt, (The PO drove my Bug until the bushings were so bad where the king pin attaches that it was metal to metal contact!)but then decided later that I wanted an antisway bar. I didn't have the support gussets, so I transfered the gussets from the ones Apple sold me (they had some damage where the bushings went in but the gussets were perfect), drilled the holes, and then welded them in place. Kind of a pain and time consuming. They said they would supply the gussets, drill the holes, and weld them for $75 a piece.
Kevin

Guest
09-21-2010, 09:22 AM
I'm with JP. Unless you need kingpin bushings this is an afternoon job. FWIW, Moss has better quality bushings. I'm having to replace my VB bushings after less than 10K.

Jim_Gruber
09-21-2010, 06:10 PM
Guys my terminology is wrong. I'm talking about replacing the fulcrum pins. The PS Fulcrum pin has been replaced and reamed at least once as it has a rear grease fitting. Can it be replaced and rereamed? I believe the wear item is the bronze fulcrum pin not the wishbone or the kingpin.

Frank,
Only one washer on there as I recall but that was 8-9 years ago when I swapped a complete spare front end from a racer's spare parts and pieces. The used spares were far, far better than the parts that were on Bugsy. All other front end parts were renewed, bushings, ball joints, tie rod ends, rack pinion gear, etc. New shocks as well from Peter C. then. Now < 10k miles in last 9 years and always well greased but car feels scary on highway on roads with traffic grooves on them. Lots of steering action to keep the car straight needed. Now some parts and pieces may need to be renewed but at this point my suspect piece is fulcrum pins at least on the DS.

Is there a way to tell if kingpin itself has worn beyond where a new fulcrum pin will help?

Now ideally I'd like to find a set of wishbones and kingpin I can send out to get reamed and new fulcrum pins done while I still keep Bugsy on the road this fall. Trying to get a start on winter projects with thoughts of returning to Cheeseland next June.

jlaird
09-22-2010, 08:35 AM
Jim STOP. Please check your tow in/out 0 to an 1/8 inch either way. May just be your wandering prob on groves. Think it is called bump steer.

Trevor Jessie
09-22-2010, 09:07 AM
Bump steer is caused by the pivot point of the TRE (and length) being different than the control arms. Change in ride height may introduce more bumpsteer, but it has little to do with the toe-in. However, if his suspension is worn then setting the toe-in will be difficult as it will vary depending on where the suspension "rests" while he is adjusting it.

Roger
09-22-2010, 09:44 AM
Tramlining it's called, the tendency to want to follow grooves and such like can occur even on new cars.
Tyre width and softness can have a lot to do with it - even from new my Elise has a slight tendency to tramline.
Have a look at this Tirerack article. (https://www.tirerack.com/tires/tiretech/techpage.jsp?techid=47&)

jlaird
09-22-2010, 09:49 AM
Here is a direct quote from that article which I thought was quite good, sorry about the incorrect term. Sigh. I don't know it all.

Tramlining

Alignment settings can be key as well. The "camber" and "toe" settings both play a role in vehicle stability and the propensity for tramlining. Extreme positive or negative camber settings will make a vehicle more sensitive, especially when only one wheel encounters a longitudinal rut and/or groove at a time. Even if all the tires are "aimed" straight ahead when the vehicle is in motion, a tire that is "cambered" wants to turn. This is the result of the "camber thrust" generated by a leaning tire (it is also part of the explanation of how motorcycles turn). A vehicle suspension using lots of negative camber for competition or the track will experience more tramlining on the street.

<span style="color: #FF0000">Additionally, the drivers who use additional toe-out settings to encourage their vehicle to turn into corners better also encourage tramlining because the extra toe-out will reduce vehicle stability in a straight line.</span>

<span style="font-style: italic"> </span> <span style="color: #33CCFF">So check what you got </span>

In the case of the competition driver who uses non-factory alignment settings, the amount of tramlining that is acceptable has to be left up to the driver. For only street-driven cars, getting them aligned with negative camber and toe settings within the factory's specifications is an important first step.

Jim_Gruber
09-22-2010, 08:22 PM
Jack,

Toe is set at 1/8". I do have a lowering kit on the car but I don't think that is the issue. I do fail the grab the tire at 6 and 12 o'clock test especially on the DS of the car. Hence my suspicion that fulcrum pin is worn and it's time to be rebuilt. When I hit a sewer lid there is a definite clunk from the DS and I can feel it in the wheel. It does this on PS as well but maybe 30% of the amount of clunk that comes from the DS. Again everything I read tells me it's a worn fulcrum pin.

While I'm in there my plan is to renew both sides even though the PS has been redone at least once, that rear grease fitting didn't come on there from the factory. PS may not need it but then I know both sides are theoretically the same.

Can anyone tell me what year Wishbones came standard with holes predrilled for Sway Bars and with the added gussets welded in place? The wishbones on Bugsy now are much, much heavier duty than the set I pulled off of a '68 Spridget.

Turns out one of the wishbones I had hoped to use has a major crack along fulcrum pin area. I now know why this Spridget stopped being driven, wheels wouldn't stay straight.

Guest
09-22-2010, 10:53 PM
FWIW, I had a crack and a welder. Now I just have a welder.

jlaird
09-23-2010, 09:39 AM
Jim, I think you covered your problem nicely. The front end needs rebuilding.