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Bill Pressler
01-05-2007, 06:12 AM
I just drove my Lark 130 miles home yesterday from the shop that put Delrin bushings up front and converted the car to silicone brake fluid. It's a shop that has experience in Studebakers among other makes.

In '89 I had a former Stude dealer shop rebuild the front-end (king pins, center pivot, control arm bushings, etc.). The car has been making squishing and squeaking noises at low speeds and when climbing in and out of the car for a few years, hence I decided to have Delrin bushings put in this time.

About twenty miles into interstate driving yesterday, the car began to vibrate. I let off the gas a bit and the vibration became more severe. The wheel was vibrating quite a bit. I hate to think about it, but this is pretty much what it felt like in '89 when it needed the whole front end rebuilt (although not quite as bad). After two or three thirty-second examples of this vibration, it quit. The remainder of the sixty or more miles home, mostly on interstate but also with some stop-and-go, it was as smooth as silk.

Any ideas?

Would putting in Delrin bushings lay bare worn-out f/e components, that didn't vibrate before?

Thanks, as always.

Bill Pressler
'63 Lark Daytona Skytop R1

Blue 15G
01-05-2007, 07:16 AM
My first thought was that it sounds like some lug nuts are loose on your wheels for some reason. But.... if that were the case, I don't think the problem would go away by itself as you said. Wouldn't hurt to check them anyway before looking at the more difficult stuff.

CHAMP
01-05-2007, 08:41 AM
I would want to jack the car up, pull the front wheels and check everything over to make sure nothing is loose. You might also want to grease the car also. If it quit like you say it could have been the bushings just settling in. If you are not familar with suspenion work you might want to get it back to the shop that worked on it.

GARY H 2DR.SEDAN 48 STUDEBAKER CHAMPION NORTHEAST MD.

64V-K7
01-05-2007, 09:05 AM
With Delrin bushings replacing the ones that used to absorb road shock, they will transmit the vibration/shock/problem, through, to the next level, that will. Hopefully, they used grade 8 or 10 hardware, with toplock nuts, to remount your control arms and increased the torque level, used to fasten them. Usually when you replace the bushings with normal hardware , you have to retighten the nuts after a couple hundred miles. If there's anything loose in your system, Delrin will invariably cause it to be made 'looser'.

Bill Pressler
01-05-2007, 09:32 AM
Thanks for the advice. You are all a great group, especially to a mechanical dummy like me!

The shop is a long way from my home, and I don't know suspensions, but I'll keep my eye on it. I made the shop aware of it with an email and told them it went away the last half of the trip. They responded for me to keep them informed about it.

Sorta unfortunately, I drove it directly to a friend's place seven miles from here. I thought I wouldn't get it back out of his garage space 'til springtime. Of course with the mild winter we have had so far, I might get it out again on a dry day and take it out on the highway again. I had pretty significant body work done on it about twelve years ago, so I hesitate taking it out when there's any salt on the roads whatsoever!

Bill Pressler

chocolate turkey
01-06-2007, 09:26 AM
Before driving it again, I would take that advise to jack it up, wiggle the wheels back and forth, up and down as well and verify that there isn't a loose wheel or wheel bearing. There's no way a new set of Delrin bushings would be causing that kind of vibration, but the assembly of the components to get there would.

Brian K. Curtis

bradnree
01-06-2007, 12:32 PM
Every time I've had steering wheel shimmy/vibration it was a poorly balanced tire/or bad tire........Brad

PackardV8
01-06-2007, 08:19 PM
That the vibration comes and goes is quite puzzling. Usually, front suspension and tire problems come to stay. However,


quote:Every time I've had steering wheel shimmy/vibration it was a poorly balanced tire/or bad tire........Brad

Possibly compounded by weak shocks and/or lack of caster in the suspension alignment.

Are you running radial or bias tires? What air pressure?

thnx, jv.

PackardV8

bradnree
01-06-2007, 09:32 PM
My problems came and went depending on the highway speed....Brad

GTtim
01-06-2007, 09:54 PM
Just a thought here, but perhaps it was due to something sticking in the front brake that caused the brake to be slightly applied. That in turn caused the brake to overheat at highway speed which made the drum distort which caused the vibration which caused whatever was sticking to let loose and return to normal? Or maybe you applied the brakes and that returned it to normal. I'd check the brakes and look at the shoes to see if they are more worn than usual. Did you smell anything unusual while it was happening?

Tim K.
'64 R2 GT Hawk

Bill Pressler
01-10-2007, 06:59 AM
Sorry so long in responding, I'm in Baltimore now with work.

I run between 30 and 35 lbs. in each tire, and they are radials (195-75's).

Tim, at one point I did in fact think I smelled a "hot" smell. Also, my buddy who was following behind me, told me that at about that point in the trip he smelled an "asbestos-like" smell (whatever that is, now that there isn't asbestos in brakes anymore, right?).

In the meantime, I plan to make sure lug nuts are tight and jack it up and look for possible wheel "wobbles" indicating a bad bearing.

Thanks everybody,
Bill Pressler
'63 Lark Daytona Skytop R1

John Kirchhoff
01-10-2007, 10:44 AM
I just now noticed the post I sent a while back never got posted, probably my stupid dial up, sometimes it's very recalcitrant.

It may be easier to first figure out what isn't the problem. At 60 mph, the wheels are going to be turning around 700 rpm, but the driveshaft will be turning 3-4 times that speed depending upon the axle ratio. A driveshaft related problem is going to have a high frequency (around 40 times a second @60 mph), low amplitude (usually) vibration. A wheel balance or tire carcass problem will have a lower frequency shake (10-12 times a second @60 mph). If the shake regularly comes and goes or changes in amplitude every few seconds, that's caused by the harmonic resonance of two wheels being out of balance and turning at slightly different speeds. However, an unbalanced wheel shake isn't going to disappear like yours did. The only time I've had a vibration go away while driving was after driving through mud and a big chunk inside the wheel finally flew out, after the tires warmed up on a heavily loaded truck that set overnight in cold weather and after I pried a fist sized rock out from between duals.

If you think it's a tire, you might first jack up each wheel and rotate it. I've had pretty new tires have a belt slip or actually be offset on the wheel when mounted. I've had two of those, one sidewall will be much straighter with less curve than the other one, the tread is offset from center and is a manufacturing defect. They may be ok on the rear for a while, but can be a real devil when on the front. Check for any lumps, bumps or distorted tread. To isolate the bad one, you can replace one wheel at a time with a known good tire (spare?) until the shake disappears. A bad tire is usually most noticable on the front where the vibration will usually be felt through the steering wheel. It may take a few swaps, but if it's a tire problem, you'll get it.

If the shake, rattle or roll occurs at a frequency of a couple of times a second or starts or stops after hitting a bump, you might look for loose tie rod ends or other suspension bearings or bushings. Since your steering wheel shake came for a couple of periods and then quit, you might check the wheel bearings, especially the front. I had a periodic steering wheel shimmy that was caused by loose front wheel bearings. Had another steering wheel shimmy just last year that was caused by a radial tire with a very slight twist in the carcass. I wasn't able to detect the twist until I dismounted the tire after swapping wheels to isolate it. Good luck!

studeclunker
01-10-2007, 12:37 PM
You know, this sounds like the problem that the New Zelander was having too.

Pete, I think his name is...
http://studebakerdriversclub.com/sdc_forum/topic.asp?TOPIC_ID=7858

http://i16.photobucket.com/albums/b18/Studeclunker/studebaby/54wagonblue-2.jpg
Lotsa Larks!
K.I.S.S. Keep It Simple Studebaker!
Ron Smith
Where the heck is Lewiston, CA?

mike gaines
01-10-2007, 01:57 PM
I had endless problems with my silverhawk front end , I found the other day that the top securing nut on the right side shock had worked loose , no lock nut ! Tightened it up , problem solved , might be worth checking , shop may have overlokked this when they did the suspension.

GTtim
01-10-2007, 08:18 PM
Bill, asbestos or no, hot brakes have a very distinctive smell. If you were catching a whiff of a distinctive something hot, I would take the drum off and give the brakes a good looking over. If the drums are a bit out of round, and maybe the shop set them too tight when they put them back together, highway speeds with these conditions can cause the brakes to overheat and with the out of round drums, vibration will be evident. Other mistakes can happen, like installing the self-adjusters backwards, wrong shoes on the front side, etc. Hope this helps.






quote:Originally posted by Bill Pressler

Sorry so long in responding, I'm in Baltimore now with work.

I run between 30 and 35 lbs. in each tire, and they are radials (195-75's).

Tim, at one point I did in fact think I smelled a "hot" smell. Also, my buddy who was following behind me, told me that at about that point in the trip he smelled an "asbestos-like" smell (whatever that is, now that there isn't asbestos in brakes anymore, right?).

In the meantime, I plan to make sure lug nuts are tight and jack it up and look for possible wheel "wobbles" indicating a bad bearing.

Thanks everybody,
Bill Pressler
'63 Lark Daytona Skytop R1


Tim K.
'64 R2 GT Hawk