Negative Camber/Urethane Bushings

All Models and Years
lalkie01
Posts: 67
Joined: Sat Nov 16, 2019 2:02 pm

Negative Camber/Urethane Bushings

Post by lalkie01 »

I have a 65 corsa and just finished rebuilding the rear suspension. When I let the car down it had excessive negative camber. I was unable to adjust it to get a neutral camber. Are urethane bushings to soft and flex to much allowing negative camber? I have tried everything I can think of but the problem persists. Has anyone had these problems with urethane bushings? What else could affect the camber? Any help would be appreciated. Thanks Larry
User avatar
terribleted
Posts: 4584
Joined: Sun Apr 18, 2010 2:36 pm
Location: Atlanta, GA
Contact:

Re: Negative Camber/Urethane Bushings

Post by terribleted »

Can usually use the adjuster cams that mount the outer end of the strut rods to adjust from a lot negative to a fair amount positive cambers. Something assembled wrong? Springs cut? The original rubber was fairly soft I doubt urethane bushings made properly for this application would be softer. Do they require a sleeve inside them and if so is it installed....grasping at straws here.
Corvair guy since 1982. I have personally restored at least 20 Vairs, many of them restored ground up.
Currently working full time repairing Corvairs and restoring old cars.
https://www.facebook.com/tedsautorestoration/

Located in Snellville, Georgia
lalkie01
Posts: 67
Joined: Sat Nov 16, 2019 2:02 pm

Re: Negative Camber/Urethane Bushings

Post by lalkie01 »

I have the camber bolts adjusted the maximum amount and still when I drop the car down it still shows negative camber. There are sleeves in the bushings. The old rubber ones were hard as a rock. The new urethane bushings seems squishy as compared to the old ones. Nothing seems assembled wrong. I don't think anything could be assembled wrong. I have check the pictures and everything looks ok. Larry
User avatar
terribleted
Posts: 4584
Joined: Sun Apr 18, 2010 2:36 pm
Location: Atlanta, GA
Contact:

Re: Negative Camber/Urethane Bushings

Post by terribleted »

I have seen strut rods upside down, adjusters not installed, no special washers to locate the mounting bolts in the center of the sleeves and adjust the sleeve diameter down to that of the bolts, etc.
Corvair guy since 1982. I have personally restored at least 20 Vairs, many of them restored ground up.
Currently working full time repairing Corvairs and restoring old cars.
https://www.facebook.com/tedsautorestoration/

Located in Snellville, Georgia
66vairguy
Posts: 4627
Joined: Tue Dec 21, 2010 3:44 pm

Re: Negative Camber/Urethane Bushings

Post by 66vairguy »

Did you roll the car one car length (at least) after "letting the car down". Moving the car lets the suspension neutralize and should always be done after a car is lowered on tothe tires to relieve stress on the bushing.
User avatar
terribleted
Posts: 4584
Joined: Sun Apr 18, 2010 2:36 pm
Location: Atlanta, GA
Contact:

Re: Negative Camber/Urethane Bushings

Post by terribleted »

66vairguy wrote: Fri May 22, 2020 3:31 pm Did you roll the car one car length (at least) after "letting the car down". Moving the car lets the suspension neutralize and should always be done after a car is lowered on tothe tires to relieve stress on the bushing.
Good thought!! Down jacking results in positive camber (tops of tire tipped out) normally until the car is moved.
Corvair guy since 1982. I have personally restored at least 20 Vairs, many of them restored ground up.
Currently working full time repairing Corvairs and restoring old cars.
https://www.facebook.com/tedsautorestoration/

Located in Snellville, Georgia
User avatar
flat6_musik
Posts: 2659
Joined: Sun Apr 04, 2010 10:03 am
Location: Hesperia, CA

Re: Negative Camber/Urethane Bushings

Post by flat6_musik »

I don't think I'd blame the urethane bushings. It was probably like this before you changed them out, right? I'm thinking cut or sagging springs too.... BTW, I always thought urethane bushings were usually associated with being TOO hard, compared to the stock rubber.
lalkie01
Posts: 67
Joined: Sat Nov 16, 2019 2:02 pm

Re: Negative Camber/Urethane Bushings

Post by lalkie01 »

I have driven the car it makes the negative camber worse than just letting it down. The bushings squish out around the frames. Rods not upside down. I removed one side and in the process of putting in some other bushings got one side about done. I am not sure where I got the grey squish bushings I have had the a while. I was only able to get one the special washers on one side of the bushing. Still working with it. Larry
66vairguy
Posts: 4627
Joined: Tue Dec 21, 2010 3:44 pm

Re: Negative Camber/Urethane Bushings

Post by 66vairguy »

lalkie01 wrote: Sat May 23, 2020 5:29 am I have driven the car it makes the negative camber worse than just letting it down. The bushings squish out around the frames. Rods not upside down. I removed one side and in the process of putting in some other bushings got one side about done. I am not sure where I got the grey squish bushings I have had the a while. I was only able to get one the special washers on one side of the bushing. Still working with it. Larry
Urethane "hardness" is measured with a durometer. While typically "harder" or stiffer than stock bushings for racing, they could also be softer. Since you're not sure where you got them, plus the fact they "squish" out of shape make me think they are the problem. Sometimes aftermarket parts are not well made. I know when the stock rubber bushing quit (usually inside due to gear oil leaking) you end up with a lot of negative camber.

Posting a picture of the "squished" bushing would help.
User avatar
terribleted
Posts: 4584
Joined: Sun Apr 18, 2010 2:36 pm
Location: Atlanta, GA
Contact:

Re: Negative Camber/Urethane Bushings

Post by terribleted »

Squishing out of the strut rods and brackets? That is not a good sign. If they are too soft they will allow the strut rods to be effectively too long and could cause negative camber. even badly compromised rubber bushings do not usually squish out of the strut rods much.
Corvair guy since 1982. I have personally restored at least 20 Vairs, many of them restored ground up.
Currently working full time repairing Corvairs and restoring old cars.
https://www.facebook.com/tedsautorestoration/

Located in Snellville, Georgia
User avatar
bbodie52
Corvair of the Month
Corvair of the Month
Posts: 11897
Joined: Mon Aug 06, 2012 12:33 pm
Location: Lake Chatuge Hayesville, NC
Contact:

Re: Negative Camber/Urethane Bushings

Post by bbodie52 »

I suggest that you browse through these Corvair Forum threads and the attached shop manual and assembly manual extracts and see if any of this information, material, and the illustrations and videos help in determining just what is wrong. If you could post some pictures of your own showing the questionable issues on your car we might be able visualize it better and figure out just where the problem is.

rear camber
:link: viewtopic.php?f=55&t=14183&p=98444&hili ... rut#p98444
Rear wheel camber
:link: viewtopic.php?f=55&t=13220&p=91265&hili ... rut#p91265

Image


:chevy: :wrench: :omgosh: :dontknow: :confused: :fingerscrossed:
Attachments
1965 Corvair Assembly Manual - REAR SUSPENSION.pdf
1965 Corvair Assembly Manual - REAR SUSPENSION
(4.32 MiB) Downloaded 27 times
1965 Corvair Chassis Shop Manual - SECTION 4 - REAR SUSPENSION.pdf
1965 Corvair Chassis Shop Manual - SECTION 4 - REAR SUSPENSION
(3.39 MiB) Downloaded 28 times
Brad Bodie
Lake Chatuge, North Carolina
Image 1966 Corvair Corsa Convertible
lalkie01
Posts: 67
Joined: Sat Nov 16, 2019 2:02 pm

Re: Negative Camber/Urethane Bushings

Post by lalkie01 »

I never thought of taking pictures. I put in some black bushings that are harder. The grey ones were pretty soft. Not sure if I initially got the initial ones. The car rides much better and is more quite. The special washers part C395 from clarks were too thick to get in and they had a 3/8 hole as opposed to 1/2 hole. I put is some 1/25 inch flat washers and they were tight. Not sure how the special washers are expected to work. I have some minor adjustments and I will be driving again. Thanks Larry
User avatar
terribleted
Posts: 4584
Joined: Sun Apr 18, 2010 2:36 pm
Location: Atlanta, GA
Contact:

Re: Negative Camber/Urethane Bushings

Post by terribleted »

OK the stabilizer rods (small diameter rods toward the front of the rear suspension arms that mount on brackets on the front trans crossmember) have little or nothing to do with camber (by the way the bracket slide in and out on the trans crossmember...these brackets must be loose when adjusting camber at the strut rods). These little rods are where the C395 washers are used.

The large strut rods are what hold and adjust the camber. I have been assuming that you were talking about using urethane bushings in the strut rods? The special washers for the strut rods are C638X. They have a raised ring around the center hole that slips inside the sleeve of the bushing to keep the bolt centered and adjust the diameter of the sleeve down to the diameter of the bolt.The proper sleeve is C5788. The suspension will tend toward negative camber and be very sloppy without these washers as the bolts will slip all around inside the sleeves. You MUST use these special washers in the strut rod bushing sleeves! Flat washers will not work!! There are similar washers used in the front suspension at the lower inner control arm bushings also btw C4610. Like I said above improper assembly appears to be the issue. Study the shop manual and even Clark's diagrams to get it right.
Corvair guy since 1982. I have personally restored at least 20 Vairs, many of them restored ground up.
Currently working full time repairing Corvairs and restoring old cars.
https://www.facebook.com/tedsautorestoration/

Located in Snellville, Georgia
User avatar
bbodie52
Corvair of the Month
Corvair of the Month
Posts: 11897
Joined: Mon Aug 06, 2012 12:33 pm
Location: Lake Chatuge Hayesville, NC
Contact:

Re: Negative Camber/Urethane Bushings

Post by bbodie52 »

Brad Bodie
Lake Chatuge, North Carolina
Image 1966 Corvair Corsa Convertible
lalkie01
Posts: 67
Joined: Sat Nov 16, 2019 2:02 pm

Re: Negative Camber/Urethane Bushings

Post by lalkie01 »

The sleeves on the bushing I have run the full length of the bushing. I apparently ordered the wrong washers. As pictured the special washers would not work without cutting off the sleeves I have. The harder bushing did not squish out as I described which solved the negative camber when I adjusted it. I may have to make some changes. The flat washers may make the matter worse. I will have to look at it again. The special washers appear to fit inside the bushing. Do you know the diameter of the outside of the special washer? I appreciate the response. Larry
User avatar
terribleted
Posts: 4584
Joined: Sun Apr 18, 2010 2:36 pm
Location: Atlanta, GA
Contact:

Re: Negative Camber/Urethane Bushings

Post by terribleted »

Yes the special washers do have a raised center that inserts into the sleeves. These washers are essential for proper rear suspension operation. You need to order the correct parts (You need C638W sets of 4 washers) from Clark's or another source and install them.
Corvair guy since 1982. I have personally restored at least 20 Vairs, many of them restored ground up.
Currently working full time repairing Corvairs and restoring old cars.
https://www.facebook.com/tedsautorestoration/

Located in Snellville, Georgia
Post Reply

Return to “Ask your Mechanical Questions here”