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Stiff LM idler arm
Posted by: Chasgee ()
Date: September 13, 2020 03:37PM

Hello all,

I recently rebuilt the steering system on my LM. The idler arm was really stiff when I installed it. The post that bolts to the frame is the stiff joint. I’ve been driving it around a while and expected it to get a little looser but it doesn’t seem to be getting any better. It is so stiff that the front wheels won’t self center when turning. It will also stick in various positions and I have to give the wheel a good tank to get it centered. Everything moves freely when I disconnect it from the frame.

Obviously this can’t be normal. Should I be more patient and let it wear in or just replace it? It is a new part that cane with the car when I bought it a few years ago.

Chuck Gee
Carlsbad, CA

1963 Monza 102 - in the family from new - Sold
1966 Corsa 140 Coupe

Re: Stiff LM idler arm
Posted by: RobertC ()
Date: September 13, 2020 03:49PM

New LM idler arms have always been stiff to me.

Since you rebuilt the suspension, have you had the car 4 wheel aligned?

Return to center is a factor how much caster the suspension has. Again, since you rebuilt the suspension, maybe this value has changed.

I have used +3 degrees on my LMs.

Edited 1 time(s). Last edit at 09/13/2020 03:49PM by RobertC.

Re: Stiff LM idler arm
Posted by: TerribleTed ()
Date: September 13, 2020 04:34PM

During rebuild did you replace the pitman arm bushing with a nylon one (installed by Clark's or otherwise)? The idler arms are fairly stiff but I have never had one keep the steering from centering (alignment must be right of course). I have found that fairly often the nylon pitman arm bushings are too tight against their bolt. (you can check this by taking separating the pitman arm from the drag link and trying to turn the bolt in the bushing with a 5/8 wrench. It should turn readily with a little resistance only. If it is tighter than snug it is too tight. Fix is to remove the bolt from the bushing and sand the inside of the bushing with fine sandpaper (180 grit max and finish with 320 grit or so) until the bolt is a snug slip fit that can be turned easily with a 5/8 wrench. I use sticky backed sandpaper on a small deep socket chucked into a drill or air ratchet to ream the bushings when they are too tight


Avid Corvair hobbiest since 1984.
I have personally performed ground up restoration on over 20 Corvairs.
I currently work full time at restoring and repairing Corvairs.
Located in the Atlanta Georgia area.

Re: Stiff LM idler arm
Posted by: Chasgee ()
Date: September 13, 2020 04:48PM

I just had it aligned after I rebuilt everything. The caster is 4 degrees. I figured that would fix the problem but it didn’t.

I’ll check the pitman arm bushing. The steering does move freely if I disconnect the idler from the frame so I’m guessing the pitman arm bushing isn’t too tight. I’ll double check anyway.

Re: Stiff LM idler arm
Posted by: Wagon Master ()
Date: September 13, 2020 05:56PM


'29 Ford Model A Tudor
'61 700 Lakewood 110 4 speed
'69 Monza Convert. 140 Auto.
'70 Dodge Challenger R/T 440 4 speed

Been aircooled since 1973
Northwest Ohio

Re: Stiff LM idler arm
Posted by: Chasgee ()
Date: September 13, 2020 06:19PM

Yes positive 4 degrees.

Re: Stiff LM idler arm
Posted by: 66vairman ()
Date: September 13, 2020 06:37PM

The new idler arms I've seen have a grease fitting. Try adding some grease.

T Ted summed it up well. Your idler arm should be snug to move, but not require excess effort.

BTW - caster is sensitive to tire width and wheel offset. If you aren't running stock rims and tires that might be part of the "doesn't want to self center" issue.

Re: Stiff LM idler arm
Posted by: American Mel ()
Date: September 13, 2020 06:53PM

Ted is correct.
That Nylon bushing is the WRONG size ! ! !
It will be too tight, and not automatically come to center, unless you ream it out.
or just drive down a LOT of twisting turns, and wear it to size. grinning smiley

WA. state, 1 mile south of the Canadian border,
I am not at the end of the world, but you can see it from here.
Have; '66 Monza Coupe - 140, 4-spd. Daily driver beater
'67 Monza Vert. - 140, 4-spd. Daily driver beater
'67 A/C Moredoor Monza
Have had; '61 Monza coupe, 80hp, PG
'62 Monza Wagon, 4spd.
'63 Spyder,
'65 Corsa
'04 Dodge Cummins Quad Dually, approaching 400K
'03 Honda Del Sol

Re: Stiff LM idler arm
Posted by: BobV66Vair ()
Date: September 14, 2020 07:04AM

Disconnect the idler arm and see how stiff it is. You should be able to move it by hand. If that's not the problem, check the pitman arm bushing the same way. Harder but pull the pitman arm and see how stiff the bushing are. I had to ream mine to get it to turn easily.

Bob Vinnacombe
Sandy, Oregon
1965 Corsa 140 stock
1966 Monza Soon to be race car
1968 Monza Parts for now

Re: Stiff LM idler arm
Posted by: corventure Dave ()
Date: September 14, 2020 12:43PM

By the way. Did they do a 4wheel alignment or a 5 wheel alignment?
Many shops forget the steering wheel.

I'm also leaning towards the pitman arm bushing being too tight.

Corventure Dave

Re: Stiff LM idler arm
Posted by: 66vairman ()
Date: September 14, 2020 06:21PM

Maybe I've just been unlucky with the nylon pitman arm bushings going bad.

I went back to the original style rubber pitman arm bushing molded in the shell and have had no issues. Steering feel is no different vs. the nylon bushing. I can't see a reason to use the nylon bushing since it seems inferior to the original part design. Just me.

Re: Stiff LM idler arm
Posted by: jjohnsonjo ()
Date: September 14, 2020 06:28PM

I don't think mine ever came back to center as well as when I had the OEM type. I think the rubber helps to pull it back.


65 Corsa Turbo Vert
79 Honda XL 500S
69 Honda CL 160 D
2010 BMW F 650 GS
2003 Bounder 36D
2013 KIA Optima SX turbo-AKA ZIPPY (wife,s car)
69 Newport Holiday Sailboat
Baja 150 dune buggy cart
Coleman HS 500 UTV
2016 KIA Sorento SXL Turbo


Re: Stiff LM idler arm
Posted by: dryenko ()
Date: September 15, 2020 04:03AM

If the bushing is too tight, you can help it wear in.
By assembling with some valve grinding compound on the bolt and inside the bushing
And then drive the car.
When the steering binding goes away, removed the bolt and clean the mating parts.
It helps to use anti-seize initially on the taper on the bolt to facilitate this operation.

Bob C aka Dryenko
Dobson, NC 27017

Re: Stiff LM idler arm
Posted by: RexJohnson ()
Date: September 15, 2020 07:08PM

The rubber bushing does help center the wheel if it is tightened up with the wheels straight ahead. As with all rubber bushing they need to be tightened in their normal centered position or ride height.

RJ tools

Re: Stiff LM idler arm
Posted by: vairmech ()
Date: September 16, 2020 05:18AM

If you really suspect the nylon bushing as being to tight I always polish the bolt and then run a 9/16" drill bit through the bushing. Use a urethane bushing grease and all should be well.

Also, I have replaced a couple of late idler arms and one I had to change because the idler arm was absolutely to tight! The steering was stiff would not return to center and even hard to drive straight down the road. I changed out the idler with an NOS one I have an the steering returned to normal.

Ken Hand
Handy Car Care
248 613 8586

Re: Stiff LM idler arm
Posted by: Jonathan Knapp ()
Date: September 17, 2020 09:29PM

I drilled and fitted a grease fitting in my idler arm joint. That loosened it up considerably. Previously it was very stiff and crunchy. I soaked it in solvent and blew it dry with compressed air through the new hole before greasing it.

Jonathan Knapp
Wheeling, WV
'66 Corsa Autocrosser

Re: Stiff LM idler arm
Posted by: Chasgee ()
Date: September 19, 2020 02:34PM

OK, I finally got some time to work on this. Turns out it was the pitman arm bushing! The bolt was so tight I had to use a puller in reverse to get it out of the nylon bushing. I’m surprised the car turned at all.

I reamed the bushing so the bolt moves freely but still a little snug. Greased it up and reassembled. The steering now works as it should!

Thanks to all for your help with this!

Chuck Gee
Carlsbad, CA

1963 Monza 102 - in the family from new - Sold
1966 Corsa 140 Coupe

Re: Stiff LM idler arm
Posted by: MattNall ()
Date: September 19, 2020 03:20PM


Sea Mountain, between Charleston Harbor and Coos Bay! SW Oregon Coast
Click HERE for My Website...Click HERE for My TechPages!

Re: Stiff LM idler arm
Posted by: vairmech ()
Date: September 20, 2020 05:20PM

Glad it was an easy fix.

Ken Hand
Handy Car Care
248 613 8586

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