69 Lwr Frt Control Arm Mount Specs
09-26-2011, 05:18 PM
#1
Racer
Thread Starter
69 Lwr Frt Control Arm Mount Specs
Does any one have dimensions for the lower front control arm mounting points on the front cross member?
I need to do a repair of the control arm mounting channel to cross member welds?
Center to center dimensions of the control arm shafts or mounting bolts front and rear and from the frame rails to control arms.
Thanks
I need to do a repair of the control arm mounting channel to cross member welds?
Center to center dimensions of the control arm shafts or mounting bolts front and rear and from the frame rails to control arms.
Thanks
09-26-2011, 06:21 PM
#2
Safety Car
I would look in the AIM (assemblty manual) first for those measurements. If they're not there, I'll try and get that info for you off of mine, but it'll take a couple days.
I assume it's torn or cracked? Give us some details, or better yet, pictures! I have a template for a weld-in reinforcement piece that solves the problem of the square block in the front mount cutting into the cross member. That is often where the cracks start.
Also, if this is all happening as I suspect it is, buy or make a spreader bar for the upper control mounts and solve other structural shortcomings with that.
Hans
I assume it's torn or cracked? Give us some details, or better yet, pictures! I have a template for a weld-in reinforcement piece that solves the problem of the square block in the front mount cutting into the cross member. That is often where the cracks start.
Also, if this is all happening as I suspect it is, buy or make a spreader bar for the upper control mounts and solve other structural shortcomings with that.
Hans
09-26-2011, 06:44 PM
#3
Racer
Thread Starter
None of the frame dimensions in AIM or that I found on line include where the front lower control arm mounting points should be.
The channel welds under the cross member are broken and the bracket that ties the channel to the back of the cross member is cracked in half.
I want move the channel back to the right place before I weld it back.
I think the front is ok.
Hans,
I would like to see your repair and template.
None of the posts I found included pictures of your fix or dimensions of the mounting points.
Thanks
The channel welds under the cross member are broken and the bracket that ties the channel to the back of the cross member is cracked in half.
I want move the channel back to the right place before I weld it back.
I think the front is ok.
Hans,
I would like to see your repair and template.
None of the posts I found included pictures of your fix or dimensions of the mounting points.
Thanks
09-26-2011, 07:16 PM
#4
Safety Car
Send an e-mail to hcabplanalp@ucdavis.edu and I'll send you the template and instructions. I may still have a photo of a finished repair, and I'll get those dimensions for you. I just parked mine in my folks garage, so I'll have to run out there and get it. My BOSS 302 is driving me crazy right now, so it'll be a couple of days.
Hans
Hans
10-04-2011, 08:02 PM
#5
Racer
Thread Starter
Lower control arm mounts breaking on a C3 is a common problem.
Can some one with access to a frame book please look up where the mounts should be.
Or if you have a frame with the body off please grab a tape measure and post a few measurements.
Can some one with access to a frame book please look up where the mounts should be.
Or if you have a frame with the body off please grab a tape measure and post a few measurements.
04-25-2018, 06:38 PM
#7
Cruising
thank you,
04-25-2018, 09:34 PM
#8
Racer
Thread Starter
The posts above is all the information I have.
I pried, hammered, jacked and clamped the channels back to approximately where I thought they came from and welded them in.
Welds that actually had penetration in the stock places and stitch welded on the sides.
Never did find out if they are supposed to be parallel or not or any official numbers.
Mine ended up closer in the rear about 1/8".
I pried, hammered, jacked and clamped the channels back to approximately where I thought they came from and welded them in.
Welds that actually had penetration in the stock places and stitch welded on the sides.
Never did find out if they are supposed to be parallel or not or any official numbers.
Mine ended up closer in the rear about 1/8".
04-25-2018, 10:35 PM
#9
Cruising
The posts above is all the information I have.
I pried, hammered, jacked and clamped the channels back to approximately where I thought they came from and welded them in.
Welds that actually had penetration in the stock places and stitch welded on the sides.
Never did find out if they are supposed to be parallel or not or any official numbers.
Mine ended up closer in the rear about 1/8".
I pried, hammered, jacked and clamped the channels back to approximately where I thought they came from and welded them in.
Welds that actually had penetration in the stock places and stitch welded on the sides.
Never did find out if they are supposed to be parallel or not or any official numbers.
Mine ended up closer in the rear about 1/8".
thank you,
04-29-2018, 12:23 PM
#11
Cruising
Thx.....i have been away from computer..... posting now....
Last edited by shannon1970; 04-29-2018 at 12:33 PM. Reason: failed to post pictures
04-29-2018, 08:49 PM
#12
Racer
Thread Starter
That does not look bad at all.
What part exactly are you concerned about?
It looks like normal crappy factory welds.
One small crack on pass top inside that is not likely to spread, everything still in place.
Are the other top corners of the rear braces cracked?
Are any of the slot welds between the lower channels cracked?
Take a good look all around the spring pockets, front cross member to frame, steering box, lower channel mounts and upper control arm mounts.
With the engine out is the time to fix any problems.
The hardest part is to get it clean enough to weld.
Pressure wash, wire brush and sweat the oil out of the laps and cracks with a torch.
Almost any one could run better welds than the factory and they lasted 50 years.
What part exactly are you concerned about?
It looks like normal crappy factory welds.
One small crack on pass top inside that is not likely to spread, everything still in place.
Are the other top corners of the rear braces cracked?
Are any of the slot welds between the lower channels cracked?
Take a good look all around the spring pockets, front cross member to frame, steering box, lower channel mounts and upper control arm mounts.
With the engine out is the time to fix any problems.
The hardest part is to get it clean enough to weld.
Pressure wash, wire brush and sweat the oil out of the laps and cracks with a torch.
Almost any one could run better welds than the factory and they lasted 50 years.
05-01-2018, 04:05 PM
#13
Cruising
That does not look bad at all.
What part exactly are you concerned about?
It looks like normal crappy factory welds.
One small crack on pass top inside that is not likely to spread, everything still in place.
Are the other top corners of the rear braces cracked?
Are any of the slot welds between the lower channels cracked?
Take a good look all around the spring pockets, front cross member to frame, steering box, lower channel mounts and upper control arm mounts.
With the engine out is the time to fix any problems.
The hardest part is to get it clean enough to weld.
These pics are from passenger side. This is what has me concerned......
Pressure wash, wire brush and sweat the oil out of the laps and cracks with a torch.
Almost any one could run better welds than the factory and they lasted 50 years.
What part exactly are you concerned about?
It looks like normal crappy factory welds.
One small crack on pass top inside that is not likely to spread, everything still in place.
Are the other top corners of the rear braces cracked?
Are any of the slot welds between the lower channels cracked?
Take a good look all around the spring pockets, front cross member to frame, steering box, lower channel mounts and upper control arm mounts.
With the engine out is the time to fix any problems.
The hardest part is to get it clean enough to weld.
These pics are from passenger side. This is what has me concerned......
Pressure wash, wire brush and sweat the oil out of the laps and cracks with a torch.
Almost any one could run better welds than the factory and they lasted 50 years.
Here is my concern.........
Last edited by shannon1970; 05-01-2018 at 04:09 PM. Reason: not my finished reply?
03-31-2023, 02:03 AM
#14
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Location: Gold Coast
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04-02-2023, 12:58 AM
#15
Old Pro Solo Guy
Looks like they were supposed to be parallel, but a survey show a lot of variation. That's the way the QC went in the 70s.
More shims are frequently added to the rear for caster, that part is normal.
What is important is that the shims stacks are pretty even on both sides.
Mine were not, below.
My car had been wrecked, frame was bent, and the right lower control arm mount was welded 3/8" off , at the factory, 50 years ago. The weird shim stacks corrected the alignment, but I still couldn't stand it. I took it to the frame shop. And I cut the one bracket off and welded on a new one, parallel this time.
04-12-2023, 05:02 AM
#16
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Thanks. I thought I took some pics, but I mustn't have. My arms were slightly closer at the rear (more castor) but the frame mounts are way off. One side has a roughly even amount of shims front and back, the other side has no shims at the front and half an inch of shims at the back to get the arm geometry back to where it needs to be.
