73 Vert jacking and supporting points

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Trident1

Member
Joined
Apr 23, 2014
Messages
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Location
united states
My Car
1973 Ford Mustang Convertible, Red w/ white 302-2v
Hello everyone. I have had the car a year. it is a 73 Convertible Red /White with a 302. I have been a "lurker" on the forum so far but have not posted anything since I have been simply getting used to the car and making my to-do list.

I have to do some (what seems to be typical maint repair) on the car so i jacked it up last weekend using the rear diff and put jack stands just forward of the leaf springs since I am replacing them. Then went and jacked up the front end and put the stands at the rear portion of the frame rails.

When walking back to the rear of the car, I noticed that the driver's door was 'slightly ajar' and when I went to open the door to close it, I couldn't. I noticed the gap was significant....and by significant I mean about 3/4 to 1 inch!

I immediately lowered the car back down off the jack stands and told myself I would never do that again. I did not realize that the car flexed THAT much.

So...where is the safest place to A) jack up a Vert and B) where are you supposed to support it with jack stands to minimize body flex and issues?

Thank you in advance for helping a Newbie.

 
Last edited by a moderator:
I am curious on this as well. I have a coupe but need to put it up on stands to do some work and am not sure of the bast place to put the stands either.

 
Welcome to the site.

Is there rust/ rot under the car ?

By end of the front frame rail - do you mean the short section

right before the seat platforms ?

If so that is not a good area as you were supporting the middle of the car. The front and rear overhangs were too much in that case.

There are many good jacking points - where you put the stands depends on the work you are doing.

Do a search on the site - pretty sure there is a jacking point diagram on here.

For doing the rear springs - I would support the rear like you did and leave the front on the ground.

Hope it was OK after you lowered it down

Don

 
Like Don suggests it sounds like you have severe rust that has made the car weak. Just think even if there are no holes but 50% of the metal has rusted away you lost 50% of the strength.

Just in front of the leaf springs in the rear should be the strongest point there. The front should be where the firewall cowl joins the floor at the A post or torque box. When these cars were new people cracked windshields by jacking up wrong and twisting the body. Never Nerver jack the front up by the front cross member. Just think about leverage the farther you are away from the weight the greater the leverage to bend the car. Never have the car without the shock tower braces installed except when you need to access valve covers or such.

If you look in the frame members you will see some larger holes in the bottom those were what was used to tool and weld the chassis and the car rode down the assembly line on those points. There is usually an area around the hole with no paint because they rode on the Buck to paint sitting on those areas.

You might need to do some repairs to the chassis. A frame shop can check the chassis using the Ford supplied measurements and you might need to "pull" the chassis back in shape. I have attached a scan from the Ford manual for the Chassis measurements. They have gages they hang in the check points and can measure accurately.

In the past one member was considering trying to get his side windows recut because they did not fit the windshield frame due to chassis bending.

I hear you saying you are changing the leaf springs. These cars sat low in the rear when new. You can have the current spring re-arched by a spring shop. They do not really wear out just get a little flat. When my 73 was new I put helper springs around the rear shocks to bring the rear up some also. This helped handling during autocross runs.

Rust never stops since these cars were not dipped into a vat of primer the insides of the frame members and rockers rust and never stop. You can buy kits of sprays to spray material inside to slow down the rust.

Good luck keep us posted on how it goes.

David

1973_Mustang_Cougar_Underbody_Dim.img.pdf

 

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Welcome lurker!

Since our convertibles don't have the roof support they tend to flex a little more. I put sub-frame connectors on mine a long time ago. It's the best thing you can do to help avoid the body flex.

 
Trident1, I wouldn't let this flex freek you out to much. I've worked on many convertibles over the last thirty years and if it's not rusting you can deal with this. For one don't open or close the doors if the gaps don't look right, you will just be chipping paint. If you must open the doors you can jack up the front or rear to get the gaps back to normal before opening or closing the doors. Never adjust the doors when on frame supported stands. Have it on the tires if possible. You can use eight stands if you want to support it evenly. That would four on the rear near the spring mounting points. Two at front torque boxes and two at the frame near the radiator support. I use screw stands on the most rear and furthest forward because you can get precise adjustments with them to get gaps right. It can be difficult on ratchet stands.

 
Welcome lurker!

Since our convertibles don't have the roof support they tend to flex a little more. I put sub-frame connectors on mine a long time ago. It's the best thing you can do to help avoid the body flex.
I also have sub frame connectors installed on mine. If I need to jack the car's rear end, I typically place the jack under the rear diff to raise it, then place the stands under the sub frame connectors, rather than the torque boxes.

For the front, it's usually right in the center of the front cross member to get it up evenly, but place the stands on the front frame rails near the torque boxes.

I can't recall ever jacking up one side or the other - I always do it in the middle bringing both sides up equally - mostly, because I'm lazy and don't want to run the jack any more than I must. ;) But, limiting the torsional stress on the unibody "frame" is always best.

Verts do flex a lot more than the coupes and fastbacks - a good rule of thumb is like judge pointed out: don't open the doors when you have the car jacked up. I've also always heard not to do major alignment/adjustment of body panels unless the car is on its tires or rigidly supported as he mentioned. The suspension places specific tension on the unibody "frame" (by design), so you want to make adjustments with that tension imposed.

 
Thank you everyone for the pointers and responses! I appreciate it!

I do have subframe connnectors on the list to be done. I agree after thinking about it that where I had the car supported was a bit too close to the center of the vehicle. Can you support the car under the rear axle to do rear suspension work (leaf springs, shocks etc)?

The car looks solid underneath. the only big rust is on the rear right quarter right behind the door (and by big rust I mean there are bubbles, but the paint isn't broken and doesn't give when pushed on with a thumb or anything.

So far my must do list includes: Transmission leak - from shifter seal, ball joints, tie rod ends, pitman arm and idler arm to tighten up steering, replace temp sensor, remove A/C(don't need or want in vert). Fix tear around rear window in top. and replace the lights behind speedo and duh-light cluster...found out last night they don't light up at night.

my want to do list are mostly cosmetic - add front spoiler, add Magnum 500s(7&8s) add tach to instrument cluster (right now the PO has a mini tach strapped to steering column...annoying as hell where it is.), clean up interior a bit (no tears, just cleaning of pieces etc. ) and finally add a Mach 1 hood....which would lead to getting car painted...

Looking forward to tapping the general experience of the forums on here(as well as share a few laughs at my DOH moments when i attempt to complete items) as I am pretty new to the classic muscle cars. Have played with european cars a little bit but nothing difficult. This seems to be a pretty straight forward vehicle to work on myself...hopefully

.

 
Can you support the car under the rear axle to do rear suspension work (leaf springs' date=' shocks etc)?[/quote']
It kinda depends on what you want to do. Shocks? Yes. Just gotta stuff the shocks up under the rear shock crossmember and "aim them" toward the lower shock mounts on the axle spring retainers before cutting the straps. Leaf springs? Not so much. For the leaf springs, you'll need to elevate and support the car, allowing the rear axle to droop and relax tension off the springs so you can work with them. Having the jack stands anywhere near the springs will create interference and be a major PITA. Best bet is to chock the front wheels and put the jack stands under the rear torque boxes.

...add tach to instrument cluster (right now the PO has a mini tach strapped to steering column...annoying as hell where it is...
Go with a Rocketman tach conversion - looks sweet, factory, and even re-purposes your "duh light" gauge in the cluster.

Here's the latest "believer." ;)

http://www.7173mustangs.com/thread-rocketmans-tach-conversion-rocks-in-renewed-dash
 
Thank you everyone for the pointers and responses! I appreciate it!

I do have subframe connnectors on the list to be done. I agree after thinking about it that where I had the car supported was a bit too close to the center of the vehicle. Can you support the car under the rear axle to do rear suspension work (leaf springs, shocks etc)?

The car looks solid underneath. the only big rust is on the rear right quarter right behind the door (and by big rust I mean there are bubbles, but the paint isn't broken and doesn't give when pushed on with a thumb or anything.

So far my must do list includes: Transmission leak - from shifter seal, ball joints, tie rod ends, pitman arm and idler arm to tighten up steering, replace temp sensor, remove A/C(don't need or want in vert). Fix tear around rear window in top. and replace the lights behind speedo and duh-light cluster...found out last night they don't light up at night.

my want to do list are mostly cosmetic - add front spoiler, add Magnum 500s(7&8s) add tach to instrument cluster (right now the PO has a mini tach strapped to steering column...annoying as hell where it is.), clean up interior a bit (no tears, just cleaning of pieces etc. ) and finally add a Mach 1 hood....which would lead to getting car painted...

Looking forward to tapping the general experience of the forums on here(as well as share a few laughs at my DOH moments when i attempt to complete items) as I am pretty new to the classic muscle cars. Have played with european cars a little bit but nothing difficult. This seems to be a pretty straight forward vehicle to work on myself...hopefully

.
For leaf springs you want to support the back like you did before.

Then either leave the front on the ground

Or jack it up by the cross member and support it in the front - under the frame rails [ at front of the car ] or right at the pivot point of the control arm usually works good for me. You can also jack each side up in the front using the control arm.

 
Thank you very much everyone! I like the idea of doing the weld on sub-frame connectors vs bolt on, seems like they would do the job better.

The tach idea is a little lower on the list but love the look of it vs the plain gauges.

Will have to go over and spend some money at Ohio Mustang Supply seeing that they are in the neighborhood...

 
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