Someone please explain to me..
Thread Starter
Burning Brakes
Joined: Apr 2005
Posts: 1,227
Likes: 0
From: Atlanta Ga
Someone please explain to me..
what the shims with the body mounts are for. Just what are you shimming? How does one know BEFORE the body is put back on how much shmming is needed? What does the use or lack of use effect
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
Did you happen to note how many were in place and which mounts they were on? That's how I would assume to get them back in.
If the body looks off a bit, pull out the bolt, jack up the body there, and insert a new shim. You don't have to tighten any of the bolts until the body sits just right.
Thread Starter
Burning Brakes
Joined: Apr 2005
Posts: 1,227
Likes: 0
From: Atlanta Ga
Did you happen to note how many were in place and which mounts they were on? That's how I would assume to get them back in.
If the body looks off a bit, pull out the bolt, jack up the body there, and insert a new shim. You don't have to tighten any of the bolts until the body sits just right.
If the body looks off a bit, pull out the bolt, jack up the body there, and insert a new shim. You don't have to tighten any of the bolts until the body sits just right.
you said "If the body looks off a bit" what does that mean?
looks off how?
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
If you look at the car and something doesn't sit right...you know...looks uneven? Or just measure the wheel wells to the floor. If any of the corners sit a little higher or lower than the rest use the body mount shims.
I'm just guessing as I have never done this...but that seems how it would go.
Burning Brakes
Joined: Jul 2006
Posts: 943
Likes: 3
From: Chicago IL
Did you happen to note how many were in place and which mounts they were on? That's how I would assume to get them back in.
If the body looks off a bit, pull out the bolt, jack up the body there, and insert a new shim. You don't have to tighten any of the bolts until the body sits just right.
If the body looks off a bit, pull out the bolt, jack up the body there, and insert a new shim. You don't have to tighten any of the bolts until the body sits just right.
Is this something you can eyeball or would you use some kind of level to read how true it was once the shims were added or removed? I suppose you would have to be certain the car sat correct to begin with. When the body work was done on mine, I had Goat tell me he had to do something similar in order to get the correct look. He used some kind of leveler on the frame and body. Oh well, I thought I would through that in there anyway.
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
DB,
Is this something you can eyeball or would you use some kind of level to read how true it was once the shims were added or removed? I suppose you would have to be certain the car sat correct to begin with. When the body work was done on mine, I had Goat tell me he had to do something similar in order to get the correct look. He used some kind of leveler on the frame and body. Oh well, I thought I would through that in there anyway.
Is this something you can eyeball or would you use some kind of level to read how true it was once the shims were added or removed? I suppose you would have to be certain the car sat correct to begin with. When the body work was done on mine, I had Goat tell me he had to do something similar in order to get the correct look. He used some kind of leveler on the frame and body. Oh well, I thought I would through that in there anyway.
Like I said...I would just measure the body opening to the frame and floor. Get it as even as you can using those two points. I would also do it by side, front and then rear.
Melting Slicks
Joined: Apr 2004
Posts: 2,008
Likes: 38
From: Space Coast Gator Territory
It is best if you can measure the thickness of the shims you take out with a caliper and record the data. This way you can shim the new mount set similairly. Due to rust issues, this is not always easily done.
If you need to start from scratch, set yopur body on the frame with mounts and one shim on four of the eight mounting locations. From this point, shim those four so the body looks right over the wheels and there is no rocking. Pay attention to the door gaps, they will tell you if the #2-3 shims are right. After this is done, use a lump of clay to help measure the space you need to shim on the remaining four mounts. Measure the clay with your caliper and add a corresponding number of shims. You will know if you got it right when you tighten the mount bolts. If your door gap closes or opens, it means you need to add or remove shims. If you started leveling the body with #'s 1-4, you will only need to play with #'s 2-3 in this process.
Common sense tells you not to be carrying weight or walking inside the car during this process. Cars not well supported while the body is off will likely have problems shiming the body later, things move. When precautions are taken, it saves work later.
If you need to start from scratch, set yopur body on the frame with mounts and one shim on four of the eight mounting locations. From this point, shim those four so the body looks right over the wheels and there is no rocking. Pay attention to the door gaps, they will tell you if the #2-3 shims are right. After this is done, use a lump of clay to help measure the space you need to shim on the remaining four mounts. Measure the clay with your caliper and add a corresponding number of shims. You will know if you got it right when you tighten the mount bolts. If your door gap closes or opens, it means you need to add or remove shims. If you started leveling the body with #'s 1-4, you will only need to play with #'s 2-3 in this process.
Common sense tells you not to be carrying weight or walking inside the car during this process. Cars not well supported while the body is off will likely have problems shiming the body later, things move. When precautions are taken, it saves work later.
Melting Slicks
Joined: Mar 2002
Posts: 2,140
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From: Ohio
I have done this and put two shims under the #2 and #3 mounts. Shim #4 mounts till the door gap is the same at the top and bottom in the rear on verts. Shim #1 and the radiator support till the hood fits. The best way is to watch when you remove the body and put the same amount back in each location.
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I have done this and put two shims under the #2 and #3 mounts. Shim #4 mounts till the door gap is the same at the top and bottom in the rear on verts. Shim #1 and the radiator support till the hood fits. The best way is to watch when you remove the body and put the same amount back in each location.
Melting Slicks
Joined: Aug 2006
Posts: 3,429
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From: Kingston Ontario
Ok, here's one
I'm using a 73 body and frame for my 72 which originally had aluminum pucks. I'm switching to rubber mounts, would the 72 front clip sit lower than the 73's original? Whats the process for that?
Le Mans Master
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At the factory they sat the body on top of the chassis & would go to each mounting point and look for gaps. They would fill the gap with as many shims as needed...........
Melting Slicks
Joined: Mar 2002
Posts: 2,140
Likes: 7
From: Ohio
BB72
I have read that when the 73's came out with rubber mounts many eariler sharks were changed to the rubber mounts so it must have been just a switch them out deal. I would like to know how the front horns on the 73 frame fit a 72. I have a 74 frame to put under a 72 and know I need to change the rear parts but would like to know about the front.
I have read that when the 73's came out with rubber mounts many eariler sharks were changed to the rubber mounts so it must have been just a switch them out deal. I would like to know how the front horns on the 73 frame fit a 72. I have a 74 frame to put under a 72 and know I need to change the rear parts but would like to know about the front.
Drifting
Joined: Jul 2006
Posts: 1,871
Likes: 6
From: Sault Ste. Marie Ontario
Try to find a 72 and 73 frame dimension drawing and do a comparson check on the dimensions from datum to the top of the mounts. I believe in 73 they lowered the mounts slightly (approx 3/8"??) to accommodate the rubber mount.
Melting Slicks
Joined: Jun 2005
Posts: 2,293
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From: North of the Bay California
The poly mounts are taller. There was a thread about how to reduce the height using a belt sander and pvc pipe-excellent write up.
Something else to consider, if you are using the wheel well as a measurement for alignment, the gaps might change if you change anything in the suspension
Instructor
Joined: Aug 2005
Posts: 234
Likes: 0
From: Covington, Virginia
One of the most important things to remember about body mounts/shims and fiberglass cars??? They used jig assembly for some parts and hand assembly for others. The bottoms of the cars (where the body sits on the frame) had a fair amount of variation, unlike the welded sheetmetal of other cars that fit pretty well most all of the time. When the bodies were mated to the frames, they didn't pull the fiberglass down to meet the mount, they added a shim to take up the slack. If you put the mounts where they are supposed to be, set the body in place and then drop a bolt down thru all of that to keep it kinda lined up.....you can then go to each mount that has space between the mount and the body and add the appropriate amount of shim to eliminate the space. Good Luck
Melting Slicks
Joined: Mar 2002
Posts: 2,140
Likes: 7
From: Ohio
At the factory the body was put in a jig that told the workers the number of shims at each location. The proof of this is the chalk marks on the side of the frame at each body mount had a number or marks to tell how many shims was needed.
Team Owner
Joined: Jun 2000
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From: Southbound
Cruise-In II Veteran
Check your frame for factory shim marks near each body mount. During assembly they used a machine on the frame which measured the mounts and determined the number of shims to be used at each location. This number was written on the frame at each mount in grease pencil. Probably arabic numbers on your car, but could also be hash marks.
Note the "4" on the frame near #1 mount. #2 is also marked, but I can't read it from this angle.
Note the "4" on the frame near #1 mount. #2 is also marked, but I can't read it from this angle.
Melting Slicks
Joined: Aug 2006
Posts: 3,429
Likes: 20
From: Kingston Ontario
BB72
I have read that when the 73's came out with rubber mounts many eariler sharks were changed to the rubber mounts so it must have been just a switch them out deal. I would like to know how the front horns on the 73 frame fit a 72. I have a 74 frame to put under a 72 and know I need to change the rear parts but would like to know about the front.
I have read that when the 73's came out with rubber mounts many eariler sharks were changed to the rubber mounts so it must have been just a switch them out deal. I would like to know how the front horns on the 73 frame fit a 72. I have a 74 frame to put under a 72 and know I need to change the rear parts but would like to know about the front.
