Shimming body mounts to decrease door gaps
Thread Starter
Drifting
Joined: Dec 2007
Posts: 1,309
Likes: 24
From: Coastal Georgia
C2 of the Year Finalist - Modified 2020
Shimming body mounts to decrease door gaps
Last summer I began the process of putting a '67 convertible back together from a pile of parts. The car had been in a collision, and the repaired body was placed loosely on a different frame while it was painted and the original frame was straightened. I ultimately decided to use the frame that the car was already sitting on because its condition and supporting components were in much better shape than the original. The first thing that I did to the car was to replace all the body mounts.
Because the car was only loosely placed on the frame, only a couple mount bolts were in place on each side, and there were no shims to be found. I tried to shim the body appropriately as I went, but to be honest, I hardly knew what I was doing at that point. I don't think I ended up with more than a couple shims at any one place on the body.
Fast forward to today, when vast progress on the car has been made. The entire engine bay has been completed, and the car actually runs now. I also have about 80% of the interior installed as well. The next project on the car was to get the doors squared away...they needed considerable restoration on the internal components, and had only been loosely installed with about 4 bolts each on the hinges after paint. I've spent several hours working on the gaps, and I've finally gotten pretty decent at getting the doors lined up equally front and back, but that leads me to my problem...
My door gaps on the leading edge as well as the rear edge are huge. Like around 3/8" all the way around. I know the factory spec is 1/8-1/4", but no matter which way I move the doors, I can't get the gaps any smaller, even though the door is perfectly centered in the opening. I installed new weatherstripping on the doors, and the gaps are so big that the weatherstripping doesn't even seal up in some places.
The only thing I can think of to do is revisit shimming some of the body mounts to try to close the gaps up a bit. Should I look at the #1 and #5 mounts first, or do I need to add shims all around? Also, I'm assuming I should shim one side at a time to get a perfect fit for each door? The gaps on both sides measure out the exact same, so I'm not sure if I should add the same amount of shims to each side or not...
Any advice would be greatly appreciated. Thanks in advance.
Because the car was only loosely placed on the frame, only a couple mount bolts were in place on each side, and there were no shims to be found. I tried to shim the body appropriately as I went, but to be honest, I hardly knew what I was doing at that point. I don't think I ended up with more than a couple shims at any one place on the body.
Fast forward to today, when vast progress on the car has been made. The entire engine bay has been completed, and the car actually runs now. I also have about 80% of the interior installed as well. The next project on the car was to get the doors squared away...they needed considerable restoration on the internal components, and had only been loosely installed with about 4 bolts each on the hinges after paint. I've spent several hours working on the gaps, and I've finally gotten pretty decent at getting the doors lined up equally front and back, but that leads me to my problem...
My door gaps on the leading edge as well as the rear edge are huge. Like around 3/8" all the way around. I know the factory spec is 1/8-1/4", but no matter which way I move the doors, I can't get the gaps any smaller, even though the door is perfectly centered in the opening. I installed new weatherstripping on the doors, and the gaps are so big that the weatherstripping doesn't even seal up in some places.
The only thing I can think of to do is revisit shimming some of the body mounts to try to close the gaps up a bit. Should I look at the #1 and #5 mounts first, or do I need to add shims all around? Also, I'm assuming I should shim one side at a time to get a perfect fit for each door? The gaps on both sides measure out the exact same, so I'm not sure if I should add the same amount of shims to each side or not...
Any advice would be greatly appreciated. Thanks in advance.
Drifting
Joined: Apr 2001
Posts: 1,401
Likes: 9
From: Holly Springs, Nort Cackalacky / Jupiter, Florida
This is what I have from my notes on this subject.
To mount the body to the frame, install the body mount bolts, washers, shims, nuts, etc. on the six (6) body mounts that surround the passenger compartment. These six (6) adjustments that you need to be concerned with are #2 left and right, #3 left and right and #4 left and right. Start with a minimum number of shims, which is either three or four at each mount. Hold them in place with masking tape and align them for the mounting holes. Lower the body onto the frame. Correct placement for parts is shown in the Assembly Instruction Manual (AIM) (UPC 1Asm, sheet G1, item #2).
Tighten these six body mount bolts to be firm, just a little more than finger tight. Look closely at the shims at each of the six locations. The weight of the body should hold each stack of shims solidly in place. If any of the shims have spaces, remove the bolts and add shims as required. Replace the bolts and again firmly tighten all six bolts.
The bolts are slowly tightened until two things happen: the six bolts are evenly adjusted, but are all quite tight, and there are no gaps between the shims. These are the ideal body mounting conditions for the mounts around the passenger compartment.
The doors are installed next. Each door hinge has six bolts and there are a number of shims at each hinge, varying from none to six. Getting the doors adjusted can be rather difficult. There are two vertical gaps, one at the front of the door and one at the rear. The goal is to get both door gaps even. The front door gap is changed by adjusting the shims on the front mounts, #1 right and left, under the radiator support. Adding shims to mount #1 closes the front door gap at the top.
Each corner of the body is adjusted with more or fewer shims under the four corner body mounts. These are #1 left and right and #5 left and right. If the doors adjust properly, you're done. Some body work may be required for a perfect fit and you may have to adjust the doors a few more times.
Expect this whole procedure to take quite a bit of time.
Hope this helps,
RK
To mount the body to the frame, install the body mount bolts, washers, shims, nuts, etc. on the six (6) body mounts that surround the passenger compartment. These six (6) adjustments that you need to be concerned with are #2 left and right, #3 left and right and #4 left and right. Start with a minimum number of shims, which is either three or four at each mount. Hold them in place with masking tape and align them for the mounting holes. Lower the body onto the frame. Correct placement for parts is shown in the Assembly Instruction Manual (AIM) (UPC 1Asm, sheet G1, item #2).
Tighten these six body mount bolts to be firm, just a little more than finger tight. Look closely at the shims at each of the six locations. The weight of the body should hold each stack of shims solidly in place. If any of the shims have spaces, remove the bolts and add shims as required. Replace the bolts and again firmly tighten all six bolts.
The bolts are slowly tightened until two things happen: the six bolts are evenly adjusted, but are all quite tight, and there are no gaps between the shims. These are the ideal body mounting conditions for the mounts around the passenger compartment.
The doors are installed next. Each door hinge has six bolts and there are a number of shims at each hinge, varying from none to six. Getting the doors adjusted can be rather difficult. There are two vertical gaps, one at the front of the door and one at the rear. The goal is to get both door gaps even. The front door gap is changed by adjusting the shims on the front mounts, #1 right and left, under the radiator support. Adding shims to mount #1 closes the front door gap at the top.
Each corner of the body is adjusted with more or fewer shims under the four corner body mounts. These are #1 left and right and #5 left and right. If the doors adjust properly, you're done. Some body work may be required for a perfect fit and you may have to adjust the doors a few more times.
Expect this whole procedure to take quite a bit of time.
Hope this helps,
RK
Thread Starter
Drifting
Joined: Dec 2007
Posts: 1,309
Likes: 24
From: Coastal Georgia
C2 of the Year Finalist - Modified 2020
They are slightly larger at the top of the rear edge than at the bottom. The fronts are equal all around.
Thread Starter
Drifting
Joined: Dec 2007
Posts: 1,309
Likes: 24
From: Coastal Georgia
C2 of the Year Finalist - Modified 2020
This is what I have from my notes on this subject.
To mount the body to the frame, install the body mount bolts, washers, shims, nuts, etc. on the six (6) body mounts that surround the passenger compartment. These six (6) adjustments that you need to be concerned with are #2 left and right, #3 left and right and #4 left and right. Start with a minimum number of shims, which is either three or four at each mount. Hold them in place with masking tape and align them for the mounting holes. Lower the body onto the frame. Correct placement for parts is shown in the Assembly Instruction Manual (AIM) (UPC 1Asm, sheet G1, item #2).
Tighten these six body mount bolts to be firm, just a little more than finger tight. Look closely at the shims at each of the six locations. The weight of the body should hold each stack of shims solidly in place. If any of the shims have spaces, remove the bolts and add shims as required. Replace the bolts and again firmly tighten all six bolts.
The bolts are slowly tightened until two things happen: the six bolts are evenly adjusted, but are all quite tight, and there are no gaps between the shims. These are the ideal body mounting conditions for the mounts around the passenger compartment.
The doors are installed next. Each door hinge has six bolts and there are a number of shims at each hinge, varying from none to six. Getting the doors adjusted can be rather difficult. There are two vertical gaps, one at the front of the door and one at the rear. The goal is to get both door gaps even. The front door gap is changed by adjusting the shims on the front mounts, #1 right and left, under the radiator support. Adding shims to mount #1 closes the front door gap at the top.
Each corner of the body is adjusted with more or fewer shims under the four corner body mounts. These are #1 left and right and #5 left and right. If the doors adjust properly, you're done. Some body work may be required for a perfect fit and you may have to adjust the doors a few more times.
Expect this whole procedure to take quite a bit of time.
Hope this helps,
RK
To mount the body to the frame, install the body mount bolts, washers, shims, nuts, etc. on the six (6) body mounts that surround the passenger compartment. These six (6) adjustments that you need to be concerned with are #2 left and right, #3 left and right and #4 left and right. Start with a minimum number of shims, which is either three or four at each mount. Hold them in place with masking tape and align them for the mounting holes. Lower the body onto the frame. Correct placement for parts is shown in the Assembly Instruction Manual (AIM) (UPC 1Asm, sheet G1, item #2).
Tighten these six body mount bolts to be firm, just a little more than finger tight. Look closely at the shims at each of the six locations. The weight of the body should hold each stack of shims solidly in place. If any of the shims have spaces, remove the bolts and add shims as required. Replace the bolts and again firmly tighten all six bolts.
The bolts are slowly tightened until two things happen: the six bolts are evenly adjusted, but are all quite tight, and there are no gaps between the shims. These are the ideal body mounting conditions for the mounts around the passenger compartment.
The doors are installed next. Each door hinge has six bolts and there are a number of shims at each hinge, varying from none to six. Getting the doors adjusted can be rather difficult. There are two vertical gaps, one at the front of the door and one at the rear. The goal is to get both door gaps even. The front door gap is changed by adjusting the shims on the front mounts, #1 right and left, under the radiator support. Adding shims to mount #1 closes the front door gap at the top.
Each corner of the body is adjusted with more or fewer shims under the four corner body mounts. These are #1 left and right and #5 left and right. If the doors adjust properly, you're done. Some body work may be required for a perfect fit and you may have to adjust the doors a few more times.
Expect this whole procedure to take quite a bit of time.
Hope this helps,
RK
Race Director
Joined: Jan 2003
Posts: 17,638
Likes: 3,651
From: Central Arkansas
Then some additional shims in the rear most body mount should close the gap at the top. After that you will have to live with shifting the doors back or forward in the body opening to get the gaps about equal. I would start with one more shim in the rear and if that doesn't even up the rear gap try one more.
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Drifting
Joined: Nov 2003
Posts: 1,680
Likes: 68
From: Towanda KS
Your only option to decrease the door gaps you describe is to add material to the door edge or the door jam. I would adjust the gap to an acceptable uniform gap along the rear edge and then make note of the amount of material you need to add to the front hinge pillar to close up the gap.
When the door is removed, you can build up the hinge pillar with fiberglass cloth and resin and then grind to smooth and straighten to create an even gap with the front edge of your door.
You will need to replace and remove your door several times before you get this the way you want it.
tc
When the door is removed, you can build up the hinge pillar with fiberglass cloth and resin and then grind to smooth and straighten to create an even gap with the front edge of your door.
You will need to replace and remove your door several times before you get this the way you want it.
tc
Team Owner
Joined: May 2006
Posts: 37,594
Likes: 1,099
From: CA
Last summer I began the process of putting a '67 convertible back together from a pile of parts. The car had been in a collision, and the repaired body was placed loosely on a different frame while it was painted and the original frame was straightened. I ultimately decided to use the frame that the car was already sitting on because its condition and supporting components were in much better shape than the original. The first thing that I did to the car was to replace all the body mounts.
Because the car was only loosely placed on the frame, only a couple mount bolts were in place on each side, and there were no shims to be found. I tried to shim the body appropriately as I went, but to be honest, I hardly knew what I was doing at that point. I don't think I ended up with more than a couple shims at any one place on the body.
Fast forward to today, when vast progress on the car has been made. The entire engine bay has been completed, and the car actually runs now. I also have about 80% of the interior installed as well. The next project on the car was to get the doors squared away...they needed considerable restoration on the internal components, and had only been loosely installed with about 4 bolts each on the hinges after paint. I've spent several hours working on the gaps, and I've finally gotten pretty decent at getting the doors lined up equally front and back, but that leads me to my problem...
My door gaps on the leading edge as well as the rear edge are huge. Like around 3/8" all the way around. I know the factory spec is 1/8-1/4", but no matter which way I move the doors, I can't get the gaps any smaller, even though the door is perfectly centered in the opening. I installed new weatherstripping on the doors, and the gaps are so big that the weatherstripping doesn't even seal up in some places.
The only thing I can think of to do is revisit shimming some of the body mounts to try to close the gaps up a bit. Should I look at the #1 and #5 mounts first, or do I need to add shims all around? Also, I'm assuming I should shim one side at a time to get a perfect fit for each door? The gaps on both sides measure out the exact same, so I'm not sure if I should add the same amount of shims to each side or not...
Any advice would be greatly appreciated. Thanks in advance.
Because the car was only loosely placed on the frame, only a couple mount bolts were in place on each side, and there were no shims to be found. I tried to shim the body appropriately as I went, but to be honest, I hardly knew what I was doing at that point. I don't think I ended up with more than a couple shims at any one place on the body.
Fast forward to today, when vast progress on the car has been made. The entire engine bay has been completed, and the car actually runs now. I also have about 80% of the interior installed as well. The next project on the car was to get the doors squared away...they needed considerable restoration on the internal components, and had only been loosely installed with about 4 bolts each on the hinges after paint. I've spent several hours working on the gaps, and I've finally gotten pretty decent at getting the doors lined up equally front and back, but that leads me to my problem...
My door gaps on the leading edge as well as the rear edge are huge. Like around 3/8" all the way around. I know the factory spec is 1/8-1/4", but no matter which way I move the doors, I can't get the gaps any smaller, even though the door is perfectly centered in the opening. I installed new weatherstripping on the doors, and the gaps are so big that the weatherstripping doesn't even seal up in some places.
The only thing I can think of to do is revisit shimming some of the body mounts to try to close the gaps up a bit. Should I look at the #1 and #5 mounts first, or do I need to add shims all around? Also, I'm assuming I should shim one side at a time to get a perfect fit for each door? The gaps on both sides measure out the exact same, so I'm not sure if I should add the same amount of shims to each side or not...
Any advice would be greatly appreciated. Thanks in advance.
If it's not 'sealing' as you say, you got some major body work to redo in/on your doors or your seals are put on wrong...
My 2cents.
Thread Starter
Drifting
Joined: Dec 2007
Posts: 1,309
Likes: 24
From: Coastal Georgia
C2 of the Year Finalist - Modified 2020
OK, thanks for all the responses. I'll try shimming the rear to close up the gap at the top a bit, and then fiddle with the hinge adjustments some more to see if its going to work or not. If not, I'll probably have to take it to a shop to get the work done...
Thread Starter
Drifting
Joined: Dec 2007
Posts: 1,309
Likes: 24
From: Coastal Georgia
C2 of the Year Finalist - Modified 2020
Just an update to this thread...I went back and measured again, and the gap at the top of the rear edge was significantly larger than at the bottom. I shimmed the #5 mount, did some readjusting at the hinges (a couple hours worth, actually) and I now have the gaps at 1/4" all the way around front and rear.
Now its onto the driver's side.
Now its onto the driver's side.
Thread Starter
Drifting
Joined: Dec 2007
Posts: 1,309
Likes: 24
From: Coastal Georgia
C2 of the Year Finalist - Modified 2020
It did, it actually looks pretty good now. I still need to install and adust the door striker to see if there are going to be any issues...
Race Director
Joined: Jan 2003
Posts: 17,638
Likes: 3,651
From: Central Arkansas
A panel gap of 1/4 inch on a painted body is a little more than desired but if you can center the door in the opening so that the gap is even front and rear I think it will look fine and not be too noticeable. Cars of the 60s didn't exactly have Toyota-like 1/8 inch panel gaps all the way around. And I suspect that not all Corvettes rolled out the assembly plant doors with gaps meeting the AIM specs.
