1996 e250 Rear Door Sheetmetal Cracking (due to Spare Tire Mount)

[MarcDuchesneau]

Hello everyone,

I have an oldie but a goodie 1996 Ford E250 Sportsmobile.

Please see attached photo.

I noticed recently the rear van door sheetmetal is cracking where the spare tire mount is attached. The metal just seems to be fatigued after all the years. There's a small metal plate on the inside of the door where the bolts attach to.

Any ideas on how to rectify? I don't care if it looks great or not, mostly I just don't want it to get worse. I was thinking of installing a larger steel plate on the inside to distribute the weight beyond where it is cracking. Then maybe some bondo to cover the crack. Would this work or make it worse?

Any insight is greatly appreciated.

Thanks.
Marc

 

[posplayr]

Given the questions, I would suggest you start with a fresh door. If I were doing it I would be trying to visualize how to spread the load on the door skin out sufficiently do that the point loads at the exterior bolts dont exceed the local sheer stresses of the skin. of course a damaged door has dramatically reduced strength and that strength needs to be reconstituted if not increased just to start. This is why starting with a new door would short cut step #1.
Since the existing damage can’t be assessed from the picture, im going to assume it is fixed or replaced.

From what has happened it is clear the thickness of the metal used as backing was to thick and too small. If it were thinner it would not have put as much stress into the skin and if it was larger the stress would have been spread more.

It might be that you need layered backing plates. Each successively larger than the first. Based on experience my approach would be to spread out the forces as much as practical. The objective is to avoid having to do it again.

‘M not precluding doing various plug/spot welds to bind the layers together towards the middle but allow them to flex near the edges to reduce the stresses in the skin. You can kind of think of a sort of wide leaf spring with each successive layer making the structor stronger/ stiffer

By the time you are done, the original cravks can be welded down/ground down and bondoed down.

 

[MarcDuchesneau]

Thank you. I think I'm reading in between the lines to take it to a body shop!

 

[posplayr]

Thank you. I think I'm reading in between the lines to take it to a body shop!

It could be a body shop but more importantly something like a fab dhop that understand how to support sheet metal loads.

If NASA were to solve the problem they would develop a 3d simulations of the skin and the sheer stress profiles and then go through successive additions to spread the load out sufficiently to avoid fatiguing the outer body.

Alternative approaches might be to mount at the hinges and avoid putting big loads into the skin. It might also be possible to support mounts trrogh an internsl structure that ties to hardpoints (eg hinges door latches).

An experienced fabricator would do some of these calculations in their head ( not literally but subjectively) and improve the solution within the constrains they have.

A new door would avoid having to fix anything snd buying s reliable after market tire mount would avoid much of the door damage.

One easy thing I have planned is having a rear tire mount that rests on the bumper relieving a lot of stress on the door mounted tire carrier.

Reading between the lines, the original mount is substandard and has fatigued the door skin. An new mounting system or s stronger door skin is recommended or just do some minor mods to reduce the stresses for some additional longevity (eg round the edges of the backing plate and abs plastic cushions between the backing plate and the skin)

 

[MarcDuchesneau]

There are of course better ways to attach the spare tire (hinges, bumper, etc) but I can say that it lasted nearly 30 years so I can't complain.

 

[86Scotty]

Salvage yard door. Super easy to find especially since your van is white.
$150?

Bigger washers.
.50?

Half day of work with a friend, at most.
6 pack of beer.

:b5:

 

[arctictraveller]

I would get the cracks spotwelded together, fabricate a much larger backing plate, touch up the paint, and reinstall.

 

[86Scotty]

I would get the cracks spotwelded together, fabricate a much larger backing plate, touch up the paint, and reinstall.

Last time I fixed this issue I put about a 1' long piece of angle steel vertically inside the door right up against that bend, if I remember right.

 

[batgirls]

I have the same issue (plus i think someone backed the spare into something at some point).

I picked up a good as new door at my local junkyard for $70.

I hope to get an aluminess or similar bumper with a spare tire mount. At that point I’ll install the door.

It and it’s passenger side mate will need to be repainted so they match. Stock ford white doesn’t seem to be the same as sportsmobile white.

Good luck

 

[posplayr]

Last time I fixed this issue I put about a 1' long piece of angle steel vertically inside the door right up against that bend, if I remember right.

Pinning a piece of 1/8" angle iron pinned/riveted/bolted to the inside of the door (the part perpendicular to the outside skin) will do best to support the outer skin.

With a fresh door, this would be the least work for what will probably last quiet a while.