Box covering coolant tubes has been cut

[karhawk]

Some brilliant SOB figured the best way to change the coolant tubes under the car was to cut off the top of the box covering the tubes all the way off with a saw zall. How important to the chassis of the car is this piece?
It looks like a pretty straight forward wielding job to do once you get a lid fabricated. Is there anything a person should change about the design since I guess I have to fabricate something.

 

[spiderrey]

You can always strip it off another car. My car was butchered when the p o replaced the tubes. I stripped the cover off a parts car, it will go on my car some day.

 

[bb4re]

This was just asked yesterday...

...by a newbie. I have checked with two extremely knowlegeable and experienced X folk, and they both independently agree that there is no structural worries with the loss of this metal.

 

[TonyK]

I dissagree

See my post

http://xwebforums.com/forum/index.php?threads/2957/

Any section of a car that has spot welds 2" apart and 100 of them adds to the stiffeness of the car body. Some of these spot welds were in very diffiucult portions of the tube box flange. Meaning they didn't have to go to the bother of placing the weld if it wasn't needed.

TonyK.

Grimsby Ontario Canada.

 

[Rupunzell]

+1

That "cover" is structural. Notice the bends have a large radii with no sharp corners and is fastened to the body by a lot of spot welds. If this was a simple non-structural cover, Bertone would not have built the chassis this way nor, did Puelo and the other engineers involved design the chassis this way. No engineer would put that many spot welds or design a part with such a large bend radii or sheet thickness for a simple cover.

Here is another discussion about the "cover":
http://xwebforums.com/forum/index.php?threads/8513/

The chassis will function without the mid-tunnel cover, but it will reduce the rigidity of the chassis. By how much, without some testing or modeling, I don't have the numbers.

It's worth noting that an X has greater chassis rigidity than a Porsche 911T from this era. Try jacking up one corner of a X (in good condition) and open the doors, try this on a 911T and one will discover the doors don't open well. This is true for a host of open top cars. That Mid-tunnel bottom cover is one of those under-appreciated structural items designed into the X.

Bernice

See my post

http://xwebforums.com/forum/index.php?threads/2957/

Any section of a car that has spot welds 2" apart and 100 of them adds to the stiffeness of the car body. Some of these spot welds were in very diffiucult portions of the tube box flange. Meaning they didn't have to go to the bother of placing the weld if it wasn't needed.

TonyK.

Grimsby Ontario Canada.

 

[EricH]

"Does something" versus "necessary"

The chassis will function without the mid-tunnel cover, but it will reduce the rigidity of the chassis. By how much, without some testing or modeling, I don't have the numbers.

Some random data points:
1) One of my X's had that cover cut off by a PO. I've been driving it that way for a while without any problems, it doesn't feel any looser than the others.
2) Another of my X's has the cover, but also has a rectangular hole cut in the top of the tunnel, just aft of the opening for the shift lever... the work of a PO's mechanic, apparently trying to get more access to the tunnel. There are cracks radiating from the sharp corners of the rectangular cutout. I drilled the tip of the cracks, don't know if that stopped them from propagating further.

#1 tells me that you CAN live without the cover and nothing awful will happen. #2 tells me that we're dealing with a high-stress area, and that cover has to add to the margin of strength, even if it's not necessary.

I am very happy that car #2 still has its cover; the cracks tell me that it needs all the strength it can get. Yes, I know that I should be welding up a proper patch for it.

 

[karhawk]

Good information all Thanks

I am still trying to fine tune my search results.
I am in favor of replacing the top of my cover, PO left the walls intact just the top was cut off. It would seem to be a simple fix, I will have the local mechanical sheetmetal shop fabricate a top with approx. 1" sides out of appropriate thickness non galvanized steel and have my muffler guy mig weld the cover on. The open ends I will fill with spray foam to keep out air and moisture. Now would be a good time to change the heater tube as some have mentioned. The whole job should cost approx. $200
Hey TonyK where would we be without people like you? Nice photos of your repair!

 

[Black-Tooth]

Well Chris... I dunno how much...

... you seem to value my "opinion"... But I too vote for the NO "NECESSARY" STRUCTURAL VALUE side...

If you go to saw or cut one of the cars in half you will find THREE layers of steel in that area... and our Fiat engineers, although wonderful in some arenas, were severly lacking in others.

There can be NO argument that the cover will AID in increasing the structural integrity... but whether it is NECESSARY or not should be the REAL concern.

Secondly... I admire Tony K's work and respect Bernice's opinions... but the SIMPLE fact is... that cutting off the pipe's bent ends and running 1 1/4" copper pipe through them and either sweating on fittings for angles or using longer flex hoses is a simple and quick and effective fix... and might I add INEXPENSIVE! It will last longer that most of us have time left on this earth also.

It DOESN'T require compromising the "structural integrity" of the car either!

You have your choices... I believe there is still a few different pictorials in the Best Of section.

Good luck with your decision...

 

[karhawk]

The pipes were already replaced on my X, the bottom of the box was not, I will have a lid fabricated out of proper thickness steel and have it welded on since it obviously WAS a structural piece designed for chassis rigidity.