VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1929-1932 '31 Double Bar Bumper straightening

At some point in its 80+ years, the front bumper for my '31 Coach has been "bent outa shape". Ive been able to take the little kinks out of the 2 outer bars (using a vise) but there remains an issue with the support bar, which is much heavier duty (spring?) steel I suspect. When mounted on the car, the back bar sits about 4.25" from one tire and 5.5" from the other, indicating the outer part(s) of the back bar are bent. Not much noticeable in way of kinks etc, so I am planning on trying to get it reset so both sides are same.

When I place the back bar on the work bench sitting on its 2 mounting plates, one plate has a slope upwards of about 1/8" whitch matches the slope on the face of frame horn. The other plate slopes upward 3/16" or more, suggesting this side needs to be flattened somewhat (that is the end furthest from the tire)
Does anyone have a good one who can measure distance from tire to back of bar so I know what to aim for? While common sense would suggest one side may have been pushed in an accident, it is also possible one side was pulled out a bit during a towing exercise! So I may have a combination of 2 things. The center part of the bar seems perfectly symettrical.
A second question, when final bumper is correct, is there a slight curve along the length of the double bars?

While we are on this subject, did the eyes in the support bar have bushings? I notice they are about 9/16"+ dia while bumper bar eyes are about 1/2" dia.

Hello Gunsmoke,
My double bar front bumper is in pretty good shape considering it's age. I cannot speak to the end bolt eye diameters because they are not taken apart. First off, my frame horn mounts appear straight up and down/vertical, no angles. The sliding mount pads on the black support bar are vertical. The black support bar and double chrome bars are vertical, all when mounted tight. Could it be that the Coach was jacked up by the front bumper and bent? The aft face of support bar to tire tread is approx. 5 inches both sides, (stock wire wheels and tires). Looking at the installation, I believe whatever happens to the support bar, the double chrome bars follow along, bend back one side, the other side moves forward. Here is what I see of the support bar: (All measurements are from aft face of support bar). From center double bar mount, the support bar gently arcs rearward 5+1/4 inches to a point 10+1/2 inches each side of center mount. From there the support bar is straight to the end eye bolts, no bends. The distance between eye bolt centers is approx 59+1/4 inches. As for the double chrome bar curvature: mine stays straight for 20 inches each side of center mount, then arcs rearward approx. 4 inches. If you can draw and make a template you might see where the issues are with your assembly. Good Luck

You have been very helpful Harry. When I mentioned "slope" of frame horns, with the bumper off I placed a straight edge across both horns, and the horns have a slight inward pitch toward center of car, not a big issue, I initially thought they would be dead flat across, but indeed they have about 3/32" of lateral pitch.

Both of the end pieces of my back bar are bent/curved. One has about 5/16" of bend (mainly at one spot near center) while the other has a more gradual curve of about 9/16". You indicate your end sections are straight? I think what I will aim for is to simply get both ends about the same, perhap with a bit of a curve, so they fit about 4.75"-5.0" from tires. As long as I get them about equidistant from tires/fenders, they will look fine.

Can you tell me the distance center to center for the smaller medallions from the center medallion for both the front and back bumpers. Mine appear to have been moved more than once! I'm guessing about 15" for front, 16" for back.

Hello Gunsmoke,
The slope you measure on the face of the frame mount horns might act as a twist/lockdown between the sliding mount pads and support bar to keep everything tight and centered when the bolts are tightened up. Yes, the outer 19+1/8 inches of each end of my support bar are straight, no bends. If the bar to tire tread distance were off by 1/2 inch between sides, I'd think it would be hard to notice, unless it was a hard core inspection from the club. I'll have to get back to you on the medallions measurements for the front bars. I don't think I can help you with the rear bumper, I have the split rear bumpers with the spare tire in between in the middle. If I recall correctly, you run sidemounts so that gives you the full length rear bumper. Someone should be able to help with the rear bumper medallion measurements.

Hello Gunsmoke,
My front double bar bumper medallions measure 15+1/2 inches each side from the center of the center mount medallion. It looks pretty centrally located between the center mount and the outer ends.

Thanks again Harry, only a few of us '31 Coach restorers around eh!