Bumper installation 4.2 S1 OTS

I am trying to fit my bumpers before my early '65 4.2 S1 gets painted to see if any body work is needed to get them to fit nicely. Does anybody have a good detail photo or drawing showing the hardware assembly? If not:

  1. What sets the distance of the bumper to the car body?
  2. Do the aluminum spacers (BD20893) on the rear bumpers go as shown in the photo below? These don’t seem to be thick enough to reference on the body. Does the chamfer go towards the body?

image
3. Where do the square spacers (BD20663) go on the front bumper?
4. Approximately how much gap should there be between the bumper and body?

thanks,
Dave Christensen

You are smart to do this now.
I find the part numbered shims sold are aspirational in nature. I almost always have to supplement them with a collection of washers or even custom made shims. The front bumper is the worst because of the taper of the nose piece. I tend to start with the OEM tapered shim there but frankly, I have had to resort to a wood block that I can grind quickly to suit to get the bumpers level and then use that as the basis for grinding the stock piece, or even making one from scratch.

I think a 1/4" to 5/16" gap will get you in the ball park. Have your “gap rubber seal” on hand so you can test fit it.

Fortunately or unfortunately, significant bodywork to make the bumpers fit is really not possible. Grinding the bumper blades is probably your best bet.

Have your front running/parking light assemblies on hand and ready to test fit. Do not be shocked if they intrude on where the bumper blade should go. In that one case, I did body work body openings and the captive nuts, in order to raise the light assemblies about 3/8" to allow the bumper to be level. That of course does represent body work you want to do now. Don’t forget to add the overriders and motif bar to your effort now. It is all a package and one can affect the other. As an aside, have you test fit your headlight chromes? The gap between them and the running lights may surprise you as not being the same on both sides. And your rear tailights? And door handles? And your chrome drip rails? And your mirrors? And identified and cleared the holes in your rear decklid for the logos. There is a list of things to check fit now, before paint, rather than later.

Level front bumpers and motif bar is one of my first “tells” of a good restoration. It will take time to get it right so be patient.

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David- a picture of all my bags of hardware for the bumpers and overriders. The point being there can be a lot of fiddly bits to get them installed nicely.

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Harvey thanks. I have all my original re-chromed parts and made a first pass with the body shop on fitting everything. I just ordered all the rubber gaskets and am still not quite sure how it all goes together. I have only one of the aluminum spacers and started making the rest. If the factory size is not necessarily right I will wait and cut them off as required during the next trial fitting.

Does the chamfer on the aluminum spacer go into the sort of pointy oval openings in the body to help leveling the bumpers?

thanks again,
Dave C

Regarding a chamfer, I don’t have a strong opinion on that. I tend to use flat washers to give the connections more stability. Also, especially on the fronts, I tend to fabricate some sort of reinforcement to the stock captive nuts. After so many years of abuse, sometimes the existing captive nuts are in pretty bad shape. There are many creative ways you can fix them but personally I just get some 3/8" plate stock, tap a hole, cut it out like 2x2", and selectively tack weld it to the sheet metal on the inside. This also gives you a chance to adjust their location.

My hot tip on gaskets is to buy the very nice reprint of the SPC from JCNA. The drawings in it usually have a detailed inset showing the configuration and orientation of the gaskets.

Help, I’m not familiar with that abbreviation.

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Spare Parts Catalogue

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I spent about 2 to 4 hours on each bumper blade on Tweety.

Harvey, is this the SPC you mentioned? Mine is lacking in what I would call detail drawings. While ALL the part numbers and quantities are listed, many items such as fasteners are not shown in the drawings. I have an original copy of the 3.8 catalogue and this 4.2 reprint. If there is something else/better I will buy it.

Your picture shows conical round s9acers on both bolts. That would be incorrect. The front one next to the motif bar takes the square wedge shaped spacer. This is what helps correct for the slant of the bonnet nose. Most droopy blades you’ve seen are missing this. But as Harvey says it only gets you in the neighborhood of correct. One of mine required about 3 extra SS fender washers, cut in half and glued together to provide extra lift.

The conical side of the other one, faces the car. It kind of fills the hole. in the bonnet and mates up with the fender washer you’ll be placing inside.

I shot for less gap than Harvey, maybe 3/16 IIRC. I wanted the seal to prop up against the body at about 30 degrees. You’re going to have to grind the edge of the blade to get it even. You might have to extend the center holes downward to get them parallel to the ground because you are limited by how high you can make the outer end. When you’re getting close, test fit everything including the side lights with their seals.

“You’re going to have to grind the edge of the blade to get it even.”
Is this only for replacement bumpers? I replated the originals and hope that I don’t have to grind on them.

Unfortunately no, my originals required a far amount of grinding on both ends. Otherwise the gap is huge in the center, and the seal stands vertical at the ends. People have had reasonable success using a high speed grinder, rotating in line with the edge (so it won’t try to flake away the plating) and then paint the edge with something like epoxy paint. Maybe you’ll get lucky though and it won’t need it.

Hi David, I have a fully restored 11k mile car. What makes fitting chrome exterior trim is the lack of original factory contour. Accidents previous body work etc make fitting the chrome a challenge. Classic Jaguar who did the rolling restoration used my fittings in the Copper stage of plating to match body contours in sanded high build primer. Once all pieces where fit, the parts that needed Chrome were returned and then Nickel and Chrome were plated. Classic Jaguar then painted the car. Todays paint is significantly thicker than what was originally painted by the factory. You are right to assume some either body recontouring for the tail lights, door handles and headlamp trim rings or grinding the chrome before plating will be needed to make everything fit. As for the front bumper spacers the concavity is pointed down thereby allowing the bumpers to be level. Also depending on the body work needed you may need to use additional spacers. The available body gaskets for the parking lights and tail light is also problematic. I have a set of OTS NOS Lucas gaskets for the rear tail lamps and after comparing them to the East Coast Supplier…they aren`t even close. If you have already purchased your rubber trim parts you will see what I mean. I have used C.O. Baines in the UK for all my rubber trim. It is worth the wait, shipping costs etc. almost like NOS.

Regards, and USE RACERS TAPE IN THE SNOUT OF THE NOSE TO KEEP YOUR PAINT SAFE!!!
Allen

OK, sorry, I get tired of writing out Spare Parts Catalogue, although I do get a small thrill spelling catalogue in the English manner! I don’t keep the 4.2 SPC next to my computer, like I do the 3.8 one but if you look at the “Plate” drawings, in your case in the section Body Fittings for OTS, one of the last drawings will show the rubber moldings. Then look for the little circles that provide a detail view of the end of each molding. I can confirm that the reprint sold by JCNA is of good enough quality that you can actually see what is inside the circles. In my early days, I bought a reprint from one of the usuals and it was blurry in this regard.
OK, quick tutorial on the SPC. There are 50+ Plate drawings. Major components are shown and given number from 1 to whatever. Prior to the Plate drawings, which also have a number, is the organized list of parts. Go to the section for you plate drawing (say 50) and then look for the part number you are interested in (say 50-1). There you will get the Jaguar Part Number (P/N), description, number required, and notes. So say you are looking at the door hinge and it is 50-1. Under the description for 50-1 you will find other line items. These are all the items need to install the door hinge. So it should list 8 screws and maybe some washers. In most cases, that is everything you will need to install that hinge. These items are not shown on the plate drawing.

Now the notes are important. You may find Door Hinge listed several times, with a different P/N. In most cases, under Notes, there will be a range of Car Numbers to which that particular hinge P/N applies. Also, the list of items that goes with the hinge may change. On my 63 FHC, built on Jan 2, 1963, things were changing fast and furious I really had to pay attention to the notes.

IMHO (in my humble opinion) you absolutely cannot put one of these cars back together without the SPC. I refer to mine almost daily. Some of the drawings are remarkably accurate in small details. For instance, my sheet metal ashtray panel has a little 45 deg lip. The piece is such that the lip could go up or down. The SPC drawing clearly shows it down. Nice!

BTW, regarding @alodmd 's comment about the parking and tail light gaskets, I agree. Not sure of the solution although a nice pattern posted to the forum that we could print out full scale and transfer to butyl rubber sheet from McMaster would be a gift to the community. Also BTW, I contacted my favorite supplier in the northeast US and they said they get their rubber parts from C. O Baines when possible.

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I agree 100%.

thank, Dave C