Bonnet Alignment

Subject:[E-Type] bonnet fitting (very long)
Date:Sat, 15 Aug 1998 10:02:08 -0500
From: Steve Kemp

I must say that a couple of days away from this list can destroy my ability to get anything done for an hour or so. Case in point is the other night, where I looked at the volume of mail in the inbox, ascertained that my car needed more attention than you guys, and quickly shut off the computer. As a consequence, it sometimes takes me a while to reply these days.

Someone had asked if the conversation Paul Bjarnason and I had over the rebuilding of a bonnet could be made public. Paul, hopefully you don't object, but here goes...

Basically, Paul has the luxury of getting to reassemble a bonnet made up of wings, a center section and brackets that have never met each other. Needless to say, the hope of them fitting right the first time is probably nil. To first order of day is to establish a starting point. So, my advice was to first make sure the car was on all four wheels with preferably all of the weight in it. These cars can sag a little, and aligning the bonnet with all the weight in (engine and trans) is preferred to get the correct fit the first time out. If you don't, you may have to remove or add shims after you're all done to dial it in and there may not be enough adjustment to get it back to perfect. Assuming the weight is in or minimally the car is on all fours, you want to mount it for a trial fit. You will want to start with a lot of shims pushing the bonnet forward and some shims (perhaps a 1/2") lifting the bonnet up at the front. I would also put the balance bars in (the springs) so the bonnet is exactly how it will be when finished.

Check the back edge of the center section for squareness and clearance. I prefer about 3/16" of an inch because the bonnet will move backward upon hitting bumps and chip the paint to give it that factory look if you're too close. If you're lucky, removing or adding shims will square it up and your done. You may find that getting down to zero shims doesn't get you close enough or when you get down too far, the mudshields interfere and the bonnet catches won't align. If you do, push the bonnet forward with shims so that the brackets can be aligned properly and the mudshields clear.

Now check the gap between the sills and the bottom of the wings. For the purposes of this exercise, you may want to temporarily remove the balance springs. The gap should be nice and even. If it isn't, use shims to raise or lower it at the front. You don't want to add so many shims that the bonnet won't naturally rest on the rear seal (but you can only check this with the balance springs out). If the bonnet rests well on the seal and the bottom of the wings hit the sill, you have two options. First is spoon down the sill and do some finishing body work if the problem is minor. If the problem is major, you can slit the wing horizontally and restitch it or cut the top of the sill and repair it. Both of these are only scary propositions when first contemplated, but not killer projects for the experienced body man (or body woman, if there is such a thing). I personally would opt for professional help who had done this before if I needed it, simply because they could probably do better than I with no previous practice and much quicker.

In Paul's case, as in mine on a previous car, there wasn't enough metal to fill in the gap between the back edge of the bonnet and the bulkhead. I cautioned Paul, as I do you, not to subtract so many shims as to move this back to tighten it up while causing your catches not to align or the mudshields to interfere. As a consequence, 19 gauge metal has to be welded along the back edge of the wings and center section. On my current car, I had to do this for about a foot on one wing only. Someone with an experienced mig can do this in no time flat. You will probably want to add a little more metal than needed, as you can then grind/file it back to perfect squareness and clearance. You will also want to weld it on both sides and cover the ground down seem with lead. My factory fit had so many divets that I wound up moving the whole bonnet back and taking off some metal. Now, that said, I did change the hole size on my bonnet catches and monkey around with the mudshields because I wanted to move it back so far. I made this trade-off over welding new metal to the back of the bonnet in this instance.

As I told Paul, my preference is to chemically strip (redi strip or other) the bonnet and all of its pieces before bolting it together for the fitting process. Before sending it to the stripper, I would wire all any of the brackets that appear like they are spot welded to the bonnet together with the bonnet. This keeps them from falling into the unretrievable reaches of the stripping tank and getting lost. In my case, the brackets are welded to the bonnet (early car), and the reassembly process was a breeze. In most of your cases, you get to do what I did on a previous car and glue the brackets on. Most body people will tell you that adhesive and seam sealant should be applied to bare metal, then primed. Something rubs me wrong about the concept of leaving bare metal, so I acid primed all the pieces. and start the reassembly process. As it stands, the painter bitched about the sealant on top of the etching primer, but I noticed he got over it and the job came out fine just the same. He just had to put a sealer on these spots before painting though. To simplify the assembly process, you may want to mount the underpan, then the center section, then the wings all on the car. For kicks, you could take for a ride around the block with the center section and no wings. It's good for a laugh.

Once the gaps have all been taken care of, those with brackets will need to either glue them in now or as part of the fitting process. Measure the distance between the upper corner of each sill that meets the wheel arch. Next tie a tourniquet around the wings and bonnet at that same point on the bonnet. You want to pull the wings in where they will meet the sill at the wheel arch about 1/4". Now glue the brackets using Sikaflex (think that's its name) or whatever your preference is. If you do not do this, you may find that your wings flare out once the bonnet has set and don't line up nicely with the sills when finished. If you find that they are tucked in too much, you should be able to bend them out enough to align them.

At the rear of the bonnet, you will minimally need to adjust the bracket that joins the wings with the center section to pull the wing in or out. Worse case is usually having to oblong the holes on the bracket to gain more movement or grinding it a bit to get the screws to line up.

When you're all done with this process, your bonnet should fit PERFECTLY. It should fit perfectly without the balance springs in, coming to rest squarely with the bulkhead and not sticking up or out anywhere. Once you attache the balance springs, it should simply be a matter of closing it until the safety catch grabs and pulling it down the rest of the way by using the catches. Ideally, you won't have to push it down to get the catch to grab, but this often not the case. On mine, the right side needs to be closed before the left in sequence. but that's close enough for me. YOU SHOULD NOT HAVE TO PUSH THE WINGS INWARD TO GET THE PIN TO GO IN THE RECEIVER. If you do, something isn't lined up right, and you need to start from the top again.

Good luck to Paul and all of you who get to live this experience.

62 OTS

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Rev Aug 18, 1998 GWC