©By: John T. Blair (WA4OHZ)
1133 Chatmoss Dr., Va. Beach, Va. 23464; (757) 495-8229
Originally written: circa 1997
Last update: June 16, 2009
In this article, I will discuss putting the chassis back
together. Those of you who have been reading my articles know that I had a
crack in the chassis and decided to replace it. Consequently, I am doing a
ground up restoration on my 1965 Morgan 4/4 Series V. So far, I have
discussed rebuilding the front suspension, rebuilding the windshield wiper
motor, and provided some general comments on how I got into this mess, the
disassembly of the car, and restoring the wooden subframe. During the
disassembly process, each part was cleaned and painted. While this made the
disassembly seem to take forever, when things started going back together,
it was faster and the parts were clean.
When the new chassis arrived from Don Shimpkins (Morgan-Fab
Industries in Georgia), it was primed and needed to be painted. I placed
it on saw horses and started examining it for splatters from the welding.
These splatters were removed by tapping them with a 1/4 inch chisel and a
hammer. Once the frame looked smooth enough, it was painted.
To determine the original (factory) vertical alignment, we remounted the subframe to the original chassis. We set a carpenter's square between the upper and lower horizontal bars on the front end. A protractor (option for a combination square) was placed on the top rail of the chassis and its blade adjusted so it laid flat along the carpenter's square. The angle the carpenter's square made with the chassis was recorded. (On my car, the angle was 90 degrees.) The front end was moved to the new chassis and held in position using a C clamp on each side of the chassis. The vertical position was set using the carpenter's square between the two tubes and the protractor on the chassis.
To set the horizontal alignment, we measured the width of the chassis at each horizontal brace and marked the middle with chalk. The upper tube of the front subframe was measured and its middle marked. Next we tied one end of a piece of string to the centerline mark on the front end and tied the other end to the centerline mark on the rear horizontal brace. One side of the carpenter's square was held to the upper tube on the front end, while the other side of the square was laid along the string. One of the C clamps was loosened and that side of the front end was moved back and forth until it (the carpenter's square) laid straight along the string. The C clamp was then retightened. We marked the chassis for drilling by placing a transfer punch in each mounting hole on the front end and tapping the punch with a hammer. Next we drilled each hole in the chassis by drilling a small centering hole then redrilling the holes to the correct size.
Once the front subframe is attached, the remaining parts for the front suspension can be installed.
It took me about 11 months to get around to reassembling the front
suspension. This time, I did a couple of things differently. First, I did
not replace the rubber bushings in the dust covers. Based on a telephone
conversation with Bob Couch of Morgan Spares, the rubber bushings are not
needed. I also noted there was a lot of pitting of the king pin under the
old bushings. Secondly, in the previous article on rebuilding the front
suspension, I suggested using two jacks. I also suggested using two long
bolts or threaded rods as an alternative. I have used the threaded rods
for both removing and replacing the front end. This works better than
the jacks. Finally, I suggest that as soon as the upper spring can be slid
into place, the king pin bolt should be inserted through the upper shock
mount and into the dust cover. The bolt will not reach the king pin yet,
but it will prevent the spring from sliding out of the upper suspension
The mounting of the bolts that hold the rear bumper mounts to the chassis must be considered. The bolt holes must be drilled, the bolts inserted, and the shackle at the rear of the spring bolted to the chassis. The rearmost bumper mount bolt fits under the shackle at the rear of the rear spring. On my car, I had to grind the head of the bolt down to allow the spring shackle to fit. After grinding the bolt head, the spring was retried. This process was repeated until the rear part of the spring could be bolted in place.
Once the bumper support bolts are in place, the rear springs can be
installed. Start by bolting the back end of the spring to the chassis.
Next, the rear end should be set in place on the chassis and attached to
the springs. The U clamps are placed over the axle housing, the bottom
plate is located under the rear axle and the nuts are tightened. (The
order here is important. If both ends of the spring are bolted in place,
there is not enough weight to allow the springs to be jacked up to the rear
end.) To bolt the front part of the spring to the chassis, the spring
must be forced down into place. To do this, I used an 8-inch C clamp. I
placed a scrap piece of 1/2 inch plywood under the chassis, in the corner
where the crosswise stringer attaches to the chassis just behind the
springs front attaching point. The lead screw of the clamp was pointing up
and is against the spring. As I cranked down on the clamp, the C clamp
would walk down the spring. To stop this, I took a scrap piece of wood and
drilled a shallow hole the size of the foot on the clamp's lead screw. The
clamp was screwed down until the front mount of the spring aligned with the
mounting holes in the chassis, and the bolt and spacer were inserted. This
process was repeated for the other rear spring.
The steering box mounting bracket must be positioned on the chassis. The bracket mounts to both the chassis and the front end subframe. Since I had not replaced my front subframe, I bolted the mounting bracket to the front subframe and marked where the chassis should be drilled. The bracket had to be removed in order to drill the holes, then reinstalled to check the alignment. The wedge that fits under the steering box had to be ground to fit this new configuration.
There are several other holes that must be drilled: the mounting for the hydraulic brake distribution block, the front and rear holes for the main hydraulic line to the rear brakes, the rear bumper mounting bracket, and the exhaust system brackets.
The holes for mounting the firewall and the wooden body frame must be drilled before touching up the scratches in the paint on the chassis. This will be the subject of my next article.
I have come across two more parts substitutions:
a) The fender welting (between the rear fenders and quarter panels) is similar to that used on the VW bug. The cost for 25-feet is about $10. Thanks to Bates Mclain of Earlyville, Va. for this information.
b) The rear flexible brake line can be replaced with a front caliper flex line from a '65 MGB for about $13.
Enjoy your Morgan.
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