Thoughts on Restoring a Morgan
Putting the Chassis Back Together

©By: John T. Blair (WA4OHZ)
dot_clear 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.
Boy time flies when your having fun dot_clear
It is currently November 12, 1990 and I have been at this weekend project (HA HA! - I told my wife that this would not take very long) for about 1 1/2 years and have at least 4 months of work remaining (Note: It turned out to be another 2 years). Things have not been done exactly in the order as I've been describing. One weekend I plan to work on some part "A" but due to weather (either bad or extremely good), lack of manpower (I need a second head or another pair of hands - usually my father's), I end up working on some other part "B". (Hey guys - notice those variables! - who said you wouldn't use that algebra?) I had hoped to have the chassis finished, off the crutches and on its feet by last December (1989). The chassis was ready for reassembly last October, but I kept putting it off working on other things.

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.
Aligning the Front Subframe to the Chassis dot_clear
The new chassis was not drilled, with the exception of the brake/clutch pedals and the rear springs. Consequently, all the holes for attaching the firewall, wood subframe, rear shock absorbers, front inner fender walls, and the front end subframe must be drilled. The first item I tackled was reattaching the front end subframe. It had to be aligned in both the vertical and horizontal planes with respect to the chassis. My dad and I spent an hour or so trying to figure out how to accomplish the job. We finally came up with the following procedure. (Note: Since the front end was not replaced, its mounting holes were used as the template for drilling the chassis.)

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.

align ft sub frame

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 bracket.
The rear shocks dot_clear
The next items to be attached to the chassis were the rear shock absorber mounting plates. To determine where to mount them, I took the right side mounting plate and bolted them on the original chassis. The distance from the crosswise stringer (which forms the back rail for the seat pans) to the front edge of the mounting plate was measured. Using a combination square, I measured the distance from the top of the mounting plate down to the top rail of the chassis. I even measured the angle the plate made with the top rail of the chassis (90 degrees - a right angle). Now the mounting plate was unbolted and set on the new chassis. The mounting plate was moved forward and aft until the leading edge was the correct distance from the stringer. Then it was loosely clamped to the new chassis. The height was measured, adjusted, and the clamp was tightened. Finally the angle it made with the chassis top rail was measured. After the initial positioning was complete, all measurements were checked. Once all the measurements were correct, the drilling points were marked with a transfer punch and the holes were drilled. The same process was used to locate the left side shock mounting plate.
The rear leaf springs dot_clear
Before the rear springs and rear end can be installed, the gas tank bed must be bolted to the chassis. One word of caution here: the gas tank bed can not be more than 3/4 inch thick at the left and right sides. If it is, the springs will not fit.

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.
Positioning the Motor mounts dot_clear
Now that the rear suspension is in the car, the engine and transmission mounting brackets can be positioned. The drive shaft must be bolted to the rear end. The engine and transmission must be bolted together (the clutch does not have to be in place). The rubber engine/transmission mounts and the mounting brackets are bolted to the engine and transmission. With the engine and transmission bolted together, pick up the unit with an engine hoist. As the engine/transmission are lowered into the chassis, slide the drive shaft onto the rear shaft of the transmission. Slowly work the engine rearward until the yoke on the driveshaft bottoms out. Then slide it forward between 1/2 and 3/4 of an inch. I marked this location by placing a piece of masking tape on the transmission tail shaft casing. (I placed a thin piece of cardboard on each side of the chassis by the engine mounts to keep from scratching the chassis. Then the engine was carefully lowered into the chassis until the mounting brackets seated. Again, the drilling locations were marked using the transfer punch. The engine was removed, and the holes were drilled. The engine was reset in the chassis and the alignment of the mounting brackets was checked. The engine was removed and set aside.

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.

dot_clear Enjoy your Morgan.

dot_clear John

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