Chev 4's are pretty noisy and transmit engine noise and vibration through the car, as the engine is bolted directly to the chassis, metal to metal.
The idea was to insulate the motor and transmission on rubber mountings, hard rubber, but rubber never the less. At this time I was working at a furniture company in Bayswater, and had after hours access to not only the workshop, but also overhead cranes, forklifts and other great toys for boys to play with. So it was a Sunday afternoon, and I had done the preliminary stripping of engine bay components in my garage at home. Why there and not in the factory, I can't answer, but then I had to ask my wife to tow the car from The Basin to Bayswater. The car was safely stowed away in the factory and after work the next night I pulled out the engine and trans with the overhead crane. Every workshop should have one.
The process consisted of three stages:
1. Reduced the front engine mount the thickness of a sandwich mount, approx 7/8 inch. That was pretty easy, cut and welded the reduced original mount, fitted the rubber mount and bolted the whole thing back together.
2. The transmission mounts on the cross member were also pretty simple. I threw away the metal spacers that fit between the cross member and the chassis mount, and replaced with approx 1/4 inch hard rubber, which I had drilled holes in to match the chassis mount. I then replaced the bolts with longer ones and fitted a 1/4 rubber pad to go under the bolt head and in between the chassis mount. On the transmission side, I fitted another 1/4 rubber pad to go under the nut and in between the cross member bracket.
Once bolted up the assembly consisted of the following:
* Bolt head
* Large washer
* Rubber pad 1/4 thick
* Chassis mount
* 3/16 rubber pad
* Transmission cross member
* 1/4 rubber pad
* Large washer
* Nut
They key was to compress the rubber pads and inserts to half thickness, which eliminated any chance of engine rock. To achieve this I used very hard rubber to start off with.
3. This is the tricky bit. I used something like a 1 inch round rubber mount, threaded bolt on both sides. Cutting a piece out the top of the cross member, approx 1 inch on each side of the hole where the engine originally sat. I then fitted the engine in place, securing the front and transmission mounts. With the rear engine mounts fitted, but hanging in space, I established the position where the lowered mounting point would be welded onto the cross member. I located the contact point 1/8 inch lower than required, as its easier to pack it up as opposed to being welded in too high. I then removed the engine and welded in the lowered mounting point into place.
The end result was reduced engine noise and vibration. There was and still is no sign of any engine rock or movement, and I tested to ensure there was no forward movement of the engine under heavy braking.
These two photos shows the original type front engine mount, and the sandwich mount that was adapted.The front engine mount was cut reduced by the thickness of the sandwich mount, and re- welded.
Now 25 years later this improvement is taken for granted, but I am glad it was done, even though it was a lot of work at the time.
After 1985 no further improvements (apart from repairs and or breakdowns) would be done on the car until 2009.
Foot note (1st May 2011)
I was prompted by this posting to check the engine mounts, which have remained undisturbed since 1985.
The engine mounts were installed 1984, and during the writing of this blog I decided to check their condition.
Originally thinking it was going to be a minor tidy up, it soon became a big job, taking 2 days and after removing the bonnet and radiator consisted of the following:
Front Engine Mount
I noticed this was a bit softer than it should be. Probably from being continually coated in oil for 26 years. Not a bad run all the same. When I removed the mount it was completely shot. I reinstalled the original full steel engine mount on the front of the engine, and later supplemented this with a 4 mm strip of neoprene rubber between the mount and the chassis, as engine noise increased with the metal to metal contact. After this the car was a lot smoother. As smooth as a 1928 Chev can be that is.
My conclusion is that the front mount had been soft for several years.
Rear Engine Mounts
These are still in good condition, but I will replace them next time the engine or transmission is removed. All I did to these mounts was to insert a 2 mm washer to level off the engine and to match the thickness of the rubber pad under the front mount.
Transmission Mount
The 2 bolts on either side required tightening and I then discovered the rubber pads had been compressed to where they were no longer effective.
The only solution was to replace them, which I did over 2 days. This time I used neoprene 6 mm rubber instead of Goodyear Tyre side wall for the outer pads, and 4mm neoprene rubber instead of 2 mm rubber sheet for the inner pad.
The end result is a smoother engine during acceleration, cruising, and most noticeably when backing off.
Let's hope I get another 20 odd years out of these mountings.
The only other comment of note is how times and things change, and how with modern tools at your disposal, jobs are so much easier. If only in the seventies my garage had contained the following:
Pedestal drill
Variable speed power drill
Bench grinder
Angle grinder
Dremmel
Bench press
Sand blast cabinet
Punches
Nut splitters
Cutting disks
Grinding disks
High speed wire brushes
Butane torch
Etc
Etc
Etc.
Progress is a wonderful thing, tool wise anyway.
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