|Esprit S1 Engine Stabilizer|
By Kiyoshi Hamai
Chapman Report - April 1983
I thought I had harped on the Esprit engine mounts enough when I owned one but I guess I was wrong by the number of calls I keep getting about broken engine mounts on Esprits. The culprits are mostly Series 1 cars whose cornering loads are all transmitted through the four rubber engine and tranny mounts. As stout as the two engine mounts look and as lacking in rubber the tranny bushings are, all six of them, there is a triangular hunk of aluminum with two small bushings and one large one pressed into it, on each side of the tranny. It just is not ample to control the movement of the 907 engine when it is either punched or slammed into a corner. Additionally there is problem of the closeness of the left side engine mount to the exhaust manifold.
The story goes quite simply, without a heat shield to protect the fragile rubber of the left engine mount from the searing heat of the exhaust manifold and collector pipe the mount gives up within 5,000-10,000 miles. Usually the driver will note that it becomes somewhat more difficult to find first and reverse. If this state is allowed to continue the tranny mount bushes will begin to give way and the entire engine and tranny unit will slide forward and lean heavily into the body work and engine cover at the front of the engine next to the firewall. At this point it will be impossible to find first, third and/or fifth.
If allowed to deteriorate to this state the tranny bushings will have to be replaced as will the engine mounts. PUT A HEAT SHIELD ON THE LEFT ENGINE MOUNT!
The mounts will still be overly stressed but at least they will last 15,000 miles before needing replacement. The next modification is to control the engine movement. A simple run without the engine cover in place with your rearview mirror adjusted so you can see the engine will vividly illustrate the amount of engine movement the bloody thing goes through when rapidly accelerating and shifting. Lotus found their solution to this by marketing a $80 engine stabilizer kit. This kit provides a positive means by which the engine is tied directly to the chassis cross member.
This engine stabilizer is relatively easy to duplicate and build with further adjustability. I built one for my Esprit and seems to worked quite nicely. Here then is a drawing of the stabilizer I fabricated and mounted (it mounts to the left rear of the engine).