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Some Assembly Required

Some Assembly Required – Compression, Fuel, and Spark

From my earliest days of working on cars, when a car wouldn’t start I always heard “You need 3 things- compression, fuel, and spark.” That was pretty good guidance in the days of distributors with points and carburators. And it still is, although it is not much help in cars with a CAN Bus and numerous microprocessors! In this installment of SAR, I am just going to point out that I have achieved this basic triumverate for the 63 E-Type FHC project, with one exception that I will get to in a moment.

Compression- this is the least likely to be your problem but all it means is that when the piston approaches “top dead center” you should see a sharp rise in the pressure in the cylinder. A basic tool is a compression tester, which is a pressure gauge with a hose that you install in place of a spark plug. You crank the engine on the starter and read the value on the gauge. A reading of 150 psi is a typical value. If you get close to zero, you’ve got serious work to do! In the case of my E-Type, the engine had been rebuilt by Dick Maury and there was little doubt of its integrity but I used a compression gauge to hand crank the engine and validate the “firing order”, which turns out to be 153624. I did this so I could be sure that the six new leads from the spark plugs were connected to the distributor cap in the correct order. I determined that the distributor rotated in a counter-clockwise direction and indeed the correct firing order was achieved. All of this was preceded by cutting and installing 6 new copper core spark plug leads. These terminate in the iconic Champion spark plug caps and are routed through a cardboard tube on the top of the engine. I haven’t verified “spark” yet, but now all the necessary pieces are in place.

How about fuel you may ask? Well, the good news is my 3 SU (Skinners Union) carburators have been returned from marque expert Joe Curto in Queens, NY wonderfully restored. This took a while but good things are worth waiting for. I wrote an article recently about Joe, which you can read under the People tab on my website. He is a fascinating guy and his crew does a wonderful job setting up and cosmetically restoring SU carburators. These were attached to the inlet manifolds that I had prepared. The use of 3 SU carburators on the E-Type has said to be overkill by Jaguar but they present a glorious sight!

Is it time to fire up the engine? Well, unfortunately not, for several reasons. One crazy reason is that you can’t install the left rear bumper if the fuel tank is installed and my left rear bumper is still with the chrome plating shop. The more important reason is that I don’t want to start the engine until I can subsequently and immediately hit the road and get some load on it, to optomise break in, especially for the rings. So I will hold off on the initial start of the engine until the car is licensed and roadworthy. Hopefully not too far in the future!

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