I though I'd use my new digital camera documenting my experiment of revive the Toyota Tercel from the last engine failure.

First I had to figure out what failed in the engine. I removed the spark plug from the suspect cylinder and started the engine. I looked through the spark plug hole and sure enough I could see the top of the piston wasn't moving at all. The piston rod must have broken off the crank shaft. I took the car for a ride but what was happening was the piston would slowly go down the cylinder and make contact with the rotating crank. This was not good. Somehow I though if I could keep the piston from sliding down the car would be drivable.

The only way to keep the piston up was to use a vacuum. The problem was that as the engine rotated the valves would open up and would release the vacuum. I had to stop the valves from opening.

Off came the valve cover, I loosed the valve lash adjustment screw and with a little force [read: a lot of force and use of hammer] I removed all three rockers under the cam shaft from that piston [yes the Toyota has three valves per cylinder, two intake, one exhaust].

I put the valve cover back on and started the engine. It ran fine until the piston made it's way back down and started making contact with the crank again. I now needed to create a vacuum from the spark plug to suck the piston up. What could I use?.....Why not use the vacuum the engine makes as it sucks in the air mixture from the working pistons? This vacuum is actually used in the power brakes unit. I figured I could tap off this and somehow feed it into the defective cylinder, but how? It would have to be a tight fit that could not leak.

I decided I would take the spark plug from the dead cylinder and machine a hole down the center. I took the spark plug to my trusty lathe, and began the process.


 

It wasn't easy, but the job was done. Here is the modified spark plug with a hole down the center.
 

Here you can see the hole right through the spark plug.

I now needed some  hose to connect to the spark plug. I took some fuel line hose that I had lying around for my fuel injection project.
The hose was inserted and clamped on tight.

The spark plug with the hose was then screwed back into the engine.


 

I disconneted the hose that goes to the brake boost (power brakes unit) and connected it to my spark plug hose.

I started the engine, let it run for a few seconds and then stoped it. I removed the spark plug with the hose and look inside. Sure enough the vacuum had sucked the piston all the way up. Looks like it worked. I put the spark plug back in and took her for a test drive. The first problem I noticed was I had no power brakes. Boy did I need a lot of force on the brake pedal to stop the car. I drove her hard for a while. No noise whatsoever. Looks like the problem was fixed. I however needed to get my power brakes back because this was dangerous.

I found a TEE connector in my basement and reconnected the hose back to the vacuum source.

Took her for a drive again. Power brakes were back and engine ran well. I increase the idle rpm since the engine was running a little rough with only 3 out of 4 cylinders working.

The toyota lives once again.......