Rookie needs guidance for compression test

gdizzle said

OK, just got a compression tester from Oreillys loaner program (free) for 2 days.
I watched some YouTube and read a couple posts here.
My main questions,

1: Do I have to remove the valve cover?

No.

2: Do I have to remove the sparkplug tubes?

What type of tester do you have, screw in type? I don't think you do.

3: Do I have to disconnect the coil?

Yes


4: How tight does the compression hose need to be in the plug hole?

If it's the one that's pointy rubber, just enough pressure so it doesn't leak out. See question above.

5:Now if I am able to do that part, what kind of compression # should I be looking for?

Not sure on a /6.

Now I also see Wet vs Dry. Since this is Slant 6, how is it possible to coat the entire head of the piston with oil? And once the oil is in there, will it just burn out when I reconnect the plugs? Is that safe?

thanks in advance
66 dart 225 slant 270 3.7

Click to expand...

First and foremost, I would make sure the valves are adjusted up properly before you start.

I would run the engine and let it warm up, let it cool to the point you can work on it.

Remove all of the plugs, pull all of the wires (keep track of which one goes where), unplug the coil wire, use a screwdriver to hold the carb open.

Start with one cylinder and just go from front to back in order WRITE down your numbers. You have just done a dry test.

To do the wet test, a squirt of oil in the cylinder and repeat the process, WRITE down the numbers.

You will want to let the engine turn over about three times for each test on each cylinder, WRITE DOWN the highest reading.

Put a battery charger on the battery so you have even cranking throughout the process.