TNRabbit

It depends on the tester. I have a Craftsman (@ $50) that does both.

The leak down test uses an air hose to pressurize the cylinder.

CajunKenny

A compression tester measures how much compression/pressure is generated from a compression stroke.

A Leak Down Test measures how much compression/pressure is lost at the peak of the compression stroke.

They are two different tests, performed two different ways, using two different pieces of equipment.


It sounds like TNRabbit has a combo unit. I wish I had one to save on space in my tool box.

cmoore2468

Dang! It wasnt the EGR valve! I was pretty sure that was the culprit after watching the video, maybe the compression test this weekend will tell me something.

CajunKenny

Post up your compression numbers.

Remember...leaving the compression tester attached for 3-5 minutes is a waste of time and tells you nothing about your engine. It only verifies that your compression tester can hold pressure.

cmoore2468

I was able to get 5 cylinders done.I could not get to one of the plugs, I need a flexible elbow. Here are my results so far.

120 120
125
120 115

vasinvictor

iTrader: (3)

We're going to need that last cylinder to form any conclusion. Those numbers are low, but all uniform. They're probably low if the engine was cold when you performed compression test. If that last cylinder has similar pressure, we need to start looking elsewhere. Please post up pics of the tips of your spark plugs. Clues to the puzzle...

cmoore2468

How do I add pictures? I have a couple of my plugs.

CajunKenny

Upload to photobucket and then copy&paste the link to the photo in the Yotatech's 'Quick Reply' box. (the same place you type typical messages)

Jasper 83

Host them on photobucket.com and copy the code below the picture labeled img. Paste that in your post on yotatech and your good to go.

Definitely need to get that last compression number. That may be your dead one. That's usually how it works for me anyway haha

TNRabbit

Those numbers are REALLY low.

cmoore2468

Update..........all cylinders are good. The previous owner had the rotor cap turned up I think to gain more power. I have turned it back and have seemed to take out the idle problem. I replaced the fuel filter and added sea foam to the tank last night. It seems sluggish, I will run this sea foam through this tank and see how that does.

vasinvictor

iTrader: (3)

Sounds good. You need to get a timing light on it and set to 10-12* with the TE1 E1 pins jumpered. I'll bet that'll take care of your sluggish problem. You can probably quit buying $10 cans of seafoam now.