Compression test how to?
Thread Starter
|
Laughing Gas
Joined: Apr 2009
Posts: 903
Likes: 9
From: melbourne beach, fl
Compression test how to?
Been driving these for yeaars and finally got me a diesel,so i am anxious to do a compression test on my motor (7.3) and it is a late 80's model.What are the basics to this process.It seems as if there is a compression test kit for a diesel aFord able @ Harbor freight,so when I get one then what would be recommended for an accurate test?
Tuned
Joined: Oct 2004
Posts: 250
Likes: 6
From: new york
Its not neccessarly the pressure but more that all cylinders are at the same pressure usually around +/- 10%. If one cylinder is much lower than the others, then there is possible problem with that cyl. valves, rings, cam, rocker, pushrod, head gasket, liner etc.
Post Fiend
Joined: Nov 2004
Posts: 5,638
Likes: 1
From: Manitoba
Actually the lowest cylinder must be no lower than 75% of the highest...... Never use oil in the cylinders, the test must completed on a warm engine. Crank the engine over at least 5 pumping strokes per cylinder (ignition off). Record the highest reading and number of strokes to get there....... do all the rest the same way.
Senior User
Joined: Feb 2007
Posts: 426
Likes: 0
From: Pukalani, HI
Some that have bought the HF set haven't been happy with it (I got one and have not used it yet). Make sure the correct adapter is included. The one I got had to be modified to work. Some have also had the gauge fail after only a couple of cylinders.... May want to get a quality set to start with.
