Hey I have a 94 7.3 turbo diesel 145,000 original miles bone stock as far as I know. The truck was missing alittle so I checked the compression and all the cylinders were all at 400 lbs or little higher exept for cylinder one which was around 270 lbs I was wondering what people kinda thought what would probly be the cause for the low compression such as the piston rings, or maybe worn cylinder and if there was away to fix the compression by leaving the engine in the truck even if I had to resleeve it thanks

 

You might have a leaking head gasket (or cavitation ). Check for bubbles in the coolant while running. That would be the first place I would look.

If you have a cylinder leakdown tester you can hook shop air to that cylinder when it is at TDC compression to determine where it is going.

If the block needs to be resleeved, you will have to remove and disassemble the engine.

Jason

 

Check the valves on that cylinder....... compress them slightly 1/4 inch then see if the have significant side play...... Also check the push rods for straight and the rocker assy for excess wear.

 

Just curious, how do you check the compression in a diesel? You don't put the tester in the spark plug hole...

Sorry, I'm a gasser guy...

 

On most testers that I have seen, you remove the glow plugs and install the adaptor into their holes.

Jason

 

Ah. Well, now I know.

Thanks.