LEAKDOWN TEST

[larso1]

Norm, I did a leak down test on my Iseki 2-cyl. diesel. I used a leak down test kit which was composed of gages, tubing and fittings. I borrowed it from a friend who owns a automotive and small diesel repair shop. As I remember, the gages gave inlet pressure from the compressor and the other gave leak down in %. Instead of finding a fitting for the big threaded injector hole, I had a smaller fitting made up that connects to the threaded glow plug hole. My front cylinder was reading at 22% and the rear was at 38% (kind of high leakage past the rings). After I did the test he told me I should have done the test with the piston at BDC, middle of the cylinder, and TDC. I let the air push the piston down and took my readings only at BDC. I have since replaced the rings and rod bearings with the block in place on the tractor. Worked very well and didn't have to deal with the high pressures of a compression test (450psi+), which he said was not nearly as conclusive.

Bill in CO

 

[normde2001]

"After I did the test he told me I should have done the test with the piston at BDC, middle of the cylinder,"

I would guess any time both valves are closed would be a good time.

 

[larso1]

Valves were not an issue. I had backed off the lifter adjusters so there was no way they would open. The issue was the cylinder bores do not wear the same at the top as they do the bottom. I'm sure you know that.

Bill in CO

 

[normde2001]

"The issue was the cylinder bores do not wear the same at the top as they do the bottom."

Good point. Gotta admit, I had not thought of it.