US General (Harbor Freight) Diesel Compression Tester

Cougar281

Well-known member
Sep 11, 2006
1,758
216
63
St Louis, MO
Does anyone else have this tester and tired it on a LBZ? When I used it on my LLY way back, the LLY adapter worked perfect. On the LBZ, when I tried running the LBZ probe into the head, the "head" of the adapter hits the head casting before it's seated. In looking at my LLY heads and LBZ heads, the LLY has a nice "countersink" all around the plug, but on the LBZ, it's not straight in, and one side of the plug sits pretty close to the head. It's like the adapter needs to be longer. Any thoughts?
 

emiller3

He's Back
Feb 21, 2009
3,586
0
36
42
lake charles,LA.
I have one and had the same problem.Lengthening seems like it would help.I ended up just putting a little teflon tape and called it good.:eek:
 

JoshH

Daggum farm truck
Staff member
Vendor/Sponsor
Feb 14, 2007
13,605
639
113
Texas!!!
It's because the on LLY glow plugs the threads are up at the top of the shank just below the head, but on the LBZ, they are about half way down the shank. I took one of my glow plugs and a LB7/LLY glow plug adapter to a machine shop and had them make me one.