CAT ET Software (and head problems)

[Rawze]

(04-30-2020 )tsolson Wrote:  Thanks.
I made a plate for the intake and installed a pressure gauge and a schrader valve. I pressurized the intake up to 35 psi and I can hear air leaking. Sounds like cyl #5 air leaking the loudest. Pressure will leak down from 30 to 20 psi in about 10 seconds. Not sure how long it should hold pressure? I’m going to pull the injector and try pressuring the one cyl to see if I can pinpoint it. I’m guessing the new head I got was no good, that would be my luck.

make sure the intake rockers are up and that valves are all closed. After that , if it is leaking any air at all, it is bad. - An ISX head that is good will hold 30 psi for an hour or more before the needle drops. There should be no consistently measurable leak rate, and certianly nothign like you describe.

same for the exhaust side.

-- A new head can be checked before install by doing same test on intake and then exhaust side. - Some people will turn the head up on its side and pour liberal amounts of brake cleaner, penetrating oil, sometimes diesel fuel or gasoline into the open valve ports and let it sit several minutes to see if liquid seeps around the valves on the head... then turn it to the other side and do the same test again.

Personally, I like using air pressure instead. It catches more problems than using liquids that are not pressurized.