A fast ride along while I remove the HP4 out of my 2021 Chevy 3500HD 6.6L L5P Duramax. This is the first time I've tackled an HP4 replacement. #duramax #chevrolet #diesel #l5p #injectionpump #hp4 #chevy #dieseltrucks #mechanic #diy
Why do u think the pump is bad on the 2021? No external leaks and if it failed internally u need to go through more components and clean. Did the truck run? Give an update and what symptoms were present before u pulled pump please.
@@Juan-tj1bf if you have metal in the system, it’s going to be in every part of the system, so you can always do what you wish but chances are there’s going to be more failures with a contaminated system
The cp3 was just about bulletproof. I also replaced the one on my lbz around 250k. It didn’t need it but I was chasing some other fuel issues and had it tore apart anyway. I wish they’d go back, but the cp3 doesn’t make enough rail pressure. But you can do a cp3 conversion on the l5p with some tuning. They really should figure thes new pumps out because they all haven’t even come close to the reliability of the cp3
@@PartTime_Pro Yes like turning on a water hose Every time I see this on other diesel engines, it's bad injectors. This truck also had a full tank of water in the fuel system.
@@jeremybrown7475 yea, that definitely seems excessive. You’ll have to look it up but there is a test you can do where you measure the amount fuel return and see if it’s within tolerance or not. There is a spec for the complete system and a test where you measure each injector individually.
@@PartTime_Pro I have looked into the test and its a vary small amout that is measured it showed 40 ml in 15 sec of cranking im Pretty sure. I have more than that
Basically if the truck was being serviced and there was less than 25% life left on fuel filter we’d change the fuel filter at that time. So not quite waiting till zero but not exactly 2x either. And yes we always use fuel additives, either power service or hotshot secret, and Lucas system cleaner once every couple of weeks.
@@thomasmoix1446 i have Heard of lots of these hp4 pumps failing. Not quite as bad a the cp4 failures but still common failure point. Be nice if they’d just go back to the cp3 pumps.
@@thomasmoix1446 from what I hear the newer fords are having worse fuel failures, transmission problems, and lots of electrical little issues. Dodges I’m hearing tranny, emission components, and I’ve met a handful of guys who have had complete engine failures due to camshaft/lifter issues, and also that heater grid bolt that will fall into the intake. But I’ve never and will probably never own a ford or dodge, so this is just what I hear.
