How The 7.3L Power Stroke HPOP Works
In the mid-1990s, tightening particulate matter emissions standards gave birth to the hydraulically actuated electronic controlled unit injector system we all know as HEUI. One of the engine’s to debut the new injection technology, which Caterpillar leased to Navistar, was the 7.3L Power Stroke. In the past, we’ve detailed the makeup of an oil-fired HEUI injector at length, but what about the other piece of the puzzle, the high-pressure oil pump? As we close in on 30 years since HEUI was introduced, many still don’t know the inner workings of an HPOP. What’s more is that a lot of 7.3L enthusiasts have never even seen inside a high-pressure oil pump.
This month we’re taking an in-depth look at the 7.3L HPOP. We’ll show you all the components packed within its compact housing, how they work together to provide oil volume, and highlight the electrically operated dump valve that controls injection control pressure (the IPR). Ever wondered what the difference is between a “15-degree” and a “17-degree” HPOP? Keep reading. After we distinguish the difference between the early and late high-pressure oil pumps, we’ll cover some of the modifications that allow an HPOP to produce more oil volume in order to support larger injectors. Let’s dig in…

























SOURCEs
DieselSite
888.414.3457
dieselsite.com
Full Force Diesel
615.962.8291
shop.fullforcediesel.com
Riffraff Diesel Performance
541.879.1052
riffraffdiesel.com
Swamps Motorsports
615.640.6273
swampsmotorsports.com
Terminator Engineering
terminatorengineering.net