Replacing or changing the high pressure oil pump in a vehicle is a lot like changing the oil itself. Most of the steps are the same until you get to replacing the HPOP. It’s not a difficult procedure and if you are do-it-yourselfer, you will save yourself a decent chunk of change.
- Do not change the HPOP outside. There is too much potential and too many ways for dirt to enter the engine if you do this outside. Inside your garage is much, much better.
- Put the parking brake on and jack up the car underneath the axles. It’s easy to see why auto manufacturers don’t want mechanics to do this with only the frame as support, especially if you’re changing the HPOP on a two ton truck. If it lets go, a car would kill you; what do you think a truck would do?
- Drain the oil. Yep, just like changing the oil, let it all drain out. Having an oil drain pan might be a good idea here.
- Locate the HPOP. It will be close to the back of the engine. In a diesel there should be one or two hoses connected to it too.
- Remove the mounting bolt or bolts. Again, it depends on what you’re working on; most cars will have one mounting bolt while trucks and diesels will have two. On a diesel you may have to disconnect the pump’s hoses to get to the pump.
- On some models you might have to remove the oil pan to get to the pump. Otherwise, you might not be able to locate the pump.
- Remove the pump. If the pump needs lubrication before installation or any other special instructions make sure you follow them to the letter or you’re going to have to repeat this process.
- Once installed, put everything else back into place. Then change the oil and refill.
That’s it; it’s a piece of cake. The process is a little more intense for diesel engines, and has a few extra steps, but the basic procedure is the same.