I'm replacing the power steering pump – again – on my 2003 Chevy 190 Popular, and took a few photos to show y'all a bit about the process. I'm getting good at this – it's the fourth pump that's been on there.
This isn't really a reliability problem – none of the pumps have ever actually failed. I replaced the original pump three years ago rather than fix a leaking front seal. Power steering leaks are annoying and also will adversely affect serpentine belt life, since the front seal leaks onto the back of the power steering pulley, which slings fluid all over as it spins, with some getting on the belt. At $30 for a rebuilt pump and no press or other fancy equipment to disassemble the pump and replace the seal, it's a no-brainer just to replace the pump.
This replacement pump worked fine for three years, until that evil Jim Hammill talked me into staying up in Canada long past the time when anyone with any sense would have headed south. At -10 degrees Fahrenheit, I started getting bearing chatter on cold starts. It went away in a minute or two, and never showed up at all at a balmy +10 degrees, but it's a sealed bearing, and a chattering bearing means that eventually it will heat up and fail. I had a 2000 kilometer drive back to Florida, with snow lining the road for the first half of it, and I didn't want any breakdowns, so we swapped it out at the factory before I left.
The pump that went in at Kitchener was also rebuilt, and had a fair amount of gear noise right off the bat. Gear noise didn't bother me the way bearing noise did when I was anxious to get down to Florida, because the gears are operating in fluid and any excess heat will be dissipated, and to my relief it uneventfully made noise all the way down to Florida. I hoped the gear noise would go away as it seated in, but it was still as noisy as ever after six weeks and 2500 miles, so I decided to swap it out for another one now that I have lots of time, good weather, and a friendly driveway to work in. That's the current project.
Modern vehicles remind me of Mattel toys- you take off all these huge plastic pieces and voila, there's the engine, exposed and easy to work on. Here's some of the plastic stuff – air filter housing and the tube connecting the air filter housing to the throttle body on the left, and fan and upper fan shroud on the right, along with the serpentine belt and power steering pump pulley.
Ah, the serpentine belt. Much mystery surrounds this fabled automotive part, and all it really is is a big flat ribbed belt, reinforced like a tire, that drives a whole bunch of accessory components. Back in the old days, cars had several V-belts, each driving one or two accessory components off the crankshaft, so the crankshaft pulley had three or even four V-slots for belts. When one broke or needed replacement, you had to take all the other belts in front of it off, which was a major pain because the accessory components would be on two pivot bolts and a third bolt on an adjustment arm, all of which had to be loosened, adjusted, and tightened. For each belt. A serpentine belt goes on and off in a flash, is self-tensioning, and is an overall quantum leap in automotive design.
Here's a photo of the front of the Vortec 6.0 liter engine, with the fan and fan shroud removed so you can see the serpentine belt. Pretty, isn't it? OK, I'm getting a little carried away, but the point is even the most callous non-automotive type will have to admit that it looks spiffy. Crankshaft pulley is the big one at bottom center. The serpentine belt goes from there clockwise up to the tensioning pulley, around the engine generator at upper left, under the idler pulley, over the alternator at upper right, down to the power steering pump lower right, and then a big loop-de-loop around that center pulley, which is the water pump and fan. You can drive low-load components like water pumps with the flat side of the belt as long as it covers at least 60-70% of the circumference of the pulley. Pretty slick, no? Now, since the engine generator is secret Area 51 stuff, forget everything you've seen in this photo.
The neatest thing is that you never have to adjust the belt tension like you did with the old V-belts. See that square projection on the left side of the tensioning pulley? Grab it with a 19 mm wrench and push down, and you're compressing the spring that tensions the belt. The whole belt will slip right off the pulleys and uncoil like an anaconda, and with this one tool you can put a new belt on in five minutes – ten if it's dark or raining. You can even work on a hot engine because you really don't have to touch anything if you're careful. Even if you can't change a tire, you can at least change the serpentine belt. All you need to know is how it's routed – which pulleys it goes over, and which it goes under. If your car doesn't have a belt diagram in a decal under the hood or in the owner's manual, draw yourself one in case you need it.