Final Treatise on the Pumps of Big Burrito, Part the First

Having spent weeks combing through fields files with the bodies of wrecked land ships,  questing in search of tomes that exist mainly in whispers, legends, and rumors, and solving the mystic riddles and enchantments of protection lain on dark grimiores, I have returned from the land of pain and darkness to rejoin the land of the living and share what lies behind the veil of death.

Today I will be talking about power steering pumps.  A lot.  Grab a dose of your stimulant of choice and tuck in -- this will require some attention.

To recap: the AMC 258 was configured with a v-belt drive for a significant portion of its run, and the 242 was serpentine (unless there's an oddball configuration I'm unaware of that was v-belt).  Using the head from a 242 on a serp 258 requires either fabricating accessory mounting brackets, changing your belt drive type (including using a reverse-rotation water pump), or using a power steering pump compatible with the 242 mounting design and changing its pulley.  I'm covering the latter.

PUMP UP THE JAMS

For this subject, there's three types of steering pump to be aware of:

1. The Saginaw P Series pump. Ubiquitous for around 40 years, looks like a canned ham, and is what the Gremlin and probably any other power steering-equipped AMC came with.  Generally 3/4" input shaft.
2. The Saginaw TC style pump.  One of two base designs that are broadly referred to as "Type II", about the size of a baseball, found in XJs, ZJs, Ray Jays, and a ton of different year models of various foreign and domestic makes from the 80's and counting.  When doing a 4.0 head swap, this would be the style most-easily used.  Might as well get it with the head you pull from the yard and save time and a trip, because new units are priced well above what I think would be worth paying.  Generally 0.663" input shaft.
3. The CB style pump (or red herring).  Very similar to the TC, also referred to as a "Type II", can be used for some internal parts if needed, though largely useless for this use-case.  About as common as the TC pump, though variants of this design seem to be more wisely-used than the TC by foreign makes.  Usually ~0.705" input shaft, though this style seems to have the greatest variation in potential shaft diameter configurations.

Keep in mind that these are three very broad styles.  There's an incredible number of variants and derivates out there.  In the case of TC/CB pumps, the deeper you go, the more the lines can blur between assumed defining traits.  That's one big reason to stick with one from a Jeep, since it will save you a lot of headaches with fitment.  Don't worry, though; there's still plenty of hassle to deal with in getting the pump to actually operate appropriately with your original 800 series steering gear box, which I'll cover later.

PULLIN AROUND

I'll get this out the way: there are no OE pulleys on any make/model that will provide a v groove, and correct offset and bore diameter, at least none I've found over literal hours and hours of research.  Do yourself a favor and don't bother trying to find one.

The lack of junkyard or parts store options that meet the criteria I mentioned makes sourcing a nearby replacement nearly impossible.  This was a serious problem to me, but if you have more money than sense and don't care about getting parts shipped to you whenever you need them, good news: I've covered everything you need to know, so feel free to leave early or work on other assignments while the rest of us continue.

As explained, a Grand Cherokee is equipped with a TC pump, which has a shaft size of 0.663" and a serpentine belt pulley.  Pulleys of any drive type and that fit this pump have a bore of 0.662", making for one tough interference fit.  While some WJs provide a higher operating pressure than the other Jeep year models, the external features just described should be the same for XJs that are equipped with a type II (read, non-canned ham, Saginaw P series) pump.  All the same, I'm not a Jeep expert, so make sure you're up to speed on the differences between a TC and a CB pump if you start combing through XJs, just in case. 

Even though there are no press-on v-belt pulleys to be found at the yard or O'Partsy's that will fit our pumps, there may still be hope in the form of pumps that are fit with press-on hubs and bolt-on pulleys!

THEREIN LIES THE HUB

 I've found that there are a ton of Volkswagen year models from the past few decades that use a pressed hub which will provide mounting options for a myriad of v-belt pulleys of various diameters, almost all of which are about 15 bucks or less new.  If you want to stay with a domestic-themed brand, Ford Rangeplorers used a similar design, starting in the mid-to-late '90s.

Be aware that things get a little tricky with the VW pumps: I found that several of the Type II pumps used by VW (mostly CB) have a shaft size of 0.667", or just large enough to be useless on a Jeep steering pump.  If you're heading into German territory, as always, bring your calipers to the yard!

That brings me to the perils of Fording this river.  The Ford hubs *appear* to match the desired bore to mount to the 0.663" shaft, and also seem to match the bolt spacing used with the VW hubs.  Unfortunately,  I didn't discover this until after my last yard run, so didn't get a chance to measure.  Based on pictures comparing the Ford and Grand Cherokee pumps, these features should match.  Leaving a comment with details that settle these questions will be worth 10 extra credit points. 

Since there's no shortage of those Fords in the yards, and how much more easily accessible the pumps are in the Ford bays vs. the VWs, I suggest making them your first pick if you're doing the yard crawl.

CONCLUSION

I'm far from proud to admit that I had to grab an aftermarket pulley, though not because I preferred it over using a hub.  I'm so far out of time that I couldn't afford to keep chasing the yard option, while Eagle isn't up to making the drive for the distances going to the yard demands, and I've decided that I'm not giving my money to a company that treats their customers like Pick N Pull has repeatedly treated me and my friends.  If a replacement pulley is needed in the future, I'm definitely pursuing the hub option over trying to get another aftermarket part.

If you find that you end up having to go the aftermarket route, the cheapest option I found for a proper v-belt pulley is made by Sweet Manufacturing, P/N 301-30020.  At present, they can be found for roughly $35+shipping, which is a bit easier to swallow than what people charge for other parts that don't even have a collar to fit a puller onto.

So there you go! The info in this post should be all you need to mount a late-model power steering pump to a 4.0L head and tie a rubber band around it's wheel.  The upcoming second part of this. . . article(?) will cover how to make it feed the pressure your steering gear was designed to receive.  I think.