Ben Bryan

So far, I've read about ten threads on this forum alone, in addition to some elsewhere, where water pumps were being discussed, and I must admit that I'm at least as lost as I was before. A great deal of the information seems to be subjective, and I can't seem to find a clear answer where one brand or source is better than another. So I'd like to try a different approach to the subject in this thread.

Instead of a typical discussion, riddled with opinions and "I'm going to try this next time", I just want to hear your success and failure stories, along with the water pump you installed, and any other parts that you think are necessary to mention.

In context, I'm trying to choose a path to solve my cooling system issue, and I simply want to use reliable parts that work. My (other) jeep is a 2001 XJ with a Jasper 4.0 engine, due to the catastrophic failure of the original engine (0331 head). I believe my current issues may have something to do with the fact that all the original peripherals including the water pump were used on the new engine. At the time, I had believed that the failure of the original engine was solely due to the failure of the thermostat, which closed when it failed. But now I am questioning the pump and the fan clutch, as the issue only occurs at idle after the engine is up to temp, and has done so ever since the new engine was installed. As a cheap hold-over "solution", I installed a 160-degree thermostat, which turned out to be a mistake because it killed the gas mileage (ECM sees that the engine isn't warm yet so it sends more fuel), but it also STILL runs hot at idle.

Again, not really looking for a big discussion here yet, but rather your water pump stories.

Thanks!

Turbo X_J

Temps verified with an IR heatgun?
Thermostat only provides for a minimum engine temperature. It costs ~$200 to replace the entire cooling system, go for it, other than a MoPile thermostat brands doesn't matter.

Ben Bryan

I think I just wasted a lot of typing.

ReptarXJ

Hi,
I purchased my 96 XJ 2wd 2 weeks ago and had some overheating issues. where it would go over 240* during city or highway driving. When I replaced everything I found out the Previous Owner removed the thermostat! Since I already had everything opened up I went ahead with replacing everything listed below since the coolant flushing was not getting rid of the brown dirty water. Prior to deciding to replace everything I made sure my headgasket wasn't cracked by using a which turned out negative.
So I decided to replace my waterpump last week due to overheating issues along with a new thermostat housing, thermostat and radiator. I never installed any of those components before on any vehicle but there were so many resources out there on youtube it made it seem easy.

Here is exactly everything I replaced along with the help of these Youtube videos

I also purchased which i would recommend buying 2 of them. I only purchased one and it was barely enough. Always better to have more than less.
Youtube:
With everything It took be about 3 actual hours of work. I did let the RTV on the water pump and thermostat housing cure overnight but I was probably being overly cautious. I've read elsewhere 2 hours to let it cure should be enough. I just worried about it leaking and having to pull everything back out again. If you were to only replace the water pump and thermostat itself I would estimate about an hour for simply installing those two components.




I may have went a little overboard but to be honest I am glad I installed everything. For under $200 and piece of mind the engine won't overheat it was worth the time and money. Its been about a week now with all sorts of driving and has held up well and stays considerably "Ice Cold".

J_Irish85

I agree I would like to see a big discussion here as I am also curious like you are. I've never don't a water pump on my 4.0 yet lol knock on wood. So this is a bump come on people let's hear them stories.

EZEARL

Replaced my entire cooling system except for the heater core in Nov. of 2016. Also replaced the serpentine belt and idler pulley. Used a Gates water pump,Napa fan clutch,and MOPAR 195* thermostat. Since then I've been able to leave the vehicle idle for extended periods of time in the hottest weather with the a/c on.

CoffeeCommando

YOu spend some money but you did it right. SOmething else that heavily needs addressed that most people don't ever mention is that bottom radiator hose.

Spend the actual $50~ instead of $15 and get one with a spring in it. Even pretty new those suckers kind of collapse, and that bottlenecks the cooling system.

If your vehicle overheats on the highway, you have a water pump/lower hose problem. Since the Jeep engine isn't bimetal (aluminum head on an iron block) it's not likely a withered away pump. The combination of an aluminum and iron mixture with old coolant will eat up the impeller on water pumps.

..but that hose is almost always a problem. If your hose is easily collapsible either while cooler or while driving, it needs upgraded. If yours doesn't have a spring inside that's the FIRST thing you need to replace, and if you've ever overheated you should go ahead and replace the cap with a quality one.

If your vehicle overheats idling, it could also be the above, or it's a fan issue. My fan doesn't operate properly which means it rotates 24/7 with the vehicle one which gives more cooling so I am not concerned. If yours doesn't spin at all... that's a problem. Also, if that electric fan doesn't kick on soon after you turn on the AC and you're at operating temperature that's a problem. I replaced mine with a jeep grand cherokee (had to do some soldering) because mine was just plain weak. I have a supercharged stroker engine and that ZJ/WJ fan works much better. I got it from a junk yard years ago. I highly recommend if you're looking for something to do, or if you need it.

5-Speed

I myself have never had an over heating issue with any of my XJs that I have owned. This could be because the first thing I do when I get one is replace everything. Call it preventative maintenance if you would like. I do it the cheap way though. $50 radiator off Ebay, Duralast pump, new hoses and a Stant 195° thermostat. Its only about $100 in parts so I dont mind taking the gamble. Both my current XJs run a hair over 200° now.

A suggestion of mine, if you are going to overhaul the whole system, run a bottle of flush through it first. That way any big chucks that come out get stuck in the old radiator instead of the new one.

LadyKenai

94 xj, after replacing water pump (40$ oreilly cant remember the brand) i 'thought' i still had an overheating issue but it was my temerature guage sender on the back on the head that was indicating higher temperature than it originally was at least 10 to 15 degress higher, once that was replaced the auxilary fan actually turned on at the right temperature i was fooled thinking the engine was hotter than it indicated. the engine stay on right temperature now and will see how long this pump will last, if you want garantee and higher standard quality buy oem parts.

marc

BlueRidgeMark

Don't get too spun up about the brand of the water pump. NAPA is fine, just do it.

T-stat should be Mopar, though.

By the way, no way would I EVER replace an engine and put an old water pump and hoses on it. They just aren't that expensive.

If you take Turbo's excellent advice, and you are still running hot, take a very close look at that engine. Jasper is not high quality.

Ben Bryan

I guess it was silly to try to define the type of thread I wanted. I'm full of silly ideas, you all will learn once you get to know me :-)

Right, so it wasn't my idea to re-use the original pump. The jeep had less than 90k miles when the OE engine blew up, and there was no "known" issue, so the mechanic just dropped it back in. He had several ASE certs (the reason I chose him to do the work) so I would assume he at least looked at the impeller before reinstalling it. It doesn't leak or grind or anything either.

But here's the shameful bit I left out... The engine was replaced 5 years ago, and I've just been carefully dealing with the issue and taking care to watch temps, suffering with it basically. Its only in the last couple years that I've taken a significant interest in vehicles, otherwise I would have fixed this long ago. But thats neither here nor there....

Don't knock my engine dude! :P As far as the Jasper quality, I find no problem with it. Its better than the OE engine for sure, in this case at least, and it runs smoother all around than the original engine, as well as my two other jeeps (87 wagoneer 4.0, 91 cherokee 4.0).

I have not checked the temps with an IR thermometer, but the OE gauge is very consistent and seems to be correct from what I can tell (before the OE engine failed, it always read around 205 on the highway, 210 in town or idling, extremely consistent and sensible numbers). Since the new engine and 160 t-stat, it runs 160 on the highway consistently unless its cold, and then its around 140. In town, it always runs around 180 unless its a hot day/lots of sitting in traffic, and then it goes up around 215, where it begins to run noticeably rougher. Any higher than that and it begins to pre-detonate, especially if you shut it off while hot and then restart it (duh). I can always keep it cool in these instances though, just by kicking it up to 1500-2000 RPM. The temp immediately drops and it runs better. This behavior is what made me think about the pump and mechanical fan to begin with. The 160 t-stat was installed a week after the new engine because it simply would not stay cool and there was no obvious reason why.

I do plan to replace everything except the radiator (because I already have) and the heater core (because it works fine, doesn't leak, etc). Just trying to build a parts list at this point. Here's where I'm at currently:

• Spring-lined upper and lower hoses - (haven't looked at any brands or prices)
• Temp sensor - ((haven't looked at any brands or prices)
• Thermostat - everyone seems to agree on mopar, and the reasoning makes perfect sense. This is about the only thing thats 100% clear...
• High flow thermostat housing - Hesco has one. I haven't really seen anyone say this upgrade is a mistake, so I guess its a good thing to do and a good time to do it.
• (high flow???) Water pump - This is where things get really foggy and information seems subjective. FlowKooler. I've seen some people swear by it, others condemn it. Mopar? Same deal. Hesco? Thats expensive but seems to be reliable. Duralast? You mean DuraRoulette! O'Reily's? You mean OhReally?'s! Napa?? Well thats a toss up too. Reman vs new OE vs new chinese, etc, etc. I would like to try a FlowKooler honestly, but the reviews seem mixed. I guess I'll just keep watching and eventually draw a name out of a hat :-)

Thanks for all the info and stories so far, I do appreciate it.

RocketMouse

Replaced the T-stat, t-stat housing, and water pump all at the same time....about 3 months ago.
I think it was the original parts on my 99 XJ with the 4.0.

Honestly, it was just about the easiest water pump replacement I've ever done on any vehicle. On my 99, I only had to take out the aux. electric fan to give me enough working room. I didn't even have to take the primary fan/clutch assembly off. Then before taking the belt loose, and using the old trusted leverage trick with a big-a** square shaft screwdriver in between the water pump pulley bolts, And easy peezy.... problem solved. Then soak the pump bolts good with pb-blaster/wd40, wait a few, then off they came with no big issues.
Only one that's a little bit of a PITA is when installing the new pump, getting the very bottom bolt in as you can't see where it goes, just have to go by feel and go slow so you don't risk cross-threading it. I probably spent more time soaking the bolts well than I did on the entire removal and re-install. I just wanted to be a bit more cautious on mine since I was pretty sure it was original to the Jeep. (I only have 99k on it).... so that I didn't risk breaking any of the bolts off in the block.
It was fairly clear, but did give a gentle back-flush to the heater core while I had the hoses off.
As for the part. Brand new water pumps aren't that expensive, and it's such a vital part on the engine, why risk it with a reman? (IMHO)
Brand new, I think I spent like 40 bucks on it. I went with a good quality OEM one. Not that dura-crap stuff. As for the T-stat, just went for the correct one.
I know why mine was having issues and probably caused the pump to fail.... the previous owner of mine was an idiot and at some point had replaced only the T-stat. He didn't even bother to look at it and installed it the right direction, but upside down, so the air hole was 180 degrees out of correct position.
What a dork. That's the simplest part on a vehicle almost, and he even managed to mess that up.
I've already gone through it pretty well while I completed the projects it needed up front, like new front end, brakes all around, etc.

cruiser54

this^^ 83501426 or 52028186 Mopar stat only.

May have a letter suffix on the part number but that's okay. The first number comes with a gasket selection and the second number does not. https://www.ebay.com/p/Engine-Coolan...86AC/174775358

BlueRidgeMark

You got lucky then. Their quality control is.... less than admirable. They don't bother to match bearings or bores, for example. If a single cylinder needs to bored, they bore it and throw in an oversized piston to match. They won't touch the others, so you have mismatched bores. Same for bearings. You could wind up with a mix of stock, .10 over, .20 over, etc. They do only the bare minimum.

Ford quit using them for their 'factory' rebuilds due to quality problems.


Nah. Not needed. A properly working stock system will keep it running fine in Arizona temps, pulling a trailer up a hill in the summer. That's actual results from a few members here. The stock system will handle anything other than slow rock crawling in the desert.

It won't hurt, but it's not needed.

Waynerd

Went with NAPA pump, thermostat housing, heater hose tube(repackaged Dorman). Fel -Pro gaskets and NAPA/Stant thermostat. Had a used radiator and flushed everything well. First with cleaning additive and then a few with just water. Everything is great for about a year and a half now. Also threw on a used mechanical fan I had with no shroud. It actually takes a little long to get to full temp on extremely cold days and it runs a tad below 210 unless it's slow uphill in summer heat or long idle in summer heat then it's a tad above 210.

I just did one also where I swapped in a used one I had. Just a drain and fill. Used a Fel-Pro gasket. This Jeep is a 98 with 163k the first is a 98 with 215k. Also I flushed the heater core recently on the first 98. So glad I did.