I have always had good luck with GMB so thats what i buy.

I bought a Flow Kooler water pump for my 4.0 back in 2003ish. Back then they just had a metal plate riveted onto the impeller and charged $120 for the damn thing. I bought it anyways because i always like to upgrade when i have to replace stuff. Shortly there after i bought a $25 GMB to replace the water pump on another jeep i had. When i started looking at it it was the same exact casting as the GMB. So all Flow Kooler did was rivet a plate on the impeller and charge an extra $100.

There is also a high performance GMB water pump but it always gets bad reviews saying it don't fit because the impeller hits the block. I never tried using it but i imagine that it has a plate riveted onto a standard pump to increase coolant flow. The Flow Kooler (GMB) came with a thick gasket and a regular gasket. The instructions said if the impeller hit the block to space it out more with either the thicker gasket or use both gaskets. Mine did not have any interference issues so i used the regular thin gasket and it's still on my jeep today.

The GMB pumps have this weird machined out area where the heater hose pipe comes out that is filled in with a aluminum plate and they are the only ones i see made like that and i have replaced a lot of 4.0/258/2.5 water pumps.

 

Avoid the box stores if at all possible you’re going to pay double what you would on Rockauto or amazon . Seems weird but I’d go with the AC Delco as a first option or Gates as a second off Rockauto .

 

Gates don't make water pumps they just repackage them and sell them as their own and idk about AC Delco i imagine they do the same thing. GMB does have a cheap price but the reviews are always good so i wouldn't let the low price scare you they seem to make a good product i have never had one fail and Flow Kooler put their name on it. Mine is still going 15 years after i installed it so they have to be doing something right. I have been needing to replace the water pump on my dads dodge ram soon and im going to be going with GMB.


I had the water pump go bad on my 89 Comanche with a 2.5 once. I went to the local mom and pop parts store and bought whatever pump they had in stock i dont even remember the brand whatever it was was crazy cheap. I got it home and went to put it on and the holes were all drilled wrong and it was clocked to far to one side and the inlet hit the block and the power steering bolt holes were noticeably off. I took it back and they gave me another and i put it on and all was good for about 2 weeks.

Then one day i got home and as the engine was cooling down i was working on something in the garage when i hear water splashing and i look up and its coming out of my MJ. I never seen a water pump seal fail that miserably in all my life it hadn't even weeped before it started gushing allover the ground. Both of theses pumps looked poorly made just looking at the casting and machine work you could tell they were junk. After that i put a GMB on it and never had another problem.

 

Thanks fellas. Hopefully soon I can get a good look at it and get one on order.

agalloch07 Is this the area youre referring to about the machined out area on the GMB pump?

Are the GATES, AIRTEX, DURA-GO,CARDONE SELECT, or AC Delco Just as good?
Which one is close to the original OEM style? Not that it matters but was looking for the best easiest fitment/replacement.

Its sounds like I should stay away from the GMB High Performance pump for $50.

 

No this area, GMB are the only pumps you will see that on as well as the old style flow koolers. Flow koolers are different now though i think they have billet impellers so idk if they still use GMB pumps, they might though.

 

Other pumps wont have that like the one in this picture, i thought it was kinda cheap looking when i seen it and though it would cause leaks but it don't. I replaced mine back in the early 2000's and it's still going i don't think it will ever die it has outlasted the factory pump.

 

Okay much thanks. So your recommendation would be this one then? The GMB 1101090 for $16.62. Im wondering if it comes with a gasket(the picture shows one) like the Gates 42005 states in the description..

Did you replace the fan clutch at the same time? I just re-read the GMB description & they recommend it. If so what one did ya go with? Any problems?

 

It probably comes with a gasket but i always buy a felpro gasket because they seem to be of higher quality than others (some cheap ones feel like they are made from a cardboard cereal box). And i don't have a fan clutch i run a flex fan

 

Much thanks.

 

I bought a aftermarket water pump from Napa. I believe its a Napa brand "Tru-Flow". My mistake I painted it before I tested it. The fan pulley does not line up with the drive pulley and as you can see the pulley is very close to the housing of the pump. Can I use washers to move that away from the motor to line up the two pulleys? Anyone had similar issues? Thanks

BTW the jeep dealership here in San Diego reports you can no longer get OEM water pumps.

 

Is that a 2.5 liter?

I have never owned a 2.5L YJ but i had a MJ with one and the pumps were longer. The pulley in that pic looks nothing like the pulley on my 4.0 and it looks like it has a cast iron exhaust manifold so i am assuming it is a 2.5.

If the pulley don't align they probably goofed and gave you a 4.0 water pump.


Also, never paint aluminum it don't radiate heat as well leave it unpainted. It's not going to rust or anything anyways so there is no reason to paint it. Every time i see someone paint a aluminum transmission or transfer case i cringe.

 

Good to know about the paint. Thanks .
This is on a 1989 4.2

I guess I will be looking for another waterpump.

 

I’ve had good luck with the car quest brand water pumps. Advanced auto parts now owns carquest so you can get all carquest stuff at advanced. The store will be more money then rockauto but at least if you do have a failure you can return to the store and they’ll give you another one.