Replacing the water pump in a 3.9L, help please

[GRNDHOG]

Well the truck isn't even a month old yet and I'm already starting to replace parts on it. I hope this doesn't start a trend already!

Anyway, I bought the new water pump today and started to remove the old one and haven't got far, until I can get a tool I need tomorrow (for the clutch fan)

So my question is: is the the right steps I need? Can anyone give me tips to help the process.

-Drain the coolant
-I remove the fan/fan shroud. I need the fan removal tool, I'll rent one from Auto Zone
-Disconnect the hoses
-remove serpentine belt (WHICH WAY DOES THE TENSION PULLEY MOVE, TO LOOSEN IT?)
-Unbolt the water pump

Reverse steps to install new one.

I'm going to replace the tstat while I'm at it. I got a 180* thinking it'll be more beneficial here in the Florida heat. Will this be ok for my application? Should I have gone with the 160? It really doesn't need that much for heating, I'm way south in FL.


Again, any tips, how-tos, etc will be appreciated as I'm not the most mechanincally inclined person.

fyi, its a 1997 3.9L 2wd Auto transmission.

thanks all

[suffolk_mopar]

Well the truck isn't even a month old yet and I'm already starting to replace parts on it. I hope this doesn't start a trend already!

Anyway, I bought the new water pump today and started to remove the old one and haven't got far, until I can get a tool I need tomorrow (for the clutch fan)

So my question is: is the the right steps I need? Can anyone give me tips to help the process.

-Drain the coolant
-I remove the fan/fan shroud. I need the fan removal tool, I'll rent one from Auto Zone
-Disconnect the hoses
-remove serpentine belt (WHICH WAY DOES THE TENSION PULLEY MOVE, TO LOOSEN IT?)
-Unbolt the water pump

Reverse steps to install new one.

I'm going to replace the tstat while I'm at it. I got a 180* thinking it'll be more beneficial here in the Florida heat. Will this be ok for my application? Should I have gone with the 160? It really doesn't need that much for heating, I'm way south in FL.


Again, any tips, how-tos, etc will be appreciated as I'm not the most mechanincally inclined person.

fyi, its a 1997 3.9L 2wd Auto transmission.

thanks all



1. 180 t-stat is just what ya need.
2. standing outside the passenger fender the belt tensioner has to be pushed towards the driver side in order to get the belt off.
3. my friend and i used a adjustable wrench to remove the fan. i had to hold the fan to keep it from spinning while he loosened the bolt. same thing when putting it back on.

[chester_peabody]

The loaner tool autozone stocks won't work. You just need an adjustable wrench that'll go as big as the nut. I put the wrench on (while the belt was still there kinda holding it) and wacked (the wrench) with a big hammer. It came loose after a bit of work. The pump is a pretty common repair we have to do @ 100,000-150,000 miles

[razman131]

you might also have to move the alt and A/C comp and remove the accesory bracket to do the bypass hose. only a $5 part.

depending on what ywar pump you get, the heater core supply port might be a diff size than what you had. found that out as i had to replace my water pump friday night (mine was smaller than the one on the pump). had to uswe lots of *The Right Stuff* to seal the hole.

[GRNDHOG]

thanks for the input guys!

Chester, sadly, the truck only has 52,000 miles:( But its still 8 years old.

I guess it won't be a big deal if I have to move any more accessories, the biggest thing will be getting that fan/shroud off.

I was using a 12" adjustable wrench (on the fan) and it wasn't able to open wide enough. I guess I could go and look around to see if I can find an even bigger one. That reminds me.

The Haynes manual says its a "right hand thread" That means its a "regular" type bolt. Righty tighty, lefty loosey thing. Correct?

I always forget which one is backwards or forwards

[suffolk_mopar]

righty tighty lefty loosey...... facing the motor from the front bumper.


also, that lil 6 inch hose that someone mentioned earlier...... ya might as well go ahead and replace that. a buddy of mine replaced his water pump only to have that hose to bust a week later.

[GRNDHOG]

whats that hose called, exactly. I'll ask for one today

[razman131]

whats that hose called, exactly. I'll ask for one today


just ask for a bypass hose, they will know what ya is talking about.

[GRNDHOG]

ok, I'm super stuck.

I can't get the clutch fan off of the pulley.

For the life of me, I can't get that pulley to sit still while I turn the large nut on the fan.

I bought the $15 tool from Advance auto parts (although it says its for a Ford) Apparently the only tool Advance and Auto Zone carries is for a Ford. They don't even list a Dodge or any other make for that matter. The wrench fits but the "crowfoot" that prevents it from moving doesn't come close.

Does anyone have any suggestions on how to prevent the pulley from turning so I can turn the large fan nut?!

[suffolk_mopar]

hold the fan, or rather have someone else to hold the fan to keep it from turning. or ya could wedge a screwdriver in one of the holes and hold it. ( one of the holes on the pulley)

[RRDakota]

On my 99 3.9, there's a clutch, so holding the fan does no good......I've seen repies from other sources to use a vice grip on the pully,...It's stamped sheet metal, bend it & you are in trouble...The holes in the pulleys are not all the same size or distance(my OEM were 1/4" x 1 3/4 apart, the New replacement was smaller holes further apart)...The BEST TIP FOUND was to hit the nut (1 7/16) with an impact for a couple short burts @ 60# (low pressure) with a flat punch tool.......WORKED GREAT!!...I unthreaded the nut with my FINGERS....RH thread loosened to the left......No impact?? try a hammer & drift punch a few times to shock it......

[sltdak]

On my 99 3.9, there's a clutch, so holding the fan does no good......I've seen repies from other sources to use a vice grip on the pully,...It's stamped sheet metal, bend it & you are in trouble...The holes in the pulleys are not all the same size or distance(my OEM were 1/4" x 1 3/4 apart, the New replacement was smaller holes further apart)...The BEST TIP FOUND was to hit the nut (1 7/16) with an impact for a couple short burts @ 60# (low pressure) with a flat punch tool.......WORKED GREAT!!...I unthreaded the nut with my FINGERS....RH thread loosened to the left......No impact?? try a hammer & drift punch a few times to shock it......

That should work for you. On mine, I used two allen wrenches in two of the holes on the pulley and a screwdriver to stop them from moving while I turned the big nut with the AutoZone loaner wrench.

[RRDakota]

Speaking of Autozone....They partnered with AllData.com, the online factory repair manual info supplier.....You can get free directions from a factory manual for repairs...in another thread I read that Alldata pay service is usually free @ libraries...PITAss to find topic on autozones version, but there @ Alldatacom.....They reccommended buying a steel bar stock & drilling 1/4" hole in the end for a bolt through the bar & pulley.....seems like your allen wrench idea would work there too in the holes

[realdeal7369]

this helps greatly.

http://www.amazon.com/K-D-Tools-3472-Clutch-Wrench/dp/B0002SRGE8/ref=sr_1_49?ie=UTF8&s=automotive&qid=1226622715&sr=1-49

the universal tool ( http://www.kd-tools.com/3472.htm )has both the hooks on the end (so you have to loosen the pully bolts, lay that tool on, then tighten the bolts onto the tool..). or if there is no bolts holding the pully on, the universal tool has pins that set into the holes premade into the pully. simply placing that in there, then useing the wrench with the kit, or a big ass cresent wrench, will break it loose.

hold the pully holder tool with your left hand, cresent wrench with the right. pull up on the left hand, and down with the cresent wrench.

i believe the fan nut is a 32mm nut.

[kowboydmac]

Can you use a stock water pump if you get an electric fan?

[sltdak]

I don't see why not. You would just either make sure there is room for both if you run both the e fan and the clutch fan or just leave the clutch fan off. I think someone mentioned that the stock water pumps aren't the limits of our cooling system.

[kowboydmac]

I'm pretty sure with the 360 you can, just wanted to make sure the 239 you could as well. These blocks can also adapt to any 318 part as well right? even the stock piston size of a 318 can just slide into a stock 239?

[adobe wall]

Wanted to post a thanks for this thread. Gave me a good idea of what was involved and how to proceed.

A couple of notes. My truck is a 2002 3.9 The job took me two evenings, total of about 7 hours. I was working alone and wasn't trying to set a new speed record on the job.

The two biggest headaches were getting the fan shroud off and the fan clutch nut. After I took the fan shroud nuts off, there was still a plastic connector that I couldn't reach. I ended up just yarding the shroud out with a good bit of grunting and cussing. Needless to say I didn't replace that fastener.

The fan nut would have been a deal breaker if it wasn't for this thread. I tried using allen wrenches through the pulley holes but that didn't work for me. I ended up taking a piece of flat steel and drilling 2 quarter inch holes 3 1/8" apart center to center. Put a 3/4" long, quarter inch bolt through each hole and secured with nuts. That worked fine, held that tool with my left hand and used a 15" adjustable wrench on the fan nut with my right hand. The big adjustable was $9.99 at Harbor Freight.

Other than that, it was just taking parts off and putting them back on. Thanks for the heads up about the bypass hose, that was a good tip.

I was a little baffled by the small supply hardpipe that sticks out of the driver side of the water pump. That tube had to be installed into the new water pump but I didn't really understand how it was secured. There was an o-ring in with the water pump but there didn't appear to be a recess in the tube to hold the o-ring. Turns out the old o-ring was basically baked onto the pipe, once I figured that out the new o-ring went right into place.

Also good to swap out the thermostat at the same time as someone pointed out, only a few more dollars and it's one less thing that will need to be replaced later.

Everything went back together smoothly and truck is running fine with no leaks. Any thoughts on how much in labor I would have paid for this job?

regards, aw

[bch]

I know kinda late now. New member here. on my 99 Dakota I used a rubber strap wrench to hold the pulley and whacked the wrench with a bfh a few times and it came right off

[Cmucky]

When your engine ran did it have a small tick to it? If you answered yes you might want to replace the timing chain set and throw in a timing chain tensioner. If you need details om how these are down just let me know. Done it to both of my 3.9's already.

[aspen79]

What if it has more like a rattle at a no-load idle? I think it's time to finally replace the chain and put in a tensioner. Actually, it sounds no worse now at 125,000 than it did when I bought the truck 11 years ago with 49,000 miles but it's probably gotten worse so gradual, I just didn't notice the change.

Did you use Mopar parts from the dealer or aftermarket?

[tanktop8]

"Try placing a bar or screw driver between the water pump pulley bolts to keep the pulley from rotating." This is what my factory service manual says. I actually will be doing my water pump this weekend for the first time... should be interesting. From what I've read and heard get the bypass hose, and a new heater core nipple. Some heater core nipples thread in and I think some press in, this will be on the water pump too. Once you get that nut off you are going to remove the fan blade assembly and the fan shroud together at the same time. The only way to get them out is together, and there will be less chance of damaging the radiator as well.