Grand Cherokee WJ I6 Water Pump
If you are like me, then replacing a water pump doesn't sound like that
much fun, but you would rather do it yourself than pay someone else to
Replacing the water pump on your WJ isn't
to be that hard, but a
little help with the steps would probably be nice.
we begin, a couple of warnings:
the cylinder block drain plugs, radiator cap or open the petcock while
the engine is hot or the cooling system is under pressure. You're
likely to burn yourself. Also, antifreeze is poisonous. Children and
animals are attracted to it due to the color and odor. If you suspect a
child has consumed any antifreeze, immediately call 911 or your local
poison control center.
This write up will hopefully give you some
pointers that could save you
some time in the long run and make things a little easier for you.
1) Diagnosis. First thing you probably have
noticed is that puddle of
antifreeze on the ground in the morning. Check your hoses first and try
to determine where the leak is coming from. If it is indeed dripping
down the front of the engine block, check your hoses on the water pump
and thermostat housing once again, just to be sure (no sense in doing
more work than necessary here). If you are in the same boat I was,
water and coolant is probably seeping out of the weap hole of the water
pump. This is a good sign that your water pump is on its way out.
First drain your radiator. There is a petcock
drain on the lower,
passenger side of your radiator. It should have a rubber hose attached.
I found that a little duct tape to secure the hose straight against the
shroud makes it easier to drain it into a antifreeze bottle or
you look at the top of your
engine this is what you will see:
Not a lot of room at all between that fan shroud
and the pulleys. You
could possibly do the job with the fan shroud on, but I would HIGHLY
recommend that you remove it - it will make your life a lot easier.
Before you remove the fan shroud, you should
unbolt the fan clutch
and fan from the water pump pulley. If your water pump pulley does not
have any holes in it for a special tool, your best bet for removal is
probably the hammer and crescent wrench. With the pulley belt still on,
get a large crescent wrench and grip the large fan clutch nut. You will
need to hit it several times to knock it loose. The trick to finding
out which way the nut needs to turn is to watch which way the fan spins
while the engine is on. Hit the nut the same way the fan spun. My fan
spins counter-clockwise, thus, the nut broke loose by me hitting it
counter clockwise. Once you break the large nut loose, unthread it all
the way and set it down in the fan shroud.
To remove the fan
shroud, you must first remove 2 radiator hoses. The
top one is on the passenger side, just squeeze the clamps, pull it off
and bend it out of the way. The lower one is on the driver's side, do
Next, you will need to remove the 4 bolts
securing the fan shroud.
The picture below will indicate where they are located. Be sure to
unplug the plug from the shroud as well.
You may wonder how they even got the 4th bolt
screwed in during assembly, let alone how to get it back out. Some
people have said that a socket with a few extensions did the trick, but
with my WJ, there wasn't enough room between sheet metal and the bolt
to get a socket in there. I found just by sticking my hand through
lines and hoses and using a open ended wrench that I could slowly turn
it out. When putting them back in, I took one look at the situation
again, tested the shroud for secureness and then scrapped the 4th bolt.
I figured it would be OK without it.
Once you get the 4 bolts out, you will need to
work the fan shroud and fan, up and out the top of the engine
compartment. Doing this will create a VAST space for you to work in.
This is a picture of the engine once you get the
shroud and fan out of the way. Note, these pictures were taken on the
reassembly process, so the water pump is new and the blue rubber cap is
just to protect the new threads.
To get the old pump out, you will need to remove
the the small hose connected to the metal tube coming out the top of
the water pump. You can leave the intake hose on for right now and pull
it out with the water pump. Once you disconnect the small hose, remove
the 5 bolts that hold the water pump to the engine block. Be sure and
keep track which holes they went in as they may be different sizes. In
the picture below, you can see the old water pump, the pulley, and the
metal tube as well as the locations of the 5 bolts.
Once you get the 5 bolts removed, you may have
to gently tap the water pump itself with a mallet or hammer to get it
to break free from the old gasket. Be sure to have a pan below the
engine to catch coolant as more will poor out at this point.
When you have the old pump out, remove the
pulley's 4 bolts and set it aside for reassembly. Also, remove the
metal tube and set it aside as well. Examine it for corrosion and
possible replacement. Mine was in good shape so I reused it on the new
The next step I did was to remove and replace
the thermostat as well. This is optional, but since you have it all
apart, you might as well replace it since it's only a few bucks extra.
Remove the output tube as well as the small
rubber hose and disconnect the sensor from the thermostat housing.
There will be 2 bolts holding the housing on. Remove those and gently
tap the housing to break it free from the gasket. More coolant will
Be sure to
THOROUGHLY clean all surfaces where new gaskets will be
mated. Here is a picture of the thermostat housing after I cleaned its
At this point,
remove the thermostat (remember how it was positioned)
and clean all gasket material from the thermostat housing area as well
as the water pump. I used some degreaser and a exacto blade for the
gasket material. Be sure and clean it really well and use a rag to wipe
off any cleaner or coolant. Before installing new parts, make sure any
old gasket material that may have fallen into the engine channels is
Cleaned water pump
Once you have reached this point, it is pretty
much a matter of retracing your steps to install everything again.
Insert the new thermostat in the same position as the old one was and
reinstall the housing with the new gasket. Use a small amount of RTV
on the new gasket to hold it to the housing while mounting it. When
installing the water pump, use a small amount of RTV as well to hold
the new gasket to the new water pump. Also be sure to install the metal
tube before mounting the pump. I used some high-temp sealant on the
threads. According to the FSM, torque the bolts to 17 ft lbs for the I6
and 30 ft lbs for the 4.7L V8.
Place the fan shroud back in the engine
compartment with the fan inside just like removal. Thread the large nut
back on until snug and gently tap it with the large crescent wrench.
Don't try to force it tight, the engine turning the pulley will keep it
Reinstall the nuts to the shroud and all
and fill your radiator back up. Be sure to run your engine and purge
the air from the system as well.
That's about it, overall the process isn't to
hard. If you have any questions feel free to contact me.
Good luck on your replacment!