How do you replace the water pump on a 1998 Ford Ranger?
Buy a Chilton Manual or similar repair manual at your auto shop. There is no better way to describe what you have to do. It is a series of steps and there are pictures to guide you.
Just finished the job. not too bad. Here is what to do:
Disconnect neg terminal
remove air filter plenem
Remove clutch fan. On my fan guard "R.H Thread for clutch fan" was written
Rent the tool from advance auto for free. Makes this part of the job very easy
remove the fan guard ( 2 bolts) take the fan guard and clutch fan out of the engine compartment. Makes alot more room
remove serpentine belt ( 3/8 ratchet in belt tensioner)
remove water pump pully ( 4 bolts) have to hand hold "pully" to remove bolts
remove lower radiator hose and heater hose
remove water pump ( 12 bolts!!!)
Clean off old gasket material !!!!
Install in reverse order! tighten bolts from inside to outside on water pump
about 2 hours.
On the other hand...
Forget about the manuals. I have both Chilton and Haynes. For this procedure, they are less than useless, at least for a 2.5L 4-cyl. They don't say much more than the above. HERE'S THE STRAIGHT SCOOP:
Getting the Radiator, fan and pulley off is a piece of cake. What isn't mentioned is that to pull the pump off you have to remove the timing belt cover, and to do that, you have to remove the engine bracket holding the A/C compressor and the power steering pump, because the idler pulley is in the way, and too close to the cover to remove otherwise, and there are NO instructions for removing the bracket. (you should read some the the frustration in the Ford forums!) and then the inner belt cover, which requires the removal of the timing belt, and the misalignment risk that goes with that. By the way...the water pump on a 2.5 only has 3 bolts.
The pump is stuck onto a hidden down-tube with an o-ring. The plastic tube is a "Y" that goes to the lower radiator hose and the heater core. The pump just pulls off, but it's almost impossible to jam back on because of the angle. (Don't break this tube! It's a dealer-only S.O. part. How do you think I know this?) You can't get to this tube without removing the alternator!
MY ADVISE...JUST FORK OVER $300 TO A GOOD SHOP AND FORGET ABOUT TRYING TO DO IT YOURSELF!
The only 1998 Ford Ranger that has a cam belt is the 2.5 L In-line 4 cylinder. All other engines have a cam chain. Ford recommends to inspect the belt at 120,000 miles an replace as necessary. This is not an interference engine, so if the belt breaks no engine damage will occur. Cost really does no matter, as if it is worn out or needs replacing, you have not choice but to replace it.