1997-2001 Honda CR250 – Water Pump Service And Repair

Mar 25, 2020

How To Service The Water Pump On Your 1997-2001 Honda CR250

What Are The Signs Of A Bad Water Pump?

Your water pump is located at the front of your crankcase on the right side. Right next to the oil level plug is a tiny opening.

The other side of this opening sits between the impeller shaft oil and coolant seals. If you can see oil, coolant, or both coming out of that opening, your water pump is no longer sealed and needs to be repaired.

You can change the gasket on your water pump without removing the right crankcase cover. But if you need to change the seals, bearing, or impeller, your right crankcase cover must be removed.

2 - Water Pump Weep Hole — Water Pump Weep Hole. Keep This Opening Clean So You Can See If Your Cooling System Is Compromised.

The Tools You Will Need Are

8mm socket
Socket Wrench
Inch-Pound Torque Wrench
Blind Bearing Puller
Socket For Oil Seal
Socket For Water Seal
Flat Head Screwdriver
Lithium Grease
Scraper
Dremel
Parts Cleaner
Shop Towels
Safety Glasses
Mallet
Small Pick

Pre-Service Notes

You can buy all the parts and tools you need through our partner links.
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Service pictures with captions follow the steps below.

Water Pump Removal

Start by draining your coolant and oil.
I recommend removing the water pump cover while it is still mounted because it might put up a fight.
A few taps with a mallet should release the gasket but DO NOT hit it very hard, or in the same spot repeatedly.
Remove the right crankcase cover, and keep the bolts organized because length and placement are critical.
Make sure to remove the shaft side washer from the case, and make sure the exhaust valve governor washer stayed in place.

3 - Drain The Coolant — Start by draining your coolant and oil.

4 - Remove The Water Pump Cover While It Is Still Mounted — I recommend removing the water pump cover while it is still mounted because it might put up a fight.

5 - Inside Of The Water Pump — Inside Of The Water Pump

6 - Remove Case Side Impeller Shaft Washer — Make sure to remove the shaft side washer from the case, and make sure the exhaust valve governor washer stayed in place.

7 - Make Sure Exhaust Valve Governor Washer Is Still There — Make Sure Exhaust Valve Governor Washer Is Still There

Clean And Inspect

Thoroughly clean the mating surfaces and housing first, for two reasons.

One, cleaning first will save you time and money in the long run if you find damage and need to replace or fix the housing.
Two, you can see if anything was damaged during service.

Water Pump Disassembly

Hold the impeller shaft with a box wrench, and loosen the impeller with an 8mm socket.
The impeller looks like it is secured with a hex nut, but the impeller is all one piece.
Remove the impeller and copper washer, followed by the impeller shaft.
Remove the coolant side seal with a flat screwdriver and a towel to protect the housing.
The oil side seal is behind the impeller shaft bearing, and the bearing needs to be pulled with a blind bearing puller.
Now, you could, theoretically, punch the bearing out from outside the cover with a drift, but I am NOT TELLING YOU TO DO THAT.
Fortunately, the impeller bearing is not a press fit and can be removed and installed easily.
Remove the oil side seal with a flat head screwdriver and a towel.
Thoroughly clean the seal bores, and the bearing bore.

8 - Loosen And Remove The Impeller — Remove the impeller and copper washer, followed by the impeller shaft.

9 - Remove The impeller Shaft — Remove The impeller Shaft

10 - Remove Old Coolant Seal With Screwdriver And Towel — Remove the coolant side seal with a flat screwdriver and a towel to protect the housing.

11 - The Oil Seal Is Behind The Bearing — The oil side seal is behind the impeller shaft bearing, and the bearing needs to be pulled with a blind bearing puller.

12 - Remove The Bearing With A Blind Bearing Puller — Remove The Bearing With A Blind Bearing Puller

13 - Remove The Oil Seal With A Screwdriver And Towel — Remove the oil side seal with a flat head screwdriver and a towel.

Assembly

Pack your new oil seal with lithium grease and install it with the open side facing up.
Use a socket of matching size, and drive the seal into the bore.
Place your new bearing squarely over the bore, and drive it into place with a socket that matches the OUTSIDE bearing race.
Drive your bearing until it bottoms out.
Pack the coolant side seal with lithium grease, and install it with the open side facing up.
The coolant seal is a different size, so you will need to use a different matching socket to drive the seal into the bore.
Apply grease to the impeller shaft, and carefully install it into the case in a twisting motion.
Install a NEW copper washer, followed by your impeller.
Hold the impeller shaft with a box wrench and torque to 106-inch pounds.

14 - Greas The Lip Of The Oil Seal With Lithium Grease — Pack your new oil seal with lithium grease and install it with the open side facing up.

15 - Install The Oil Seal With The Open Side Facing UP — Use a socket of matching size, and drive the seal into the bore.

16 - Place The Bearing Squarely Over The Bore — Place your new bearing squarely over the bore, and drive it into place with a socket that matches the OUTSIDE bearing race.

17 - Drive The Bearing With A Socket That Matches The OUTSIDE Bearing Race — Drive your bearing until it bottoms out.

18 - Grease And Install The Coolant Seal With The Opening Facing UP — Pack the coolant side seal with lithium grease, and install it with the open side facing up.

19 - Drive The Seal With A Matching Socket — The coolant seal is a different size, so you will need to use a different matching socket to drive the seal into the bore.

20 - Grease The Impeller Shaft — Apply grease to the impeller shaft, and carefully install it into the case in a twisting motion.

21 - Install The Impeller Shaft In A Twisting Motion — Install The Impeller Shaft In A Twisting Motion

22 - Install A NEW Copper Washer — Install a NEW copper washer, followed by your impeller.

23 - Install The Impeller — Install The Impeller

24 - Torque The Impeller To 106 Inch Pounds — Hold the impeller shaft with a box wrench and torque to 106-inch pounds.

Water Pump Installation

Place your new dowels in the case.
Place your inner gasket, followed by the flow plate, followed by the outer gasket.
Place your water pump cover and press it firmly into place.
Install the case side impeller shaft washer and make sure the exhaust valve governor washer is still in place.
Install a fresh gasket on your crankcase and install the right crankcase cover.
Place your bolts that you definitely kept organized and tighten them hand tight.
The right crankcase bolts do not have a torque specification, but the water pump cover does at 106-inch pounds.
However, I DO NOT recommend torquing these bolts to 106-inch pounds, as I have had several bolts break on me in the past.
I recommend tightening the right crankcase cover bolts no tighter than what a small 1/4in ratchet will achieve.