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96 C220 Water Pump Question

13K views 12 replies 8 participants last post by  djaydave 
#1 ·
I search the forum first but could not find an answer to this. Can someone tell me waht the signs are of a leaking water pump. Theres some wetness on the face of the pump pump but no real sign of water on the floor. I'm also slightly loosing coolant. Checked all hose fittings and all look tight and no signs of leak thru them. Thanks
 
#3 ·
From what you described (plus a slight rise in engine temp particularly while sitting) my guess is that you need a new pump. What's the mileage on the car? I had to replace mine (96 C220) at about 122k miles and I understand that it's somewhat typical for this model at that mileage. Probably good to replace the thermostat at the same time.
 
#5 ·
Thanks all for the responses. I got 307k. I don't know if its been replaced before. I got it with 250k.

Looking at the job, it seems pretty straight-forward....
-remove belt
-remove shroud, fan and clutch
-remove water pump

Does that look like it?
 
#4 ·
When the w/p starts to wear there may be some leakage as you describe from the bearing starting to fail, upon further failure the coolant will leak out the weep hole at the bottom of the pump but not necessarily in that order. Usually the leaking water will actually burn off some of the dirt on the engine around that area exposing metal surfaces.
Do yourself a favor, get a new pump, thermostat, and flush the system. If not you may find yourself far away from home with a completely failed water pump. B
 
#6 · (Edited)
Ok, replace water pump this afternoon. Wasn't too bad of a job.

Here's what i did.....

- Got spanner wrench from AZ (part no 27018). see pictures. Use AZ wrench tool to remove fan clutch off water pump pulley. AZ rents them for $25 deposit refundable if returned in 90 days.
- Loosen fan nut using the small 36 mm and 47 mm spanner wrench (see picture on how the large wrench is used). Nut is unscrewed in clockwise direction. Fully uncrew fan nut and lift up and remove.
- After removing fan, remove Fan shroud. After removing fan shroud, you will now notice you have lots of room to work on the pump.
- Remove fan belt (turn tensioner CCW) to remove belt.
- Remove fan pulley by loosening the 4 - 5mm allen-head screws. Use the large spanner wrench to hold the pulley down while loosening each screw. Be careful when turning each allen screw. Allen wrench must be seated securely on the allen screw head when turning (I kinda messed up one of the aallen screw heads. Turned out Home Depot had them (M6 X 12mm) so I replace them all. Also used tension washers rather than flat ones.
- Loosen and remove all 4 screws of pulley and remove pulley. Keep all screws in secure place .
- Removing the pulley exposes the front of the water pump.
- Before removing the water pump, I cleaned the front of the engine by spraying degreaser all over the front of the engine and pressure washed it. After cleaning the engine, using a Sharpie, I marked each water pump bolt so I remember which bolt-hole to return them to. They are different lengths so its important to do this. The pump is hel by 8 hex bolts (2-13mm & 6-10mm).
- I proceeded to loosen and remove all bolts and pulled the pump and gasket out.
- Detached hoses off the pump. You can do this either before or after pulling the pump.
- Reversing the procedure, I installed the new pump.





 
#7 ·
Your Instructions for the water pump replacement came in real handy, my 96 C220 had a catastrophic water pump failure, I notice fluid under the vehicle and coolant leaking thru the weep hole. I got exactly the same part from AZ. but it would not fit, my viscuous fan nut and pulley is slightly different , just as the Hanes book said might be possible, I got instead a Kragen's Ford Fan clutch wrench for $20, exact fit. Took less than 2 hours not counting driving back to Kragen to trade my core, reman is $140.
 
#9 ·
Found Cause of Leak

It looks like my WP was fine but I guess it was good exercise to replace it.

I should have thought of using a coolant pressure tester tool first before changing any parts. Using this tool (rented from AZ), the leak showed up at the heater hose connector pipe located near the fire wall just to the left of the brake booster.

That bugger was tough to get to to replace. I tested it again after I replaced it and no more leak.

Advice: Try using a coolant pressure tool first to find coolant leak.
 
#12 ·
That means its working properly according to what I have been told. That is the secondary air pump for emissions (also called smog pump). Mine does not work anymore. Its suppose to sound like a vacuum cleaner when first started and fades.
 
#13 ·
im now in this situation, my water pump is noisey....somehow is loose and now my ''belt'' comes off. (1996 c220 443 000 - yup u read right).
being in Canada Kitchener - Ontario, what brand and where do i get one of these Water Pumps ?
 
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