Help with Water Pump Installation

I need to replace the water pump in my 1978 280CE, but I'm not totally clear on how to do it. I have the part I need, but I don't have a manual available to me, and I'm really not experienced whatsoever when
it comes to maintaining cars. If anyone in this group has done this in the past and could provide me with a step-by-step guide through the repair, it would be much apprecited. Failing that, I've been quoted about $270 CDN to have it done for me by a local mechanic, who thinks it will take about three hours in work. Is this a reasonable amount to expect? Cheers.
Rowan Smith
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Drain the coolant; remove the fan and shroud; loosen the drive belts; remove the crankshaft pulley and damper by removing the six attaching screws (leave the hub in place on the crankshaft). Remove the five screws holding the water pump to its housing, and strike the water pump sideways to loosen it. Clean the gasket surface of the housing thoroughly with a razor blade.
Reverse to assemble.
Bill Ditmire Ditmire Motorworks,Inc. 425 White Horse Pike Absecon,NJ 08201 http://www.ditmire.com 609-641-3392
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
I've done this one. The new "water pump" in your hand is the insert which bolts into the water pump's housing. The only thing that's really new is its bearing and seal. So that you'll appreciate your mechanic's offer I'll describe the job.
You'll need some metric sockets, a short 4" or 6" extension, ratchet and open end and closed end wrenches. If you lack these and feel that they are "instruments of the devil" have the mechanic do the job. QED
The water pump is located on the front of the engine, behind the belt driven fan. The coolant must be drained into a pan; the drain plug is on the bottom of the radiator, on the left. You get to it by lying under the front bumper. If the coolant hasn't been replaced in years it should be.
The drive belt's tension needs to be slackened; that's done at the alternator. Its mounting bolts need to be loosened (only) so the adjustment screw can move inward to relax the belt. You'll be plenty dirty after this.
Remove the top radiator hose from the thermostat (water pump end) (only) and gently stuff it somewhere out of the way. Now comes the tough part.
There are four or five small bolts on the front of the belt driven fan hub that need to be removed. The work space between the radiator core and bolts is tight and the bolts are tight. Some people remove the radiator. IT'S VERY EASY TO ROUND THE HEADS so be absolutely sure your closed end wrench is the exact size and fits perfectly. If you round one of them the job is lost to the mechanic after a tow to his shop. Remove the fan and hub; stand the fan vertically - don't lay it down. Now it's time for the water pump.
Your car's engine has a large harmonic vibration damper with a cut out portion that you need, so rotate the engine with the key or your hands so its cut out allows your socket access to the water pump's lower bolts. Use a socket to remove the five or six bolts that secure the rotating core from its housing. Remove the core and scrape the gasket surface of the housing clean so the new gasket will seat and not leak. Install the "new" pump with the gasket in place; the pump mounts only one way or the bolts won't fit so that's easy. Torque the bolts to about 20 ft lbs.
Reinstall the fan hub and fan, tighten the new hub bolts with a closed end wrench as tight as your hands can stand. Reinstall the drive belt and tension it at the alternator, secure the alternator's mounting bolts. Reattach the upper radiator hose to the thermostat end. Replace the radiator's drain plug and refill the coolant.
This is the job. It's not mentally difficult but has a few nasty bits. IMHO your mechanic is earning his $270 for it requires tools and takes at least two, if not three hours to complete. And remember, he has to deal with any rounded bolts etc. I found the bent over position of the job gave me a sore back for the next two days.
Happy New Year
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Motorsforum.com is a website by car enthusiasts for car enthusiasts. It is not affiliated with any of the car or spare part manufacturers or car dealers discussed here. All logos and trade names are the property of their respective owners.