Hello All
My sel is leaking water down the driver's side of the engine...assuming it is water pump. I talked to my mechanic and he said 1000.00 to do. Just wondering is he in line. he said I would spend alot in special tools and the pump is 400.00. I have read on the pump and know it is tough but can it be done DIY?

Thanks
Warren

Yow, that sounds WAY too much in my opinion... I would check around. Also could be something else - possibly the head gasket, but I am not sure... I think these leak toward the back of the engine?

I would wait for more info/advice here before making that $1000 plunge!

$1K sounds kinda high...I recently had mine replaced cause the bearing was getting real loud...part cost $185...labor $150...done at my local independent shop.

Lead
1991 300SE (W126)

The pump should only be about $200. I agree it is a serious job and there is a special tool that can aid the process, but is not absolutely necessary. I don't own one of the tools and I have changed one before.

I believe that he's soaking you. Call the dealer and see what they get. They might indeed get $1,000, but that is to be expected from a dealer, not from an independent.

My $0.02,
Larry

Replacing a water pump on a M103 is a long process - if you haven't done it before. If you have any mechanical bent it can be done without special tools other than long thin extensions for your sockets to undo the water pump bolts.

You need to remove a fair bit of individual components to get at the pump. Allow 6 -8 hours to do the job by yourself for the first time.
The job is fairly logical and methodical. You need a new pump, all radiator hoses plus new clamps, thermostat and sepentine belt. (don't screw with old radiator hoses and clamps).
Get new coolant - correct stuff for 103 engines.

What I remove to do the job.
Fan and clutch.
Fan, water pump and power steering pulleys.
Sepentine belt, tensioner and belt adjuster.
Undo bolts for power steering pump assembly and move aside.
Heater tube running across front of engine into water pump. You get a new O ring for this in the water pump kit).
I remove the oil dipstick tube and first and second injector to get at the top right bolt of the water pump (Others don't do this - depends on how much room you have)
I also remove the distributor for easier access.
here is a image of everything removed.

I think 6 to 8 hours is an overestimation, but maybe that much for an inexperienced do it yourselfer. Certainly for a tech making his living working on these cars, if it takes him 6 or more hours, he's in the wrong line of work IMHO.

It took me 6 hours to do the one on my M103 at a relaxed pace, and I had never done one before. I imagine an experienced pro could probably do one in about 3 or 4 hours.

__________________
08 W251 R350
97 W210 E320
91 W124 300E
86 W126 560SEL
85 W126 380SE Silver
85 W126 380SE Cranberry
79 W123 250
78 W123 280E
75 W114 280

Allow 6 -8 hours to do the job by yourself for the first time.

Experienced professionals shouldn't need to remove all those components either.

$1000 seems pretty high even for California. I had an indy replace the pump in my 300e about two years ago and I think it cost me about $600 parts and labor. I would have done the job myself except that it was winter and I would have had to work out in the driveway in the rain.

I did research the job and I agree that a decent DIY owner could do it with some study on how to proceed. Lots of things need to be moved out of the way.

I wasn't too pleased with the job my indy did. He apparently assigned it to a young mechanic in the shop who was a bit careless. The tensioner was reinstalled with the pointer out of sight and one of the bolts holding the power steering pump on was never tightened. The noisy bearing sound has gone though.

__________________
1986 300E
1993 Volvo 940 Wagon
1984 Volvo 240 (daughter's)
1976 Dodge 1/2T pickup, gas hog

Thanks for all the imput and the pic is great! There are so many opinions and options. I am concerned that a shop might delegate this job off to a lesser experienced mech as 300Holst mentioned. I can do better on my own. The tensioner makes me nervous tho, it just looks tricky

I assume you have made sure that it's not a loose hose clamp or the heater tube O-ring?

__________________
-tp


1990 300SE "Corinne"- 145k daily driver - street modified differential - PARTING OUT OR SELLING SOON - PORTLAND OR. AREA - PM ME FOR DETAILS
1988 560SEL "Gunther"- 190K passes anything except a gas station
1997 S420 - 265k just bought it with a rebuilt trans. Lovely condition

as far as I can tell no..hard to see anything with or without dentist mirror. It is leaking below pump, by block and running down to the driver side of oil pan 1/4 back from front of pan...it has gotten worse now...Price of pump is all over the place...Which pump is the best?

The trick to the tensioner is making sure you undo the 19mm bolt that fastens the tensioner up first. There is a tensioner adjuster with a large 13mm bolt on top. Don't move this until loosening the 19mm bolt.

This job is logical and straight forward. It just takes time. Use a digital camera as you go to record your progress.

If you do it wrong this could happen


here is a picture of some of the components to remove the tensioner. Note that the pulleys are still on in the image - these must come off.

Book time according to Chilton labor guide is 6.2 hrs.

__________________
1993 400E


Mercedes Benz technician since 1982

ASE Master technician to 12/2015

Here is what happens.



I have a Chinese made ASA water puimp. Cost me $ 60.00. I'm not happy with it. I may change it out for an OEM. The pulleys don't exactly line up properly and the serpentine belt is squeaking.