Fan clutch work...replace water pump while I'm in there? - PeachParts Mercedes-Benz Forum

RavenTBK · #1 07-24-2014, 09:55 PM

Yep. The topic is pretty much it.

The banana boat was in the shop recently getting the ROLLGUY conversion kit installed and charged up. The mech pointed out to me that my fan was siezed. I figured he was referring to the aux fan, but then saw my mechanical fan was 100% engaged all the time. Basically, the clutch failed in the locked position.

That explains why my MPGs have always hovered around 20, even with granny style driving. I never bothered to check, and assumed it was a solid mount (clutchless) fan like on the older 617. Without a cooling problem, why mess with it? duhh..

Anyway, feeling emboldened by other threads of folks successfully running without a fan, I went out and removed the bugger from the water pump pulley. The past 24 hours has been wonderful. Its like the car gained 20hp. I have had no real issues with temperature, as my commute occurs both early and late way outside of the rest of the world. Waiting in a Taco Smell drive through last night, she crept up to 100C, but dropped back to 85 within the first 1/4 mile of movement.

Now, this is not intended to be a permanent solution, as I do live in the hotter part of Florida, I kinda need the fan to keep crap in check. I considered going electric, but cost vs benefit pushes me back to mechanical.

I have already ordered a new Behr clutch, but I was wondering, how bad/good are the water pumps? While "I'm in there", would it be prudent to go on and replace it? Or is it easy enough to replace to do it later when it actually begins to fail? I havent seen too many threads with up/down votes on it. The one on my banana boat is either original, or dealer serviced like everything else on the car. I'm assuming the pumps rarely fail. How naive am I?

mannys9130 · #2 07-24-2014, 10:05 PM

They are pretty good. I consider the life of a water pump to be around 75-100k miles. Newer cars with timing belt driven water pumps should be replaced every 60k when the new belt kit is installed.

My sister's 85 190D started leaking from the weep hole shortly after we got it. It had been sitting, and I'm sure the push back into service didn't make the water pump seal very happy. It is very easy to replace on the 60X engines.

At the time, a Graff pump was 50 bucks. If I had the front of my motor taken apart, I would probably toss a new one on there just because. These cars generally suffer from failing OE parts from decades ago. The pump that came off my sister's car was OE stamped West Germany.

160k miles and almost 30 years is an outstanding life for a water pump in my opinion.

Marshall Welch · #3 07-24-2014, 11:52 PM

The water pump in my 82 300D-T failed a few years ago, at about 90K miles. It's kind of a headache when that happens.

I'm usually "if it isn't broke, don't fix it", but in this case, I'd strongly consider replacing it. The labor/time involved doing a replacement at a separate time probably makes it worthwhile to do it now.

From what I've learned here, Laso, Graf, and Genuine MB are the brands to stick with. I replaced mine with a Laso.

Mxfrank · #4 07-25-2014, 07:22 AM

My 190DT still has it's original pump. It has 334K miles on it. I've have a spare on the shelf for the last few years, waiting for the day. But it never seems to come. I wouldn't bother.

eatont9999 · #5 07-25-2014, 01:12 PM

I replaced my pump mainly because I needed to replace the water pump housing gasket and the pump needed to come off anyway. Someone used RTV to seal it to the housing, so I knew it was not original and someone had monkeyed around in there. I figured it was good insurance not knowing the make of the PO's replacement pump. If you take the route of removing the fan pulley (necessitating the release of the alternator belts), I would replace it just so I know I don't have to mess with that silly alternator tensioner again.

Zacharias · #6 07-25-2014, 01:22 PM

If the pump is of unknown vintage and looks tired (though don't they all, after even six months), it wouldn't be the worst idea.

However, get advice on good brands (price is not an absolute indicator, based on other threads).

My only comment would be that it isn't an awful job unless some monkey torqued down your alternator bolts like his life depended on it, as happened with me. Three-plus hours in 90 degree heat just to loosen the alternator.

eatont9999 · #7 07-25-2014, 01:32 PM

Quote:

Originally Posted by Zacharias

If the pump is of unknown vintage and looks tired (though don't they all, after even six months), it wouldn't be the worst idea.

However, get advice on good brands (price is not an absolute indicator, based on other threads).

My only comment would be that it isn't an awful job unless some monkey torqued down your alternator bolts like his life depended on it, as happened with me. Three-plus hours in 90 degree heat just to loosen the alternator.

I wound up with a broken alternator tensioner during an ice storm. That was fun! I had to steal the one off the 300SD I am restoring to get the other SD running. After that, I had to go to PNP in the middle if winter to snag another bolt. Luckily, it does not get very cold in DFW but still not fun.

disqo · #8 01-05-2015, 12:00 PM

I am about to replace my water pump. The manufacturer recommends no sealant on the gasket. Does anyone have any advice or experience otherwise?

vstech · #9 01-05-2015, 12:31 PM

I used no sealant on my graff wp on the 190... seals fine. no residue on the original gasket...

the new wp's have a ridge to facilitate fan clutch removal with a simple allen key, instead of a pulley grip tool...

eatont9999 · #10 01-05-2015, 01:13 PM

Quote:

Originally Posted by disqo

I am about to replace my water pump. The manufacturer recommends no sealant on the gasket. Does anyone have any advice or experience otherwise?

Clean both mating surfaces well and use only the correct paper gasket. Don't rely on the one that comes with the pump as it was much thicker with the pump I received.

The Gears · #11 01-05-2015, 02:18 PM

All I have ever used is a little light grease on each side if the paper gasket.
Keeps it from sticking to either the pump or block.
If the pump comes with a very thick gasket, that is some times required to accomidate a bit longer shaft or an impeller not pressed on all the way.

You can rig up a temp switch to kick on the electric AC fan at 100 C. That will save the day when in the food line up or traffic. I ran my 300D without a fan for many years with this set up. Don't go for a 90 C switch, the fan will be on all most of the time.

funola · #12 01-05-2015, 02:45 PM

Quote:

Originally Posted by The Gears

All I have ever used is a little light grease on each side if the paper gasket.
Keeps it from sticking to either the pump or block.
If the pump comes with a very thick gasket, that is some times required to accomidate a bit longer shaft or an impeller not pressed on all the way.

You can rig up a temp switch to kick on the electric AC fan at 100 C. That will save the day when in the food line up or traffic. I ran my 300D without a fan for many years with this set up. Don't go for a 90 C switch, the fan will be on all most of the time.

Is there a suitable temp switch on the engine somewhere to automatically run the AC fan (via a relay)? I want to remove the clutch fan to see if it improves my MPG on my 85 which has been 20 mpg city. I think it should do better than that.