ROADSTIR

I am going to try and chnge my water pumps, pulley, tensioner, belt on my 2005 CDI.

1. is OEM pump worth the premium price?
2. if not, then is GMB or Beck Arnley any good?
3. Where's the best and cheapest place to buy these goods?

Thanks!

Tschuss_Bill

I'll be doing the same repair in the next month or so along with the all important thermostat.

I have not found a single source for all bits.

ECStuning has graf waterpump (with gaskets), belt tensioner, MB antifreeze.

Rocky Mountain European for Wahler Thermostat and Contitech belt

Other needed parts include, idler pulley and female torx sockets.

edwinwalke

Try Parts.com They have OEM MB parts and very competitive prices. I have used them and have had good results.

dspencer

I just did my water pump today. I got a Gates belt and a Graf water pump and 2 pulleys from them.

Its an easier job to do than I was guessing. It took a about three hours of steady work to do it.

The only thing I had a problem with was the Graf pump. The housing has one hole that should have been threaded but was not.

ROADSTIR

dspencer,

How much experience have you had doing your own work? I've got a compressor and air tools an a decent toolbox. Have replaced the ball joints on mine and it wasn't too bad, but I don't want to get it torn apart and then get hung out to dry. I want to replace the pulley, and belt tensioner, too. Do those need to be removed in the course of putting in the pump? If not, are they a big deal to R&R? Finally, how big a deal was it to remove the sound dampening panels?

Thanks for the advice!

dspencer

I used to do just about anything that was not heavy duty. Now being older and slower I like to have a guy I know who's good at this do mine but he's been busy this week.

The water pump is easy though.
T60 and T50 Torx wrench.
E12 and E10 star sockets.
10mm socket.
A small screwdriver is all you'll need.

I did go by and get a couple gallons of Mercedes antifreeze.
I got this from another thread. I'll repost it here. One for the removal of the radiator shroud/serpentine belt and the other for the water pump.

http://www.benzworld.org/forums/atta...ntine-belt.pdf
http://www.benzworld.org/forums/atta...eplacement.pdf

Make sure you take off that intake accordion duct on the left side(facing from the front) of the radiator. I left off that and it took me 5 minutes to figure out that it would not come out if I left that step out.
Make sure you cover the alternator good if you don't drain your system first.

All the parts come off easily or I should say they did on mine. The pulleys are just like taking off a bolt after you take the dust covers off.
I did mine from the top and did not have to mess with the sound dampening at all.

I got all my parts from Auto Parts Warehouse (autopartswarehouse.com)

ROADSTIR

dspencer, you are a wealth of information! Thanks much for the help. I've ordered my parts and will have at it soon.

David

ROADSTIR

Ok, am tackling the following in a few minutes-

water pump
belt tensioner
idler pulley
belt
thermostat

I saw that the water pump does not take any sealant like Permatex, but does the thermostat? (Mine came as a unit with the housing, too)

Also, I have T 50 & T60 sockets. But you call for the wrenches. Any difference?

Thanks for the pdf's on the water pump and belt. Any out there on the thermostat replacement?

Thanks for all the help,

David

ROADSTIR

THAT certainly went well. I didn't convert the cheap torque wrench units into NM and stripped two bolts putting the pump back on. And Bill, my unit also came with an uptapped hole for one of the pulleys. BP is rising fast.

After thinking about this last night I had a thought. The very ends of the 3 screws are what had the threads stripped off. Does that mean that the block itself is not stripped, just the screws? if so, can I just blow out the hole with air and put a new screw properly torqued back in the hole?

Also, how do I fix the unthreaded hole in the new water pump? One of the big screw holes, like another poster experienced, came untapped. Does it need to be taken to a machine shop or can I buy a tap & die kit and do it?

Thanks for all the help~

dspencer

The unthreaded hole is the one that is the bottom hole in the brace that takes 3 screws to hold it in. I put the screw on the socket and started it, making sure it was going straight on.
It took and tightened up without having to go find a tap which probably would have been better. Taps are pretty cheap.

If you'll take one of the screws to a hardware store you can probably find a tap for the holes that stripped. If that does not work you could probably go to the next larger size tap or install a heli-coil to repair the hole. I've gone to the next larger size bolt before and it works just fine.




David

FWhite

On any of the replacement Mercedes parts that have untapped holes in aluminum you need to use the original bolt and just screw it in. The original bolts you may notice are not round. This is to reduce friction. They are designed to form a thread as they are screwed in. The thread that is produced is stronger than a tapped thread due to the cold working of the material.

The untapped hole is also larger than a hole that is designed for tapping to allow for the displaced metal to flow. The resulting thread has the correct minor diameter even though the starting hole was oversize. Simply running a tap into the hole results in a weak thread with an oversize minor diameter. If you insist on tapping the holes before assembly at least use a proper thread forming tap instead of a conventional cut tap. You have to get these from an industrial supply house. The local parts store wont have these. I hope I haven't bored you to tears.

ROADSTIR

Spencer and White- your advice is much appreciated.

After a week of having my car down I threw up the white flag. I went to NAPA and the guy was great. He took the pump in the back and tapped it in 5 minutes and told me to have a nice day! I considered Heli Coil'ing the 3 stripped ones, but was just gassed.

To me , the ultimate embarassment is having to take your car back to your mechanic after you fail to fix it on your own. This experience was worse- they originally told me that they would install my water pump for $250, and would charge me for any extra time spent installing the extra parts (thermo, tensioner, pulleys). When I called and told them I surrender, they told me they weren't comfortable fixing the stripped holes and to take it to another shop they recommended. After a $60 tow (2 miles) the shop said they'd call me that afternoon after they had time to look at it. He said they'd do the Heli Coils for time & material. Ok, I think. Yesterday at 5:00 I get a call and he said they were all done except for adding the coolant and that I could pick it up on Monday.

Apparently, they just did the work without calling me with the estimate, as promised. (Keep in mind I'd already torn it down and had all the new parts) He said the bill was $675 for the 3 Heli Coils and reassembling everything. Will someone tell me if this is reasonable? I brought it in at lunch and am sure they didn't look at it until early to mid afternoon. Could "time & materials" really add up to $675 in those few hours or could the materials really be that much. Ouch!