Coolant leak on '86 300E, Is it the pump?
 

Greetings All,

Once again I am trying to fix the wifes new to her car and there seems to be coolant that runs down the side of the oil pan and onto the ground. I checked out the water pump pulley and there seems to be a lot of slack like the shaft or bearing or both are worn out. I don't physically see coolant coming from the pump but was wondering if the Germans designed their pumps like ours with a hole on the bottom of the front bearing housing so it drips when the pump is in need of replacement I can't see under the pump because of it's placement so if there's something else I am missing, let me know.

Thanks,

Charles

Yes the water pump has a weep hole. Do you see the water start dripping immediately after shutting down? Can you possibly get a small mirror down in the area to see if you can see a "coolant crust" build up around the weep hole, or even see the coolant dripping after shut down?

I'm not certain, but isn't your water pump on the left side of the engine at the lower front of the block? Maybe you could see the weep hole from underneath the car.

Can't see under pump
 

Greetings,

The pump on the 300E is belt driven to the left side of the block (from the back looking forward) and with the solid bracket of the power steering pump extruding under the water pump you can't see under the water pump even from the bottom.


Charles

Have fun doing this job. Plan on replacing the tensioner and shock along with the bypass hose on the water pump. You may take a stab at replacing the sealon the upper timing cover while your in there. The job may seem impossible at times especially getting the water pump mounting bolts out. I used strange combinations of tools to get the job done. I had problems with the all of the allen bolts. I ended up using allen sockets held in place by prying them in and turning the allen socket with the box end of a combination wrench. I congratulated myself on a job well done. I took time to detail the engine and replace gaskets and such. It it time consuming, and it may take more than a day at home for a weekend warrior.

I had the same symptoms when the water pump failed (this year) on my 93 300E.

I've since learned to do a lot of work myself, and I understand that it is a frustrating and time-consuming task, but is a DIY job.

I wasn't very sure of my skills then, so I gave the dealer $860 to do the work. You can save over $500 if you do it yourself...

Just wanted to make sure I was thinking correctly
 

Greetings and Thanks,

To all that have replied. I just wanted to make sure being as I can't see under the pump from any angle you approach it that there wasn't something else, hose, etc. that could possibly be causing the coolant leak. From a top side view of the water pump it shouldn't be to hard to remove, maybe the back bolt may give me a problem but compared to a Ford Aerostar van with 16 bolts to remove without removing the fan, clutch or radiator, with less than a few inches to work in, this should be a piece of cake. I can't image why I'd have to replace the engine shock mount, front cover seal, bypass hose etc. They all are pretty accessible from what I can see.


Thanks,

Charles

The other components mentioned can be replaced without waiting for the water pump to go south...it's just that it's so much EASIER to perform with all that is removed in performing the water pump replacement...minutes instead of hours...can ya dig?

Considering the age of your car, if those parts have not been replaced, they will require attention soon...so why not get it over with since you have to deal with the water pump fiasco anyway?

Just a tip...;)