1986 MB 560SEL water-pump replacement

[ironone396522]

I have a 1986 Mercedes-Benz 560SEL; I'm replacing the water pump and I cannot get the bolt on the bottom of the water pump to come from betwee the pump and the harmonic balancer. The slots in the balancer appear to be too shallow to help me get the bolt out. The bolt is unscrewed. Any help you can give me will be greatly appreciated, Thanks,

ironone396522

[Strife]

I did this on an 86 560SL, which is probably much the same in this area. Those slots MAY have worked on earlier cars, but I think that I'm fairly handy and I couldn't do this. I had to take the pulley off and then the balancer. This is not as scary as it sounds, although of course you have to loosen all of the belts. Then, there are six bolts inside the pulley, and then it comes off. The harmonic balancer then knocks off, after sitting with liquid wrench a while, and some back and forth careful knocking with a mallet. The balancer as I recall is keyed, and the pulley has deliberately irregular spacing on the bolts so that it can be installed only one way - make a note the orientaion as you remove it and make certain that you have all six bolts started before tightening as you put it back together.

A lot of people replace that bottom bolt with a stud and nut, because of the addtional PITA.

Hopefully you have the manual, the belts all require proper tensioning and the water pump is getting screwed into aluminum and using the proper torque with those is absolutely critical. I did everything right, and mine leaks around the gasket a little. I'm going to redo it in the next week or so with a water pump I polished up.

[fjack]

Agree with Strife, the harmonic balance wheel has to come off, I would also replace the front crank seal while you are there, cost of the seal is negligible compared to the effort of taking everything off again, ended up making a tool hold the crank stationary when removing the 27mm centre bolt, also made another to press in the new seal.