PeachParts Mercedes-Benz Forum - View Single Post - Arrrgh! Auxilliary coolant pump leaking.....

rwthomas1 · #9 04-02-2003, 01:27 AM

Heres what I did:
Purchased a used aux. pump at local yard. Yanked it out of an 82SD, couldn't pass it up for $5. Installed "new" pump. I grabbed the connector from the SD as well. I wired in a 15amp relay which is latched by the factory pump feed. Inline fuse just in case. Also 10amp inline fuse on the new hot from the relay to the pump. I left the pump ground hooked up the original way. By taking the connector from the SD and cutting the other connector off my bad pump I was able to make a wiring harness that simply plugs into the factory setup. This way I didn't have to cut any wires on the car. I do have a question though:

I installed a 1.25amp/250volt "fast acting" fuse in the factory pump feed that now latches the relay. It blew on the test drive. I know nothing about fuses. I don't think the "bosch" relays pull more than 100milliamps so I should be fine???? I put a 5amp in to test and all is working fine. What should I try? I am thinking a 1.5amp slo-blow fuse? How do you test for amp load on the relay?

FredmBurgess, I know you just shipped me a dead pump and yes I still want it. I plan on doing a rebuild and having a spare. Thanks again, RT