replaced water pump - now coolant leak under shifter

Long time lurker - first time poster!

My 2002, 540i 6speed has 99,984 miles (almost made it to 100,000). Yesterday my water pump bearing exploded and the serpentine belt disintegrated.

I put in a new h20 pump and belt. Everything is fine. Well almost....

When I turn on my heater (I get hot air), I see two puddles under my car. The drips come about every 3-5 seconds. When I have the A/C on cold no drips.

HELP!

Thanks,
Randy

It might be the heater hoses behind the intake manifold. If you haven't replaced those, they are cheap. The coolant is probably leaking onto the tranny then making its way down.

Originally Posted by SoCaLE39

It might be the heater hoses behind the intake manifold. If you haven't replaced those, they are cheap. The coolant is probably leaking onto the tranny then making its way down.

Maybe I damaged or dislodged them when removing the water pump? There are two going into the pump (input/output?). Perhaps when I pushed and pulled to get the metal pipes out of the pump, they were dislodged in the back where they connect to the hoses in some way?

Thanks again

Most likely the o-rings for the 2 pipes that run under the intake to the rear water manifold. Did the pipes come out when changing the pump? If they don't go back in very straight, the pipe can tear the o-ring.

Originally Posted by 02540ico

Most likely the o-rings for the 2 pipes that run under the intake to the rear water manifold. Did the pipes come out when changing the pump? If they don't go back in very straight, the pipe can tear the o-ring.

Does that mean I have to remove the manifold to get to those O rings (e.g., several hour job)?

Thanks,
Randy

Where are the puddles? Back of engine, side, front?

If it is the transfer pipes, I believe the intake plenum has to be removed to access the o-rings, also either the water pump, or rear water manifold.

Try to find the source of the leak before spending hours and $$ replacing parts.

Originally Posted by 02540ico

Where are the puddles? Back of engine, side, front?

If it is the transfer pipes, I believe the intake plenum has to be removed to access the o-rings, also either the water pump, or rear water manifold.

Try to find the source of the leak before spending hours and $$ replacing parts.

The puddles are underneath the back of the engine. I'm just a weekend do-it-yourselfer so I may have this wrong, but it looks like my tubular frame joins in a "Y" under my manual shifter. The water drops on two sides of the singular portion of the "Y"

Randy

Pop off the engine cover so you can get a better view of the back of the engine. You should be able to see if it's a heater hose, the valley pan, or the tube(s) from the water pump. You may have to use a mirror to see everything.
If you're only seeing the leak when the heater is on, I'd have to agree with SoCaLE39 on the heater hoses.

Originally Posted by 02540ico

Pop off the engine cover so you can get a better view of the back of the engine. You should be able to see if it's a heater hose, the valley pan, or the tube(s) from the water pump. You may have to use a mirror to see everything.
If you're only seeing the leak when the heater is on, I'd have to agree with SoCaLE39 on the heater hoses.

Interestingly, my leaks have stopped! (Yes I still have coolant Can't explain it, with the heater on full blast everything is dry as a bone and I didn't change a thing.

I was able to see the heater hoses by taking off the engine cover and using a mirror. They are all dry with everything running.

Maybe bleeding the system helped? Anyway, for now, I think I am good. Thanks to all on the forum for the help.

Randy