Coolant puddle

Coolant puddle directly under the water pump is nearly certain evidence that a water pump wants replacing. There are a few other things that could cause the same puddle. A loose or pin holed hose might.

Every water pump I have ever replaced acted similarly to what you are describe.

-sc

 

The motor has to be removed for this replacement.
Gary Bobileff

 

+1

 

I've replaced the water pump by dropping the fuel tank before. It's an unpleasant way to do it, but it was a preemptive warranty replacement (there were a bad batch of rebuilt WP's) a week after I pulled the motor for a major service.

I had little interest in pulling the motor a second time.

If the car is anywhere near it's timing belt interval, it will be worth while pulling the motor and doing it all at once.

I'm don't think it was any easier...just less parts and fluids to pull off and reinstall.

 

Fuel tank removal is nearly as much trouble and the brittle plastic fittings that need removing can be easily broken.

 

I think people are jumping the gun regarding WP and dropping the motor until a diagnosis is made. First drive the car and get the pressure up in the coolant system and see if you can see an active leak and possible source since you probably don't have a pressure tester. Get the car up in the air and take the pans off and look for drips. My process would be to pressurize the cooling system to about 20psi with cooling system pressure testor.
with tester you can work on a cold car and not cook yourself. I would have car in the air with pans off and look for drips. Sometimes you can see a drip and or crusting from the top coming from something as simple as hoses. They can be a pain to get to because often the intake manifold has to come off but it is easier than dropping a motor.

 

If you can get the car on a lift while it's running it is possible to see the water pump weep hole from below the left side of the engine, looking up.

 

+1 on R&R engine being the better way. I too have done fuel tank route for warranty work, total PIA and yes two of those clips on the breather lines broke!

If it drips after you stop and park it, 90% a water pump in my experiences. I have seen one where the pulley had slowly worn through that 'S' shaped hose too.

 

Or just look now while it's cold and on the ground --- if it has just dropped a puddle, there will likely be some evidence (a droplet or moisture) at the weep hole. Alternatively, if it is difficult to see directly, just grab a dry, clean kleenex and reach under the water pump and wipe ---- if it comes back with even a spot of wetness at all, the pump is leaking.

 

Good luck getting your hand in there.

 

Is it not at all reachable with belt covers, etc. on the 355 ??? I do not know.