Coolant leak / water pump questions

[berickson926]

I used a loaner pressure tester to do a 15psi check and bleeding of the system. System slowly loses pressure over time.

After several rounds of bleeding I finally noticed a coolant leak coming off the bottom of the water pump, drivers side.


I've had overheating issues in the past and have still been trying to sort everything out. Things I've done so far:

Replaced radiator (and the flexible hoses immediately connecting to it)
Replaced otterstat
Replaced fan/fan fail relays with bitsyncmaster's upgrades.
Replaced fan CB and repaired corroded wire connection to CB.
Had DMC CA replace all the flexible coolant hoses under the intake.
Installed the auto bleeder kit.

System generally does a poor job cooling itself - just idling it can take 3-4 minutes or more for the car to cool down enough for fans to turn off. Maybe that is okay? I'm not really sure. It can still run hot when driven in reverse or while navigating parking spots in a parking lot.

I was still trying to figure out how air was getting into the system (worried about head gasket failure, to be honest) aside from me doing a poor job bleeding the car. Then I finally noticed this leak under the water pump.


I've also read there is a weep hole that can leak, but not really sure what solution there is when this happens. Am I looking at a water pump replacement?



I took a few pictures looking down on the engine but they aren't too useful. I will go back underneath the car to see if I can get a better shot.

[DMC-81]

Hi there,

My understanding is that if the water pump leaks through that weep hole, it has or is beginning to fail.

Best of luck with your diagnosis and repair. I am in the middle of an engine refresh including a pump replacement, and this forum and a workshop manual are valuable.

[Jonathan]

System generally does a poor job cooling itself - just idling it can take 3-4 minutes or more for the car to cool down enough for fans to turn off. Maybe that is okay? I'm not really sure. It can still run hot when driven in reverse or while navigating parking spots in a parking lot.

Believe it or not, the system does cool the car well, but your example has the logic for why a bit backwards. The car's cooling system will keep the car cool enough often without the fans running when you are out cruising around at highway speeds. Depending on the ambient temperature that day for where you are of course. The air flow of the car moving and going in the front and past the coolant going through the radiator is often sufficient. It can have a harder time staying cool or longer fan running duration, as you noted, when sitting idle. Not because of high RPMs creating more heat, but because at the low RPMs when idling, you aren't moving. You follow?

I used a loaner pressure tester to do a 15psi check and bleeding of the system. System slowly loses pressure over time.

After several rounds of bleeding I finally noticed a coolant leak coming off the bottom of the water pump, drivers side.

I've had overheating issues in the past and have still been trying to sort everything out. Things I've done so far:

Replaced radiator (and the flexible hoses immediately connecting to it)
Replaced otterstat
Replaced fan/fan fail relays with bitsyncmaster's upgrades.
Replaced fan CB and repaired corroded wire connection to CB.
Had DMC CA replace all the flexible coolant hoses under the intake.
Installed the auto bleeder kit.

I was still trying to figure out how air was getting into the system (worried about head gasket failure, to be honest) aside from me doing a poor job bleeding the car. Then I finally noticed this leak under the water pump.

I've also read there is a weep hole that can leak, but not really sure what solution there is when this happens. Am I looking at a water pump replacement?

You list most of the main things to go wrong or need replacing. You might have been fighting more than one cause, or you might have replaced more than the thing that was causing the problem.

I can't tell you much about water pump replacements or weep holes as I haven't replaced mine, but once you get that sorted out, go back to basics and make sure the air is bled out first and then ensure the fans are coming on via otterstat jumper and/or A/C clutch engaged. Confirm the fans are blowing a decent amount of air and making lots of noise and then continue with troubleshooting. No air in the system and fans coming on when they should will generally solve the majority of problems.

[berickson926]

Thanks for the feedback!

Here are some pictures, but it is still a little hard to see.

Attachment 33956Attachment 33957Attachment 33958Attachment 33959

[DMC-81]

I'd verify the exact location of the leak. Is it coming from the weep hole, or from below the pump (from the engine valley). As you stated, you had some hoses replaced under the intake, so you will want to ensure those hoses are not leaking from a loose clamp. Do you know how old your pump is?

[berickson926]

Unfortunately I don't know how old the pump is, and have only owned this car for about a little less than a year.

I'm not really sure how to get in there for a better picture without taking the intake off.

I'm also not even really sure what this weep hole looks like, most diagrams don't seem to show the pump from the back/bottom.

[SS Spoiler]

DMC 81 is right....I ended up replacing a pump when all it was a loose clamp....grrrr

[kings1527]

An outstanding recommendation from Dave Swingle in a different thread:

-Try jacking your car from the front and seeing if the leak becomes greater when you lift the car and tilt it back towards the water pump. If you get an immediate flow from doing that, then you have coolant in the valley and very possibly have a clamp/hose issue under the manifold. If the leak doesn't get worse when you lift the car, it's something else.-

[DMC-81]

Here's a picture of a new and an old water pump bottom. I have pointed to the hole with a pen....

image.jpg

[David T]

If you go under the car and look up at the nose of the water pump (behind the pulley) you will see the weep hole. If you see moisture or even just staining, it is leaking and it should not leak at all. To replace the water pump the intake manifold has to come off again. Bottom line, if you have ANY leaks eventually you will lose enough coolant so that air will get into the system and once that happens the car will overheat.