Baetke

There is a small vent in the water pump housing located just above the index plate for the ignition timing. Kind of up and behind the two electrical connectors going temperature sensors. I noticed a buildup of pink crust, indicating coolant leaking and traced the source to this vent.

My question is, how much venting from this port is normal. I observed a single drip below the hole when I got back from my drive but I could tell that at one time it must have squirted some out about an inch or two based on the staining patterns. It doesn't look like a serious problem right now but I want to know if this is a sign of problems to come.

Thanks,
baetke

Z07

Water pump weep holes are there to keep the pump's bearings from washing out and failing catastrophically once the seal starts to leak. There are only two kinds of automotive water pumps, those that have failed and those that will.

Your water pump is talking to you. It is saying "soon soon soon soon and when you are least able to deal with it."

BTW is your RX over 100K miles? If so, was the timing belt replaced? And was the water pump replaced at the same time?

FWIW my local dealer wants $1,500 USD for a timing belt and pump repair. YMMV

Baetke

I am at 155,000 miles and the timing belt was last done at 92,000 miles. No water pump done at that time so it is the original. I was planning on doing the belt/idler/pump at 180,000 miles. Do you think I will make it or should I start looking for a shop to do the work now?

One more piece of data: I did a cooling system pressure test and it does not hold pressure very well. Leaks down about 1 psi every 5 seconds. Could this be caused by the leaking bearing?

Z07

Understand that the pressure in the system is what keeps the water from boiling. For example a 15Lbs radiator cap will keep water from boiling until about 255F.

So the leak is letting air in and coolant out and lowering the boiling point to something just above the normal 212F.

My risk tolerance and yours are likely different. Were it my car I would probably carry pre-mix coolant, top off the system at each stop I make, and order the parts online for low price now and figure on doing it myself in two weeks or less.

If it were my wife's car I would put her in our third car and get it fixed now or pay local prices for the parts and do it next weekend.

Stay safe!

Baetke

Thanks Z07,

I'll be checking in with my mechanic real soon to see about getting this done. I assume I should just go ahead and put a timing belt kit in as long as he's in there.

Z07

I would change the belt while in there just to reset the 90-100K clock on this chore. The parts are a tiny portion of the repair cost.

I am no fan of miracle cures in bottles. I consider most of them snake oil and the venders prey on people in distress.

With that said, I want you to consider a specific bottle/tablet called "Bars Leak". I know for a fact that this is part of the factory fill for several high end cars. I use it whenever I flush and fill. It is not a miracle cure. It won't stop all leaks. It won't magically repair worn water pump bearings or failed heater hoses.

It will stop small leaks. It will help prevent future leaks. It cannot harm anything.

But I encourage you to do your own research.

Baetke

I'm familiar with the Bars stop leak products and have used them on my 69 corvette and my 86 MR2. In both cases they caused more problems than they solved and I wound up doing the proper repairs soon after anyway. They may be ok in an emergency to get you to a mechanic but I have found that they plug up the radiator, heater core and head gaskets just as effectively as any small coolant leaks. With modern radiator designs that have the super small coolant passages I'd be scared to death to try any stop leak product in the cooling system for fear of ruining a perfectly good radiator.

Z07

It is funny you should mention a Corvette as Gordon Killebrew is the one who turned me onto Bars Leak. In addition to writing it in the FSM for our Corvettes, GK is the one who told me it was factory fill for Caddy and Corvettes for years. My wife's is for sale being replaced by the RX. My Z07 is being converted from track car back to street and I'm debating keeping it or getting something else.