New water pump leaking. Duff o-ring?

[hill8570]

Finally bit the bullet over Memorial Day weekend and tore down Little Green ('95 Camry 2.2L) to change out the passenger side oil seals. Since I was in there, figured I'd replace the timing belt, water pump, and idlers even tho the water pump and timing belt only had about 50K miles on them (not sure about the idlers). All in all, went pretty well, just the usual crap that goes wrong on a big job.

Problem is, I'm losing coolant (and I can see water drips at the bottom of the timing cover...do the math). When I was installing the water pump, I thought the o-ring that goes between the WP housing and the head (or block? wasn't paying attention) seemed a mite small, so that's my first suspect. Second possibility is that I screwed up cleaning the old gasket off the WP housing, but I'm generally pretty anal about that. Didn't use any RTV, just hit the paper gaskets with Copper Coat before installing.

Anywho, has anyone else run into a case where the o-rings with the replacement water pump (this was a GMB pump, not Toyota, but GMB is generally decent quality) weren't quite right?

On the bright side, I've yet to see any oil drips, so at least I fixed what I went in to fix. I think. Maybe. Shit...I'm so jinxed now....

[Chris Crash]

Personally never had this problem. But it sounds like you're right about the o-ring being incorrect. I suppose either way you gotta pull the water pump off again anyway...unless you don't mind losing some coolant and topping off every now and again.

[mail2_jb]

I used an ebay kit and (with new aisin water pump) and the gaskets/o-rings are perfect. No leaks. I didn't use copper coat, the gasket was not paper. It is kind of metal. I just bubbed off the old gasket/o-ring area and put the new water pump.

[carsrus]

First check the two pipes that go under the exhaust manifold. Maybe you'll get lucky and its coming from there.

[hill8570]

Originally Posted by carsrus

First check the two pipes that go under the exhaust manifold. Maybe you'll get lucky and its coming from there.

I wish. Both bypass pipes connections and the WP outlet connection are all dry as a bone. As is the part of the WP gasket that I can see without pulling off the upper timing cover.

I ordered a new WP gasket and o-ring from the stealership this morning...should be able to get in there this weekend.

[hill8570]

Originally Posted by carsrus

First check the two pipes that go under the exhaust manifold. Maybe you'll get lucky and its coming from there.

Well, you were almost right, and I'm really pissed off at my lousy diag skills on this one.

I went back in as far as getting both the timing covers off, and, lo and behold there wasn't a trace of water leakage anywhere behind the covers (no oil leakage either, so that makes me real happy). So, I started hunting around so more, and found a little pink trail (whatever else you can say about Toyota Red, it definitely leaves a trail) coming down the front of the A/C compressor and thence to the bottom of the timing cover. Tracing it the rest of the way back, it turns out there was a tiny leak from the thermostat gasket. Just my luck it all went forward instead of puddling against the engine like it usually does on a t-stat or bypass pipe leak. Since I'd just replaced the thermostat 3 years back, I hadn't even messed with the t-stat, but I guess while I was dinking around with the rest of the water pump, I managed to piss off the t-stat gasket. Weird.

After replacing the gasket, things are looking a lot better. Since my system is still in the "get rid of the last few air bubbles" stage, I'm not 100% certain there isn't a tiny leak still lurking, but I think this got it.

Thanks for all the suggestions, and I hope this tale of stupidity helps someone else along the way.