I've been trying to track down this slow coolant leak for a while. He recently replaced the radiator, and I've had it in the shop two times since to track down the leak. On Friday, after failing to find any "external leaks" my mechanic finally said that it must be a head gasket leak, and to live with the slow leak.

Today, after the car had been sitting since Sunday evening, I noticed a small puddle under the car. On the passenger's side, following a drip of coolant up from the front cross member just behind the Evaporative canister, I come to a cylindrical horizontal object that the accessory drive belts run around. It is at the front of the engine (obviously) This cylindrical part is machined in two pieces and joined together. There is green coolant leaking from where the two parts join together.

In the Haynes Manual, on page 1-21, drawing 30.9 shows the Auxiliary Drivebelt Arrangement and it is on the lower right, as it would be if you faced the engine from the passengers front fender looking across the car.

What is this part? Is it reasonable that coolant would be leaking from this part?

Seems unlikely to be the water pump as that is at the "rear" of the engine, meaning toward the firewall, not toward the radiator side (though it and timing belt are technically at the front of the engine). The water pump is indeed driven by the timing belt. You can't see the water pump unless you remove the timing belt cover. The upper cover comes off with 1 bolt and if you remove that you might be able to see enough of the water pump to see if it is leaking.

Could you maybe provide a photo or a more detailed description of where the leak is from?

Water pump.

...Lee

As I suggested to my mechanic originally. :-)

When I asked him whether he had changed the water pump when he had done the timing belt two years ago, he said you only change the water pump on the second timing belt. I'm surprised the water pump is external - do you have to remove the timing belt to do this water pump, like my Miata? What's the going rate for a water pump?

Thanks!!

The water pump is driven by the timing belt but the leak will show up at the bottom of the cover.

Standard procedure is to change the water pump the pulleys and the tensioner on every other timing belt change but standard procedure goes out the window when a coolant leak appears at the bottom of the timing belt cover.

Don't mess with it since it could seize up and take the timing belt with it. Bent valves and much grief follows that episode.

...Lee

Yes- It's the water pump. You confirm that replacing the water pump is every other Timing belt, as my Mechanic said. I would replace the water pump every time you're in there (and save $1000). The mechanic wants $1060 to do it, but another place I go to wants $700. The mechanic says I don't need to do this immediately, so I'm think of waiting a couple of weeks, until after my vacation next week (not driving the Volvo). You think that's dangerous to put a couple of hundred miles on it before I have it changed?

Hi Larry,
Do you like playing the lottery? Driving with a waterpump like that is much the same.
I have exactly the same problem with my 1994 850T at the moment and am waiting for the parts to arrive from the US as they are cheaper to get over there than in Australia.
I will reluctantly drive even 10km in the car as the cost of a broken timing belt is horrendous especially in Australia.
I would hate to think how much a shop would charge me to do the job so will be doing it myself as I have the tools and knowhow.
All the best.