Volvo Aqad40a Losing Water

[capelsound]

Hi, My volvo is running well, but it is losing water. If I take it for an hour run it drops about 2 inches in the tank. The engine does not run hot ( about 65-70c). It blows a little black smoke when you increase speed, but only for a second or so. Any suggestions?

Thanks
jim

 

[Don S]

Re: Volvo Aqad40a Losing Water

Did you look the engine over for signs of a leak? The head gasket on the starboard side of the engine, and the gasket between the turbo and the exhaust manifold are a couple of places prone to external leaks. Of course the circ pumps also can leak, and there are all those seal rings on the copper tubes.
The burst of black smoke on acceleration is normal.

 

[flabum]

Re: Volvo Aqad40a Losing Water

If it's not showing up in the bilge, it may have a heat exchanger leaking.


How does the oil look? any signs of water in the oil?

 

[capelsound]

Re: Volvo Aqad40a Losing Water

Thanks, The bilge has coolant in it and the oil is black. Cant find a leak anywhere...

 

[Don S]

Re: Volvo Aqad40a Losing Water

If the coolant is in the bilge, then you have a leak. Drain the coolant out of the engine, manifold, and heat exchanger. Then pressurize the system with air to about 12 or 15 psi.
Then spray EVERYTHING with a soapy water solution. It will bubble where the leak is.

 

[capelsound]

Re: Volvo Aqad40a Losing Water

Thanks Don, Exscuse my very poor mechnical knowledge but what is the best way to pump the air in? jim

 

[Don S]

Re: Volvo Aqad40a Losing Water

Personally, I have a pressure regulator and a gauge with a hose and fitting that I screw into the block drain. Then I pressureize it to about 15 psi and spray the soapy water on it.
You can also get a radiator tester that just twists onto the heat exchanger fitting where the cap is. And just pump it up. It will take a lot of pumping, but will work. You can probably rent a tester at an auto parts store.