1997 850 wagon disappearing coolant

Tobers · Post by **Tobers** » 17 May 2015, 14:22

My daughter's 850 loses about a reservoir of coolant every couple of weeks. I've looked everywhere; no trace. So today I let it run for 30 minutes in my driveway. The fan was running. It was at full operating temperature. No sign of coolant anywhere. So I drove it a few miles, and watched it some more. Not once could I find a drop. I changed the water pump less than 5k ago, so I doubt that's it, and I'm guessing if it leaked there it would drip out the bottom somewhere anyway. It runs great. I tried to get a coolant system pressure set up from OReilly's, but it didn't fit the Volvo. Next steps? Thanks. Rick

Post by **j-dawg** » 17 May 2015, 14:53

Any white smoke in the exhaust? Have you checked compression? Abnormalities in these might suggest you're burning coolant and sending it out the tailpipe, hence why you wouldn't see it dripping.

Tobers · Post by **Tobers** » 17 May 2015, 14:55

by "compression" do you mean testing each cylinder for compression? I'm sorry if this is a dumb question. thanks. Rick

Post by **FLXC90** » 17 May 2015, 15:07

A compression check may or may not tell you anything. The Volvo "White block" design is known to pressurize the cooling system if there are small breaches in the head gasket. Search this forum and you will find references to small amounts of coolant being "used". The sneaky part is, that it won't show much on a compression test. A block test kit may reveal exhaust gas entering the coolant system: it uses a reactive liquid, and a gas-permeable barrier in a beaker you place on your coolant reservoir. Some owner's have driven their cars for a year, minding their coolant level, before having to perform repairs. Also, have you checked for leakage in the heater plumbing? it could be inside your car, and not dripping outside.

Anybody else know where other "sneaky leaks" might be?

Tobers · Post by **Tobers** » 17 May 2015, 15:34

I replaced my heater core 12 months ago. I doubt that's it. No white smoke out of exhaust that I'm aware of. But I am throwing a p0303 code. I changed my distributor cap and rotor (they were bad), but I'm stilling throwing it. Also, occasionally at cold start it shutters (I know my SAS/airpump aren't working right, if that matters). I think those can be related to a head gasket failure. Obviously I'm hoping for the best, and looking for the best way to determine what's going on. thanks! Rick

Post by **abscate** » 17 May 2015, 19:32

Take a good look at those plugs when you pull them. If they all look normal don't sweat the coolant use

Post by **erikv11** » 18 May 2015, 07:51

A reservoir of coolant every few weeks is a lot, I would not ignore it, no matter what the plugs look like I would get to the bottom of it. Smell the exhaust, is it sweet? Are the carpets dry in front (even though you recently changed the core)?

Post by **850 LPT** » 18 May 2015, 08:04

I had the same problem and was loosing coolant at about the same rate as you. I took me a while to find, but it ended up being the small hose that dumps coolant into the reservoir. The leak was small enough that no drops ever hit the ground.
That hose connection at the reservoir seems to be troublesome. When I got my 850 a few weeks ago, it leaked at the same spot.

Post by **MrAl** » 18 May 2015, 09:19

Hi,

Yeah i was going to say that if the leak was small the water could evaporate when it hits the engine block so you'd never see it. Depends on how bad the leak is though.

obayha · Post by **obayha** » 18 May 2015, 09:28

I have the coolant system pressure cap needed for testing the system if you live anywhere near Salisbury, N.C., as I see you are in NC.
Shane