Can't find the leak

I have a '98 Volvo V70 that has a slow leak in the cooling system. I have brought it to my indie Volvo mechanic several times and they keep trying new things - they’ve replaced the thermostat, all the hoses, overflow tank, and this last time used Stop Leak in case I have a bad head gasket. I’m 4 visits and $1600 into this repair, and it’s still leaking. Now they’re saying it must be the head gasket and it will be $3000 to fix. What do I do??? How do I know it will fix the car and when do I ask for my money back? When do guarantees come into play? Is the car worth it? It’s worth nothing with a leak, so I’m stuck in this corner. Anyone have any advice?

Clearly, they are guessing. $3000 is an expensive guess. I’d go elsewhere.

You don’t mention how you know there is a leak, and apparently it’s not visible because of the different parts that have been replaced.

Evidently you must be seeing the coolant level dropping in the reservoir without any external evidence of leaking, e.g. coolant dripping out somewhere. Is that correct?

If that’s the case, it’s very unfortunate that you spent $1600 throwing new parts at it. In a case of disappearing coolant with no external evidence of a leak, the culprit is almost always a bad head gasket, and the coolant is being sucked into the engine and burned. (I assume your mechanic has checked the condition of the engine oil and verified that coolant is not getting into the oil).

It seems you’re left with what should have been your mechanic’s first hypothesis: a bad head gasket.

The first thing I’d do is find a new mechanic. $1600 for new hoses, thermostat and overflow tank? All of which were obviously not leaking? Ouch.

Use the Mechanics Files to find a recommended Volvo mechanic near you:

Thanks for the advice… Yes, I can see the level dropping in the reservoir and the warning light comes on whenever it gets too low, but haven’t seen any coolant actually leak from the car. There seems to be a huge amount of pressure in the system and I do see some coolant around the cap on the reservoir. Wondering why the system has so much pressure and wondering if the coolant is all coming out the top and burning off.
These guys have been great in the past and I’m upset that I can’t trust them anymore.

A head gasket leak can add lots of air pressure to the cooling system. Any reasonable mechanic should be equipped to test for the presence of exhaust gases in the cooling system. That’s why I don’t understand them guessing at it. Test and be sure.

Some shops specialize in the HVAC aspect of cars. Some would still be called “radiator” shops. Perhaps its time to check out the yellow pages for a local shop that specializes in cooling systems.

I had the same story. Then I started having transmission problems. I took the car in to have the transmission fluid drained and refilled. The mechanic called and said he found the source of the mysterious leak. The coolant had been leaking into the transmission fluid. Please check that before you ruin your transmission!!

Sounds like a classic head gasket issue. HOw much coolant are we talking about here…and how fast? One way to see if shes burning coolant is to look at your exhaust pipe. Do you see puffy white clouds of “smoke” out of the tailpipe? You should when shes warming up on a cool morning but after its HOT…you should NEVER see puffy white smoke from the tailpipe…the “smoke” is actually steam and sort of Oil fog…Ethylene Glycol has an oily consistency and smokes like hell when burned…You can also smell it from the tailpipe.

Also the other clue is the overpressure of your coolant resevoir…it gets pressurized from leaking piston compression past the head gasket and into the coolant system…

As for quick fixes? BLUE DEVIL…Works like a charm. Even on seriously cracked heads it works. I should get paid for how many times I recommend the stuff, but when I find a product that works as good as Blue Devil…I surely dont forget it. SOme of my friends are approaching 80K miles on a Blue Devil repaired head gasket…No S&^% ! I havent seen any other product work like this stuff…its AMAZING and is probably your cheapest solution, bec its permanent and if it doesnt work your money back…YOu MUST install it correctly however… You could most likely save that 3000 just by buying a 60 bottle of BLUE DEVIL… I am not affiliated with Blue Devil at all…just a very happy consumer…and I have leagues of friends that have used it…only once…thats all it takes.

Even though I have used it…its only temporary for me…being a mechanic…I will use the Devil and then save up for the parts to tear down my engine, cut my cylinder head and do the job correctly…but I dont have to pay myself 3000 to do this so… for the average person this product WILL save your ass… I promise.