Mystery coolant leak on V70 T5, 1997

whoa · Post by **whoa** » 29 Jan 2013, 13:02

Yeah, I agree with you there.

I have had a leak from a small crack in the bottom of the reservoir (like T5erry describes above), which sprayed coolant onto the timing belt cover.

I replaced the turbo coolant inlet hose today (and also the little turbo outlet hose at the top-back of the engine, which I had been meaning to replace whenever I next drained the coolant. I sure hope that was my issue...

V70T51997 · Post by **V70T51997** » 30 Jan 2013, 07:00

I've checked the reservoir and although it has a tiny crack, I don't think that it is the reason (the crack is on the upper hose nipple). There has been coolant on both sides of the timing belt cover. The outer side splashes could be explained by the spinning drive shaft but the inner... Don't know for sure.

I'm going to jack the car up, remove left tire and the timing belt cover to check it through there, hopefully there are no leaks now... There shouldn't be as I've not driven the car in 2 days now...

Please reply as soon as you have had enough testing with your car, whoa. Maybe I can get some advice out of your experience! Sooo frustrating...

whoa · Post by **whoa** » 31 Jan 2013, 21:27

Looks like that was the leak in my case. I haven't done a huge amount of testing because I've been called out of town, but a couple of 60-mile drives yielded no leaking. I'm worried about the heater hoses, which are now the only coolant hoses I haven't replaced. They seem kind of spongy. I like the idea of replacing them with continuous 5/8" heater hose run straight through the firewall.

Post by **pkc303** » 04 Feb 2013, 00:08

My leak on the V70 turned out to be the rubber hose on top of the overflow container. It would drip ever so little after driving, when the pressure built up. It dripped behind a part of the engine that was not normally visible, and land on the block, where it would boil off during the next drive cycle. I think it was just behind the power steering pump. I replaced the hose, and my leak was fixed.

V70T51997 · Post by **V70T51997** » 05 Feb 2013, 10:20

Thanks for the tips! I haven't done anything for the car for 2 days again, I've test driven it on the weekend and although I doubled the mileage (70 km) the coolant level still dropped. And I haven't had any motivation towards the car for a few days now... It's getting colder outside too so that's one part and the other is that I'm starting to feel quite bankrupt.

But life goes on. Hopefully I'll find out the leak and hopefully it won't be the head gasket.

V70T51997 · Post by **V70T51997** » 06 Feb 2013, 06:58

Last night I used a hot iron weld to melt the upper cracks on the thermostat-to-reservoir -nipple, and took some extra material from the reservoir tank and made it quite nice (not perfect though). Results were the same; only now the upper nipple is sealed nicely. I tightened the clamps nice and tight. Then I filled the reservoir to max level and took a 20 km ride. The coolant level drains still (no excess pressure on the reservoir, but enough pressure somehow, that the coolant level will drop down to a point in which the coolant level sensor is telling me that the coolant level is too low). Then I pulled aside, opened the gap a bit (too fast again) and some coolant came out the reservoir. The coolant level then rises up to almost the upper level, and after the gap is closed, the level drops as soon as there's enough pressure to "push it down". The level won't rise or go down if the gap is off and I rev the engine a bit.

Is there any other possibility than the head gasket?

V70T51997 · Post by **V70T51997** » 14 Mar 2013, 16:18

Yeah it was the head gasket, leftmost rear head bolt was really loose and it had therefore leaked coolant out of the engine. Plus there was a 15 x 5 mm hole on the head gasket too, which then lead the coolant on to the first three cylinders. Only that little so you couldn't see the coolant looking through the spark plug holes. I replaced the gasket and everything is now under control. Thanks for the tips though.

Post by **cn90** » 10 Apr 2014, 18:23

I have come to accept that it is "normal" to lose a cup of coolant every 10K miles or so.
I top up the reservoir with a cup of coolant every 10K.
My theory is a tiny amount of coolant escapes from the cap as vapor when the engine is hot, so over time it adds up.

- Engine is fine, no issues so far.
- Heater Core: no leak.
- Both turbo coolant hoses are new
- Radiator: new
- Reservoir: new
- Water Pump: new

No external coolant loss.

This leads to a question: what is you guys' "normal" rate of coolant loss?

Post by **rmmagow** » 11 Apr 2014, 13:40

Bought my car w/155K on it, I now have 214K and have added about 1.5 cups of plain water to it once, that's about it. No flush or new hoes installed yet, maybe this summer but also maybe, leave well enough alone and just change tranny fluid a bit more. Previous history unknown.

Post by **j-dawg** » 11 Apr 2014, 15:02

i'd change that coolant if i were you. every 30k is i think the spec. neither a hard nor expensive job.

Mystery coolant leak on V70 T5, 1997

Re: Mystery coolant leak on V70 T5, 1997