Have an opportunity to pick up a S70... But...

Post by **theWIFES_S70** » 08 Jun 2017, 15:26

It's been sitting for a few months. The owner had a leaky radiator for a long time. (I offered to fix it for him but he never took me up on the offer.) Now says he thinks the car needs a new head gasket... I don't know if he really understands these cars too well. I certainly think the car could've have severely overheated, and thus necessitating a head gasket job.

But my question is this:

What do I need to diagnose this car? I can pretty much pick up the car if I want it so it might not be a bad car to practice on.

I'm thinking a compression tester and a coolant gas tester, right? Any other tips?

Post by **bmdubya1198** » 08 Jun 2017, 16:50

You can get something to test for oil in the coolant, and a compression tester wouldn't be a bad idea. Otherwise, everything can be checked visually, like the oil.
Just make sure to check out all the basics for these cars...

Post by **FLXC90** » 08 Jun 2017, 18:39

Yes coolant/exhaust gas tester, because these cars will breach the cooling system and not lose compression, it is necessary. The compression tester can tell you ring status, and if you have/can borrow a leakdown tester that will give you more.

Bang for the buck, start with the gas tester. (then you can get it for 2 or 3 hundred bucks if it's worth saving. POS70 has served me well for almost four years now, was $300 and I think I'm up to about 11 hundred. Daily driver. Still a beater.

Post by **theWIFES_S70** » 08 Jun 2017, 19:33

Thanks for the replies, guys. How reliable are those coolant/exhaust gas testers on our whiteblocks? I read somewhere that those things work better when you can directly connect it to the radiator. I can pick one up at AutoZone, right?

One other thing, if there's a small head gasket leak, I wouldn't see any "cream" in the oil, right?

Post by **erikv11** » 08 Jun 2017, 20:41

Head gasket separates 3 compartments: coolant, oil, combustion. A leaky head gasket can involve any two of them or all three of them, and the leak can be in one direction or both ways. So yep, there are plenty of leak possibilities where there wouldn't be any cream in the oil.

The exhaust gas testers are not exquisitely sensitive. If you get a positive result, there is no doubt the gasket is breached. But a negative result you can't be totally sure. Autozone should have it but I've never actually looked for it there. NAPA stores usually have them, if that helps.

I agree with FLXC90. Do the combustion gas test, see what you see. Get the car warm first, drive it if you can? Definitely eyeball the oil for cream on the dipstick, simply eyeball the coolant reservoir for oil residue (or boiling coolant gases!), oil in there is usually very easy to spot.