'98 Volvo S70 Coolant Flush issue

dcmatos · Post by **dcmatos** » 06 Sep 2017, 19:48

First gentleman, I should say that I do not know what brand the previous owner purchased for the replacement of the original radiator.

It's been about 3 years since I originally bought my Volvo, so I figured it was time for a coolant flush. I bought coolant and the necessary tools, since it's pretty simple. I get under my car to unscrew the petcock, and it is not there!

All I see is this tab where the petcock should be. I have attempted to unscrew it, however I cannot turn it more than 90 degrees. Is there a another way I can flush the radiator? If not, is there another way to drain the coolant and replace it? My coolant is pretty degraded and my Volvo is beginning to run hotter than usual.

Post by **theWIFES_S70** » 06 Sep 2017, 20:15

Be happy your petcock isn't weeping! I don't think i will open up my petcock ever again. It broke once and just don't feel it's worth it.

Just crack open the lower radiator hose clamp and pull it off. It'll be a little messier, but it should be quicker.

Post by **erikv11** » 06 Sep 2017, 20:22

What Marco said - unscrew the clamp on the lower rad hose, get a bucket under there, dislodge the hose, and the coolant will all come pouring out.

Post by **wizechatmgr** » 06 Sep 2017, 20:33

Looks like the radiator that was in my Dodge Caliber, you rotate the petcock 90 degrees and then pull on it.

That said, just in case that isn't it, I'd recommend the lower radiator hose...

Post by **abscate** » 06 Sep 2017, 23:56

That's the new Nissens radiator type like mine. It's a 90 degree CCw rotation and pull over the oring resistance. Reverse to reinstall. It probably is one of the few improvements over OEM

Interesting. I searched the forum on topic ' Nissens radiator petcock' and found some folks got the 1/2 turn style back in 2011. In 2013, I got a conventional screwed in petcock which I snapped off , of course.

It looks like I either got old inventory or there was a mix.

I replaced it again in 2017 and it has the 1/2 turn style

Post by **sleddriver** » 07 Sep 2017, 13:07

+1 on removing the lower radiator hose.

Also consider a citric acid cooling system flush before adding new coolant.