Oil Leak at Oil Pressure Switch (04 XC70)

[BlackBart]

When I was under the car this weekend I discovered an oil leak that appears to be coming down the block on the radiator / left side of the block (forward). A lot of plumbing and hard to see in there, but I think it's this pressure switch low on the block.

https://www.volvopartswebstore.com/prod ... 45696.html

Anyone had trouble with this?

It's either-
It's backed out with vibration.
Someone forgot to put the crush washer in.
The housing cracked.

I'll see if I can get a hand up in there to check.

[wahiddd]

Your guess is on the right track and assumptions are also true.
I would try cleaning the dirty area with some cleaner to be able to localize the leak, maybe upload a photo of the area, which could help us locate it easier

[jonesg]

in the same vicinity it could be the dipstick O ring.

[BlackBart]

OK, thanks, I'll check those.

[BlackBart]

While I was replacing the o-ring on the filter cartridge I wiped everything off and reached up from below. Just enough room for your arm between the subframe and the pan flange. You can reach it with a long open end - I went through 17, 19, 21...nope! That's the biggest open end I have.

So I got this bad boy antique in my drawer out and somehow it fit. Snugged it up, I'll watch it for leaks.

15/16 and 1 1/16, curious what it was for - an old machine shop? By my calc 15/16 is 23.81mm, so do you suppose that's a 24 mm hex on the sender? It worked!

[scot850]

That is funny, I have found that a 15/16" wrench has come in useful over the years on various Volvos. Most of my tools were bought metric, but I have a fair number of imperial dimension tools also. One of which is a combo 15/16" with open end and ring end on the other end.

Neil.

[BlackBart]

I think this came from my old neighbor, who was 96 when he died. He would come over when I was tinkering and give me some old tools.

I have a friend who bought a set of Whitworth's for an ancient MG. Useless after the car was gone.