Would it be possible to clear out a gummed up PCV instead of replacement?

AylmerQc · Post by **AylmerQc** » 30 Jun 2024, 19:33

2007 XC70 Cross Country...
Three different inspections from different garages have diagnosed a need to replace the pcv on my Volvo. (The one garage didn't come across as very reliable or honest, the second just gave it a quick cursory inspection and the 3rd garage was more thorough and came highly recommended from an another Volvo owner).
I was mentioning this and the work and parts involved to my older brother, a non-Volvo owner but quite a hands-on fellow who wondered if there was a possibility of blowing compressed air up or down a passage way to the pcv to unclog it instead of removing the intake manifold and all the other work involved.
I'm guessing if there was such a way someone here would have tried it or mentioned it but all I've read is the 3-4 hour method with the
complete pcv kit.
Is it possible?

Post by **Krons** » 30 Jun 2024, 19:41

Possible, yes, worth it in my opinion, not a chance. Way too much labor if you have to redo it. It’s a $57 part. More you’ll need to do the job right.

Post by **scot850** » 30 Jun 2024, 19:45

The catch tank may be $57, but the pipes are wicked expensive. I have never seen a badly clogged oil separator tank. The bottom outlet and pipe into the drain to the block can be an issue, and the mid pipe into the block also. The rubber pipework is the bigger issue. Look for cracks in the pipes, in particular where it connects to the block on the RHS.

Neil.

Post by **Krons** » 30 Jun 2024, 19:50

scot850 wrote: ↑30 Jun 2024, 19:45 The catch tank may be $57, but the pipes are wicked expensive.
Neil.

Yea the full kit on FCP is $475. IMO for any car you plan to keep it’s worth it to not not have to redo the 8+ hour job.

Post by **Blacklab467** » 30 Jun 2024, 21:33

Short answer is no, the labor required would be the same as replacing all of it anyway. I kept all my old stuff for months after replacing the PCV and associated plumbing thinking I would take a stab at cleaning it and decided that it was in no way feasible.

Post by **Twarr12000** » 30 Jun 2024, 23:23

OP is talking about blowing out the PCV without taking everything apart

OP - It’s really not feasible. The hoses need to be replaced. It’s not just a matter of plugging but the hoses harden and crack. And the crud that blocks the passages is very hard. Especially at the connection on the bottom of the trap that returns the condensed oil back to the block.