PCV time means question time! Topic is solved

[TisMe]

Hey folks, it's looking like it's time for me to do a PCV overhaul on my '01 XC70.

I've had a small-ish oil leak for a good while now, and I always assumed it meant I needed to replace an engine seal or two. My turbo has always performed like a champ, so I assumed the previous owner overhauled it fairly recently. However within the past month, the leak has worsened in the form of consistent white smoke coming from the rear of my engine block. I'm starting to think I'm getting a fair amount of blowback from that traditional sludge buildup. If I'm lucky, the PCV has been the culprit all along and the seals are intact.

I've watched several videos and noticed that a lot of people only replace their oil trap. I thought this was odd considering the kits out there always include the hose assembly that goes horizontally across the engine bay. Is this the result of people trying to save money, or is it typical to only need to swap the oil trap?

Speaking of saving money, I noticed that IPD has this kit that they say is as good as, if not better, than the OEM kit. Does anyone have any thoughts or experience with the quality of this kit? Figured it's worth asking, considering it's nearly 50% off the price of OEM from FCP.

I've also noticed that if you buy just the oil trap, that's a cool $50 for an OEM replacement. I can see why a good number of people have replaced just that one part, but if I'd likely need to go back in again sooner than later to replace the hose(s), I can't imagine those savings being worth it.

Any input will be much appreciated, thanks!

[leapdragon]

FWIW anecdotally, I've done this three times now on three separate V70/XC70 cars, each time with the $150ish FCP Euro kit (includes the rubber hose going into the top of the head, but not the larger hose assembly that apparently boosts the kit up over $400).

I have never needed the larger, more complex hose, as it and the PCV nipple going into the plastic turbo pipe near the turbo have always been entirely clear when I checked them.

However, each time the metal elbow to the banjo bolt and the rigid center tube coming off of that elbow have been clogged solid.

First two cars, I cleaned out the metal elbow and actually just replaced the rigid hose with silicone tubing with no apparent ill effects over a combined 100k miles or so, but this last time I actually ordered the "right" part (metal elbow and rigid hose only), which isn't officially sold for V70/XC70 but there is a part number for one of the other models that will fit perfectly (thanks to the FCP Euro video on PCV service for revealing that) it's here: https://www.fcpeuro.com/products/volvo- ... t-30731007

The main clogs in all three cases were on the lower port on the engine block. In two of the three, it was 100% blocked, in the other case about 95% blocked. I used picks and a shop vac to break up the debris and get it out in each case. Then I used a length of rubber hose to blow into that port just with my own breath to make sure I could hear oil bubbling on the other side (i.e. not blocked all the way into the pan).

After finishing the PCV in each case, I've run full synthetic thereafter (Pennzoil Ultra Platinum) to try to ensure that as I continue to drive I'm breaking down any remaining sludge rather than building it back up.

I doubt the box itself matters all that much. When I've done these at least, it's always basically empty and 100% intact. It's the port going into the engine block that's the real problem, that and the metal elbow/nipple+short center hose coming off of it. It's more of a "might as well replace it while I'm in there" sort of a thing, but I imagine aftermarket would be fine. Be sure to get all the accompanying little parts though... The two bits of very short hose/tubing to get the box mounted to the block, the hose that goes from the top of the box to the top of the head/valve cover, the intake gasket, and preferably also the throttle body gasket since with the manifold off you're going to want to take the opportunity to clean out your throttle body with some throttle body cleaner (always lots of varnish and gunk). Oh, and all the clamps. Those are pretty important, too.

The first two times I did it I just shoved the fuel rail back into the manifold when reassembling, but this last time I figured I was tempting fate and I replaced all the o-rings on my injectors as well before reinserting.

Three notes:

1) Be careful if you suspect you have a PCV problem and don't drive much. The first one of these I did was out of necessity. As I was pulling into the driveway (luckily) all of a sudden oil was pouring out of the bottom of the car like a waterfall. Turns out the pressure had blasted a cam seal right off of the cam as I pulled up. If I'd been driving down the highwayI could well have locked up the engine due to no oil left in the crankcase.

2) The biggest frustration points doing the PCV are the stupid bolt at the lower left of the intake manifold (get a small 1/4" ratchet and a bunch of variable length extensions and wobbles or you will be swearing for hours) and the banjo bolt on/off (just get an old fashioned, thin steel open-end wrench and be patient, and careful not to drop the bolt or the washers as you fight it).

3) The only real "oh crap" I've had doing them was the first time. Be careful putting on the short rubber elbow that goes between the breather box and the engine block. It's relatively thin and easy to get the edge that you can't see folded over rather than seated properly under the clamp. First time I did it, I wasn't careful enough and ended up with a fairly significant oil leak after I'd put it all back together. I then had to take it all back apart, track down the problem, and then visit my local Volvo dealer for that piece of rubber because the first one had been damaged when folded over and then clamped down that way.

Good luck! Plan to spend a full afternoon (say, noon to evening) if it's your first time doing it, it's a fiddly PITA job.

[TisMe]

Nice Leapdragon, thanks for all the personal insight!

Sounds like I'll take the time to source all the individual parts from FCP or IPD, and skip the long hose assembly (as long as it's not brittle upon next inspection). You answered one of my questions I'd already been wondering, which is whether that long hose tends to get clogged. Sounds like it's typically just the metal elbow, which explains why so many guides and videos never even showed the long hose.

I'll probably get a new oil trap just in case, although as you mention, it's just a plastic box so I could probably just clean it out. Hmm...

I actually cleaned my throttle body last month while trying to diagnose my cylinder 3 misfire, so that has a fresh gasket on it already. That service improved my hunting idle during cruising conditions. That's probably a story for another thread, but I will say that I replaced a lot within my spark system which gradually improved my crank, idle, and cruising stability.

Several people have seemed to cure their misfires after rebuilding the PCV system, which is part of why I'm moving in this direction. And even if it doesn't, preventative maintenance in this realm could surely save my engine seals down the literal road.

I put 30K on this beast my first year of owning it, so suffice to say it doesn't sit around too much. Mostly highway miles, so the system never really struggles for some good air. However the consistent smell of burning oil and increased vapors from under the idling hood is finally getting me to take action, and to take the last step, to see whether a seal or two really is getting blown out. I'm thinking an unserviced PCV is finally rearing its mane, and potentially giving false-positives in other directions.

If this cures my P0303 that'll be icing on the cake. We'll save the discussion of potentially burnt valves for another time.

[TisMe]

So now that I know exactly what this hose does, I've realized that I should in fact order the entire PCV kit. I'd already been eyeballing it wondering when I would get around to it, but now I know the answer. Check it out:







Apparently some heat transfer between the hosing and this poorly reconfigured wiring from the previous owner/mechanic resulted in the wiring melting down the hosing. You can also see in the last photo between the manifold where the rubber has been melted away, and leaves a window into the metal tubing.

I'd say it's time for a full swap.

[Georgeandkira]

I have one. My earlier V70s had a fuel line which needed disconnection. A connection was snaked through the intake runners.
I remember reading that the newer of these fuel line couplers could be pivoted in place.

All of that seems to have gone away as there is no connection visible at all in my 2007.

My question is: Where is the break in my fuel line? I'm due for PCV replacement too. TIA

[leapdragon]

So I can't remember the exact details, BUT on my '07 XC70 basically the fuel line is underneath the rail and is hard.

If you take off the plastic rail cover (two T30s, I think?), on the back of the rail (note position of intake pipes in the photo below vs. fuel line, in red square) there is a latch of some kind. You undo the latch and then when you unbolt the fuel rail and pull it, it pulls out both the injectors and the hard fuel line at the same time. I think the latch may have a tiny Torx head screw holding it closed or in place (T10 maybe? Not sure, going by memory here.)

When you put the rail back on, you just shove it carefully back into place. Injectors go into holes and the fuel line is inserted in the same motion back into the back of the rail. Then, you close the line latch on the back of the rail and re-insert the small Torx screw to solidify the connection. Wish I could remember what it looks like, but I do remember it wasn't hard to figure out and doesn't feel sketchy or anything.

[TisMe]

So the stars have aligned, and the parts gods have delivered, and it is now time for me to rebuild my car's lungs. However, I cannot seem to find any information on removing the long horizontal hose that goes from passenger to driverside. All the information I can find, which is a lot of guides and different videos, seem to not bother removing the long hose, and instead simply replaces thePVC pipe.

Upon examination, the hard part of this is removing the driverside where the long hose snakes under the wiring harness and digs underneath the airbox breather tube. If anyone has any suggestions, or simply knows of a guide that covers this part of the process, it would be immensely appreciated!

[TisMe]

Luckily I just stumbled upon this video which, despite not being super detailed on the removal process, at least gives a visual inspection of what was removed to get there. It looks like this guy loosened his wire harness, removed his airbox breather tube, and also took off that T-hose that snakes underneath the manifold. Fingers crossed that's all that's needed to be removed to get enough clearance.

This also involves taking off another notorious banjo bolt, which reminds me that I should probably source a couple of those before I get started on this. Hoorah! I hear that you're toying with the karmic car gods if you reuse your banjo bolts.

Still open to any further tips or suggestions if they cross anyone's mind

[jkatz]

I bought the IPD kit for my ‘07 and it came with the long horizontal hose, both banjo bolts, and 4 new copper crush washers.

That hose looked like it would be hard to replace but it was pretty straightforward. Getting the banjo bolt into the intake manifold was the only part of the job that had me yelling profanities under the hood. I’m not proud of it but I probably spent 2 hours getting that one bolt seated.

[TisMe]

Here's an interesting notation from my current experience. I pulled off the oil trap last night, and it poured oil all over my engine and floor due to a large amount of oil being, as the name implies, trapped in the box. It was at least 3 fluid ounces. From all the videos I've seen, no one has had this much oil caught in there. I wonder if this has something to do with a clog somewhere, or perhaps the box malfunctioning in some way?

Despite that, my engine block was barely clogged. There was a small amount of sludge in the lower port, which my car surely will be happy is gone, but otherwise this may be chocked up to preventive maintenance. Mild bummer, as I was hoping there was back pressure that would be the prime candidate for my oil leak. Reconstruction will answer this quandary.