96 850 Non Turbo. PCV System and Emissions

[tourspin69]

Getting my "new" 850 into shape little by little. Car only has 75K on it. Brakes, Tires, timing belt etc.. So now I have another issue. Fumes in the car and not passing NY State emissions. The exhaust no doubt is on it's last leg I think, but that's not where the fumes are coming from. Could be a leak in my Manifold, or somewhere up front. Anyway...I have just followed the direction of some of the posts regarding clogged PCV and I failed the first test which is smoke coming out of the dipstick.

My question here is...I know that I should replace the entire system, however I am out of cash for this project right now. Is there a hose or some lines/hoses that I can clean or replace without replacing the entire system?

[rspi]

You can pull and toss the flame trap out if it is clogged. Other than that, most of it is so brittle it will break into pieces if you mess with it to much.

[tourspin69]

Just found the vacuum line on the side of the intake manifold is completely broken off!! If I replace, will this help things? or is the system likely clogged anyway?

[rspi]

That is often the cause of the smoking dip stick. Sure, replace it and see if that cures your problems.

[dosbricks]

On edit: While I was typing, Robert just posted his video which will tell you all you need to know.

With only 75k on it, and if the former owner used high quality detergent oil, the system might be OK, but if those miles were all cold-start short-trip then the PCV is likely due to be replaced. Good luck.

[tourspin69]

Thank you. I think the hose is Volvo #9155862. However, I'm not sure how the hose connects. I can see where it fits over the nipple on the manifold, but it looks like the other side is a female where the line feeds into the new connector hose? Do I need to follow it down to the breather box?

[erikv11]

To replace the vacuum line, which is definitely worth it, you want to just get generic rubber vacuum line. I am pretty sure it is 3/16. One end on the nipple, the other end on a little plastic nipple on the flame trap housing, over near the throttle body. Under the distributor cap. You can route the hose whatever way works for you, it doesn't have to go under the intake manifold but that route works pretty well.

The vac line may help a great deal but: Yes you can probably clean out the entire PCV system, it is not recommended but I have done it before. Especially with the low miles on this car it is probably fine. Here are some comments to help you decide and consider possible expenses if you choose to open it up:

(1) Almost every oil trap I have ever taken off could be cleaned and re-eused, these almost never break.
(2) Be very careful with the two short rubber hoses that connect the oil trap to the block. These will be hardened and/or mushy and difficult to re-use. If they get trashed, you will want to buy Volvo brand parts. Or cheapies but then you have to go back in there within the next year and replace them with good ones.
(3) The thin vacuum line from the intake nipple to the flame trap you will want to replace anyway. Use generic rubber vacuum line.
(4) The long pipe from the oil trap to the flame trap housing is likely clogged up and may be brittle, it is uncommon to be able to re-use this part but your car has low mileage so that is a plus. You never know until you get in there, I have seen them be wide open and easily cleaned out. But if it needs replacing, you can simply use 5/8 fuel line (about $10), look for write-ups on here. You have to be careful with the 5/8 but if you are, it works really well.
(5) The main reason this is worth checking even if you can't buy the new parts is to *thoroughly* clean out the ports from the oil trap into the engine block.
(6) Don't forget, you will need to buy an intake manifold gasket if you do this. And there is some expense for products to clean out the oil trap and hoses, and for some hose clamps.

[tourspin69]

Thanks guys. I am taking this all in. However, I need to do one simple thing that is turning out not to be that simple. I just want to replace the vacuum hose on the passenger side of the manifold. However, it's proving to be very hard to access. I was able to remove the old hose. Now I need to figure out a way to attach the new hose to the manifold as well as to the existing line. Any suggestions on how to do this?

[dosbricks]

By hose I assume you mean the rubber elbow. It's a pita. You are working on one of the most frustrating things I've come across on an 850. Hook the elbow to the hard plastic line under the manifold first. But being old, it will possibly crush if you try to hold it with pliers. The other end of that black plastic tube connects to the small rubber nipple on the flame trap at the other end of the manifold. But, given it's position on the left side, it's nearly impossible to get a decent grip on it with fingers. This is why many folks reroute the line over the top of the manifold. It might be best to just do that temporarily until you can test whether this fixes your PCV issue or whether you have to replace the PCV system. BTW, the purpose of this little line is to assist the PCV system to pull a vacuum on the crankcase while dropping most oil residue off at the flame trap.

[erikv11]

Drain some coolant and remove the upper radiator hose. You can drain it out the petcock on the radiator but be *very* careful because if that plastic petcock breaks you will be cursing for weeks. ANd need a new radiator. Just open and close it gently, closing it only hand tight is more than enough. Then, get some very long nose pliers and use those on the hose at the nipple.

+1 to dosbricks, that is good advice. I prefer to use a length of hose and run it over the front of the manifold, it is just easier overall. You only have to struggle once at the intake manifold nipple area. That is my number (3) above and in the very beginning of that post.