98 V70 smoking dipstick test

[rmmagow]

Worst case if it is blocked and you need to put the job off for a while, pull the oil dipstick out a little ways and secure it in place so that the engine can vent off the pressure buildup. This will help save you from a blown rear main seal and cam seal.

[Klausc]

For the NA engine, there is a great post on the main page which shows replacement vacuum lines. Look it over.
If you have always used dino oil, that will contribute to cloggs. After you get vacuum, switch to synthetic and keep the engine cleaner.

I would first look at the PCV flame trap. Clean it up and throw away the small screen, then check for vacuum again. The small line from the flame trap goes over to #1 cylinder, it does clog easily, but that is just to reduce oil vapors from the top of the valve train and won't do much to increase vacuum - but clean is better.

[98v70dad]

Pulling the dipstick makes sense. Its obvious once its pointed out. Great suggestion.

I bought this car for a really good price and my daughter drives it at college. Unfortunately I often find maintenance issues and dont have time to get the parts and do the work before the car goes back to school.

[polskamafia mjl]

Everything you need to know is in the link erikv11 posted above.

- Use only OEM parts, dealer is cheaper than many online vendors, believe it or not.
- Oil Trap, clean it and re-use it
- Vent hose, don't waste $ on the Volvo part, get the 5/8-inch heater hose.

Again, review the link posted.

+1

cn90's heater hose idea is a must.

[98v70dad]

Yes,the 5/8 hose sounds like a good idea. I am planning something similar.

[98v70dad]

This is a fairly old thread I started and I've been thinking about the issue and have a question about this system. Why does the long hose have to be routed UNDER the manifold? Does the heat from the engine and manifold aid in the circulation or keep vapors from condensing in the hose or is the routing just because it makes the hose shorter or makes the engine compartment look "cleaner". It seems to me that you could route the hose on top of the manifold or some other easy route and completely avoid having to pull the manifold (I'm thinking roughly same route but right on top of the manifold). I don't really care what it looks like as long as it works ....keep in mind I don't have a car available to look at the moment so don't beat me up too bad if there's some obvious reason this won't work. Does anyone have any thoughts on this out of the box (manifold) idea?

[erikv11]

I've thought about this one before, and while the basic answer is I don't know, here's one thing I thought of: The long hose/pipe routes crankcase gases over to the intake at the throttle body. Even though it is warm in the hose, some of those vapors will condense as they pass through the pipe, that is one of its purposes. That direct route under the manifold could be to maximize the chance for oil vapors that condense in the hose to drain back into the trap, instead of draining into the hose at the throttle body. With the OEM design the hose is basically "all uphill" until it meets the throttle body. If you instead take a long hose and curve it up and over the manifold, then you may get more draining of condensate into the intake. Just a thought. I doubt it would be much of an issue if you took an alternate route.

Also, up and over the manifold will require some bending through different angles, more of a hassle. Note that the OEM pipe is just that, a hard plastic pipe, that doesn't bend at all.

[cn90]

Just the location of the oil trap and the Intake Pipe are far apart in the Volvo 850, S/V70 series.

In my 2007 Honda Odyssey, the PCV hose is about 2" long and that is it.
My previous 1983 BMW 735i has a PCV that is 3" long and that is all.

Modern engineers complicate things quite a bit!

[erikv11]

Yeah, the distance on the 850 is longer, for whatever reason.

So given that, any thoughts on the question at hand, i.e. is there a best route for the hose between them?

[98v70dad]

Modern engineers ( I am one myself, although I'm over 50) are forced to do stupid things by business managers either to save a few cents per unit or to accommodate the marketing people. I agree that any alternate route you might use should have the pipe sloped toward the trap. I also agree that the tube is ridiculously long.... stupidly long, but we're sort of stuck with that. It just occurred to me the other day that maybe there is a much easier alternate route that would eliminate removing the manifold. It may not be a practical idea just from the standpoint of access ... don't know. Removing the manifold probably greatly improves the access to the trap and all the connections that need to be made. I've also considered that the long tube could be approximated by using two L-shaped 5/8 diameter heater hoses spliced together at the middle. Unfortunately I won't have the car to look at until my Daughter's Christmas break from school.