1997 S70 T5 Oil in the intake & smoke in the morning

Fosgate · Post by **Fosgate** » 28 Sep 2015, 08:18

Hey guys,

I was hoping someone could shed some light on this smoking issue I been having with my S70 T5 volvo (with around 190,000km on the clock) ever since I bought it. I have done less then 5000kms since buying it 4 years ago and replacing everything that I could think of which could cause this problem, including the PCV system with all the hoses, brand new turbo was installed 1000kms ago as well.
Basically whats happening is when I start the car in the morning it smokes for around 3-5 second and then everything clears up. This only happens 50% of the time and the amount of the smoke can vary from a small puff to not so big cloud.
So first thing I did was to replace the whole PCV system... but that didn't help, next thing I replaced the turbos core with another brand new unit and again no difference. I was beginning to suspect that it would be the stem seals and depending the position of the valve when I turn off the car it will determine if it will smoke in the morning or not.
However recently I had to replace the seal behind the cam angle sensor, and to make it easier I removed the plastic pipe going to the turbo and to my surprise I found quite a bit of oil in that plastic pipe... perhaps as much as a dining spoon full. So this tells me that the oil some how find its way into the intake piping before the turbos and gets sucks into the engine in the morning when I start the car.
The only way I can think of for the oil to find its way there is through the PCV system as there are two rubber hoses connect to that plastic pipe just before the turbo. However when I remove the deep stick I do not feel any air pressure coming out of the deep stick hole and it doesn't get pushed out under boost... which telling me that there isn't much blow by.
So I'm little lost should I go ahead and replace the stem seals? but if they are the issue why do I get oil in the intake pipe before the turbo?
I'm thinking of installing a catch can from the PCV system to see if the oil gets accumulate there and if the smoking stops and I think that will determine if I should go ahead with the stem seals replacement or not.

Any advise would be appreciated.

Post by **RussB** » 28 Sep 2015, 08:50

Valve guides are a likely suspect, as are turbo seals...or both! See if there is oil pooling up in the hose connected to the turbo

Fosgate · Post by **Fosgate** » 28 Sep 2015, 09:43

thanks for your reply, turbo is brand new, and there is around spoon full of oil in the pipe connected to the inlet of the turbo ...

Post by **FLXC90** » 28 Sep 2015, 17:03

Sounds like stem seals, the oil is not burning in a quantity large enough to notice smoke while driving, however, after shutdown, residual oil leaks down the valve and drips into cylinder, that's why it puffs on lightoff. I personally believe this is a big contributor to burnt valves in these motors.

Stem seals require removal of the cam cover and the cams, valve retainers and springs. Doable, but fiddly. It will probably take a day to a weekend depending on your tools and experience. (Precopster did a repair and showed tools he used recently)

I know a lot of people are down on chemical treatments, but I used a product called ATP-205 in my N/A S70 with 225k miles, and it cleaned up. The stuff allows dried seals to become more elastic again. May not work for you, but it was 20usd on amazon.

Post by **dosbricks** » 28 Sep 2015, 18:18

FLXC90 wrote: I know a lot of people are down on chemical treatments, but I used a product called ATP-205 in my N/A S70 with 225k miles, and it cleaned up. The stuff allows dried seals to become more elastic again. May not work for you, but it was 20usd on amazon.

Tomorrow I'm dosing our two NAs as a preventative or restorative measure--one oz. in the power steering and the rest in the crankcase. Your post confirms for me the wisdom of spending $20 to preserve an engine or steering rack. Thanks.

Fosgate · Post by **Fosgate** » 28 Sep 2015, 20:44

Sounds like stem seals, the oil is not burning in a quantity large enough to notice smoke while driving, however, after shutdown, residual oil leaks down the valve and drips into cylinder, that's why it puffs on lightoff. I personally believe this is a big contributor to burnt valves in these motors.

Stem seals require removal of the cam cover and the cams, valve retainers and springs. Doable, but fiddly. It will probably take a day to a weekend depending on your tools and experience. (Precopster did a repair and showed tools he used recently)

Yeah exactly what I been thinking but finding an oil in the intake piping makes me think that there is something with the PCV system that pushes oil into the intake piping .... I cant see any other way oil getting into the intake.

I wonder if the ATP-205 can be used in turbo engines? without causing more issues.

Post by **mecheng** » 29 Sep 2015, 09:32

I heard the ATP-205 is really good but can it destroy certain seals? I read that somewhere, can't remember which type of seals.

Post by **FLXC90** » 29 Sep 2015, 15:30

WARNING: Just found THIS on the web..."Yes, I FINALLY got a hold of their tech dept. and they told me it is a 'plasticizer' agent which only works on rubber/EPDM type seals, and actually EATS plastic/teflon/delrin?? type seals.*" from an oil forum user spoke with techs at mfg of ATP-205

How does it affect our vehicles..dunno which components have affected seals, don't know time line for problems.