1997 850 Problems after Change to Synthetic Oil

[plumsmooth]

That's the second tech at Volvo dealership that recommend against switching an old car like mine over pcv overhaul aside.

The tech said pcv condition aside that seals can leak after switching to Synthetic...

Whats puzzling right now is that aside from the $750 Pcv quote which is about what I expected, the service tech I just spoke with said depending on how plugged with sludge etc. that an additional 4 hours might be needed to remove oil pan and get sludge out of there?

I haven't heard anyone here, even through the tutorials, mention this part of the project.
Unless I didn't read through throughly...

That would be 1,150 dollars I don't have...

[cn90]

Tons of PCV DIYs in forum, you can search for them.

[mecheng]

If you did regular oil changes and take the car on the highway once in a while you should not have any sludge. If you are concerned, before you change your oil run 1L of auto trans fluid through the engine for 10min and then change the oil. I did for peace of mind and it worked well as you can never be certain how the original owner took care of the car.

Don't waste your time opening up the pan, take care of the PCV first!

[mika]

How about draining and refilling with some dino? I would go for something thick like 20w50 if climate is not an issue. What is there to loose? Easy to do by yourself. Skip the mechanic from now on! start going over PCV step by step over the next few weeks/months and see if it even needs to be serviced.

[mika]

If you did regular oil changes and take the car on the highway once in a while you should not have any sludge. If you are concerned, before you change your oil run 1L of auto trans fluid through the engine for 10min and then change the oil. I did for peace of mind and it worked well as you can never be certain how the original owner took care of the car.

Don't waste your time opening up the pan, take care of the PCV first!

Can you elaborate on your reasoning behind ATF before an oil change?

[precopster]

Seals fail all day long. You would need the results of a controlled test on many hundreds of vehicles conducted over many years to even be able to comment on the effectiveness or otherwise of dino or synthetic.

I've never seen NEW or even 5 year old GENUINE seals leak on a Volvo regardless of oil used.

The tech at Volvo conceded one thing that is for certain. If you run dino oils and DON'T HAVE OIL CHANGED REGULARLY your sump can have sludge buildup which can block the oil pickup screen. Symptoms on your 850 would be loud tapping noises on the valve lifters as they are hydraulic. If oils have been regularly replaced you need not fear about sludge. If your lifters are noisy you can also have a cracked o ring seal on rhe sump but that's another chapter in this conversation.

[dosbricks]

Whats puzzling right now is that aside from the $750 Pcv quote which is about what I expected, the service tech I just spoke with said depending on how plugged with sludge etc. that an additional 4 hours might be needed to remove oil pan and get sludge out of there?

I haven't heard anyone here, even through the tutorials, mention this part of the project.
Unless I didn't read through throughly....

There are a couple of threads about this buried somewhere in the archives. As Mike says, it's rare, and would only happen in an extreme case of sludge buildup--such as when cheap engine oil (lots of paraffin) was used and not changed for long periods.

There is an oil return passage from the oil trap back into the block that is a cast tunnel down the inside of the block and mated to the same inside the oil pan. It delivers the condensate oil back to the bottom of the crankcase rather than at the side of the block where the crank is splashing oil at a rate we likely can't imagine. So long story short--you probably don't need to worry about it.

P.S. the test of this--and something which, IMHO, should always be done during a PCV job--is to attach a heater hose onto the nipple on the side of the block and blow through it. If you hear air bubbling up through the oil in the crankcase, then no problem.

[mecheng]

If you did regular oil changes and take the car on the highway once in a while you should not have any sludge. If you are concerned, before you change your oil run 1L of auto trans fluid through the engine for 10min and then change the oil. I did for peace of mind and it worked well as you can never be certain how the original owner took care of the car.

Don't waste your time opening up the pan, take care of the PCV first!

Can you elaborate on your reasoning behind ATF before an oil change?

It is high in detergents to clean sludge but less harmful than flush solutions with solvents as trans fluid is
Designed to work with rubber seals. Do it once or twice, not every oil change

[FLXC90]

+1 for Dos' last post;
Since you have not done PCV yet, I assume that is not your breather box in the pics. That motor was sludged.
Oil vapor under pressure from the crankcase is drawn into the box, where the oil settles to the bottom and is supposed to drain back into the oil pan. the air is drawn out to the intake manifold to relieve pressure, and control the emissions that would result if the oil just spewed out into the atmosphere. (there's your theory on how it works) As oil is exposed to engine heat and the gasses from combustion, it loses its ability to lubricate, then it will start to thicken and turn to sludge (that's why we change oil) If the oil plugs the bottom passage from the oil box (think of the picture), then the air will continue upward, and the oil won't settle out of it. It doesn't flow as well back to the sump and intake manifold, this increases pressure inside the motor. If it were elastic, it could swell like your chest, instead, the pressure looks for other ways to escape. The plastic/rubber used to make the seals deteriorates from time and heat also. Dried seals tend to shrink (minute amounts) and can become "loose", the rear cam seals are usually the first to go on these engines, and that's good, because they are really easy to change. So, read the tutorials, spend 100 bucks on tools, another 100 on parts, find a friend who can wrench a little (Does not need to be a pro mechanic, just enough to encourage and guide you-the forum will do the rest) And do this stuff. It will take you a full day to do the PCV probably, then about an hour to change both cam seals. Then you can drive with a LOT more confidence, and enjoy your Volvo.

(sorry for the book!)

Otherwise, take it to the shop next town over-the Chevy mechanic is not doing you any favors. he could change the seal under the distributor in about 15 minutes most likely!

[FLXC90]

Oh yeah, remember, when you see all the "problems" people discuss here, they aren't telling you the other side of it, like "I drove for x years before anything went wrong" and most importantly; this forum is solution oriented, not just for ourselves, but for each other.