Top of my engine is dry bone, no stains till the level of the oil filter.
Valve cover has no leak (2 years old).
But on the garage I always found a little oil drop after long trips.
I tried to look under the car by the side, I found some exudations on the oil pan cap and nearby, some on the (I think) overdrive assembly.

You can see leaks on the videos below:
https://youtu.be/1JkOZsMNt_0
https://youtu.be/_eZaN8_dpbI

I've never put 244 on jackstand but I'm planning to do so to clean carefully it and see better where it leaks. Someone can guide me where to look closely for leaks, or pinpoint weakest parts that can leak on red blocks?
244 B19A, 1981, 107'000km.

I suspect rear main seal but I have some oil before it, so when I'll clean it I'd like to focus on the right spots.

Someone suggested PCV valve and flame trap... but does my car have it? Seeing some vids on youtube and the spare parts on various sites I can't find something similiar in the engine, except for this plastic black part.

https://ibb.co/YFvJggPc
https://ibb.co/7tL9Nw59

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1981 244GL - B19A engine

If all you get is an occasional drop of oil on the driveway then that's not too bad for a 44 year old red block, even one with an amazingly low 100K km on it.

From your pics and videos, it's hard to guess the source, but there are of course likely candidates and there may well be multiple points where oil is weeping, including the oil pan gasket. Maybe go around and snug up the accessible oil pan bolts, but not so tight that you warp the pan lip (check the torque spec and maybe go a couple of ft-lbs higher).

Odds are high the rear main seal is one source. If there's any positive crankcase pressure then oil can push out around the engine seals. Drips of oil collecting at the opening in the bottom of the bell housing is the classic symptom of the rear main seal and if it's red oil then the trans bushing/seal is weeping. You say the valve cover gasket isn't leaking, but please double check the area below the valve cover at the back of the block. There's a half-moon plastic plug there than can sometimes weep if the valve cover gasket isn't nice and snug back there. If it is the rear main seal then consider switching to a high mileage oil. High mileage oils have seal conditioners as their main additive to help pucker a worn seal. Problem with oil conditioners is that they will also pucker the front seals, which will help them wear out a little faster, but they're relatively easy to replace, so it's usually worth the tradeoff rather than having to drop trans to get at the rear main seal. Even if they're not leaking, consider replacing all three front engine seals with every new t-belt. At your age and mileage, a seal conditioner would likely be beneficial. I'm still on the original main seals on both my red-blocks with over 400K km on them. Both have been weeping for many years, but I've managed to keep it down to a tolerable level by occasionally using a high mileage oil with a seal conditioner.

The front oil seals are usually the most obvious sign of a plugged PCV system. Oil can drip down behind the timing belt cover and get blown back under the engine and allow oily, black residue to collect all over the place, even as far
back as the bell housing. It may not be obvious that's where it's coming from.

Every time you do an oil filter change or even even when filling and spill oil on the valve cover, oil can easily drip down and collect in odd corners under the engine and around the engine mounts. If the oil pressure sensor wire gets caught behind the oil filter then it can really leak. It's also possible the oil filter isn't snugged down tight enough to make a good seal. Last oil change I did I must have had oily gloves on and didn't do a good enough job of hand tightening the filter, so got a tiny bit of weepage there that took me a couple of weeks to notice.

With yours, I'd start by doing two things:

First, clean all the oily residue under the engine as best you can. Over the coming days and weeks you'll then be able to see where the fresh oil is collecting and coming from. Use spray engine cleaner (be generous, do it on a warm engine, lots of newspapers on the ground to catch the mess), a toothbrush, wipe reasonably clean with rags/paper towels, then rinse it down with a hose and (soapy) water when you're done. Once it's dry you'll be able to notice where fresh oil is coming from. Realize that driving will blow oil backwards under the engine, especially if the belly pan is off, so check for leaks sooner rather than later.

Second is to inspect and clean the crankcase ventilation system. With the engine running, remove the oil filler cap and place a thin rubber glove (or something similar) over the filler neck. If the glove sucks down, the PCV system is working okay. If it puckers, the system is plugged and likely pushing oil out past the engine seals and even the oil pan and valve cover gaskets. If it stays flat then it may be partially plugged. In any case you should remove the main crankcase hoses and inspect the nipple areas and even blow into the ends to make sure the nipples aren't clogged.

Near as I can tell, your B19A has a hose between the air intake tube and the valve cover (middle of the top or side at the front of the cover). There's a nipple at the air intake tube you should open and check. It's not likely blocked, but there may be oily residue condensing in the air intake tube that you may want to clean out so it doesn't collect up at the carbs.

That black box you pictured is the oil separator box on the block. The nipples can get caked with oil and slowly start to plug, but at your low mileage I think that's unlikely. It would still be worth checking by removing the oil filler cap then blowing through the hose back down through the separator box to make sure it isn't blocked. You can even remove the hose from the top of the box and poke a small screwdriver or drill bit around to loosen any caking inside the top nipple. Checking the bottom port requires removing the box -not worth the effort unless you run out of ideas and suspect it may be blocked,

I'm not so sure your B19A has a flame trap like the later B20/B21/B23/B230 OHV red blocks. If not then it may have a PCV valve. I can't see either one in the B19A schematics I'm looking at. If present, they will be found inline at the top of the hose off the oil separator box. If present, remove them and inspect to make sure they're not blocked. Clean and/or replace as needed. If it happens to have the original coiled brass flametrap element, those can more easily get plugged, so replace it with a newer style plastic one with holes in it.

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Dave -still with 940's, prev 740/240/140/120 You'd think I'd have learned by now

Thanks for your response!
Sorry if I'm boring but I would like to ask you for a minute of your time to understand if I have understood some technical terms that I struggle to translate into Italian. the little drop I see is in the garage, where the car sits for 2-3 weeks usually. So yes, very little drop but being a garage queen if possible, I'd like to solve. I'm quite sure the oil separator is the original 1981 one.


- The PCV and the "black box" I showed, are different things? I honestly tought were the same part. Anyway, the black box is on the way to be changed with a brand new one+new oring.

- I have the copper flame trap that is just over it (see the position there: https://ibb.co/0jBR7ymf) has been accurately cleaned, waiting to be installed back.

- at the center of the ait intakes there are 2 hoses: one going to the side of the distributor and one is going to the oil separator (I think). talking about these? See in picture... https://i.ibb.co/dsVLB95B/20250303-184714.jpg

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1981 244GL - B19A engine

The PCV is not a single component, it's the whole system. The black box on the side of the block is the oil separator and the first part of the PCV (positive crankcase ventilation) system. The old one is likely to be rather stuck and brittle, so be a bit careful and if you break the neck off don't let pieces fall down into the crankcase.

I gather from your comments you did find a flametrap element located just above the separator box in the base of the rubber hose connected to it. In the schematics I was looking for it at the other end of the hose. Checking and cleaning that element should become part of your routine maintenance, at least every second oil change (or even every oil change if you find it gets dirty). The original style coil metal elements can be a pain to clean if they get caked.

Your PCV hoses seem a bit different from what I see in the Volvo parts schematic diagrams (which may be for an older B19 engine), but the principles are the same. I was editing my post, so make sure you go back and read my additional comments about oil leaks and seal conditioners compared to the initial automated reply that you received from the Brickboard system. Composing and editing long posts here can be a pain in that regard.
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Dave -still with 940's, prev 740/240/140/120 You'd think I'd have learned by now

thanks, yes I did read the whole post, thank you again :)

I've read a lot of times "PCV maintenance" and "flame trap maintenace" in youtube videos about 240, and that caused me that confusion.

So...generally speaking apart from flame trap and Oil Separator (yes, I gave for granted it'll be brittle...) your suggestion is in the end to check all hoses around for integrity and maybe obstructions/oil gunk :D
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1981 244GL - B19A engine

One more thought. Just remembered that I stopped my rear main seal from leaking after replacing the flame trap, its hoses and cleaned the oil separator (also called the Breather Box). That fixed the clog in the PCV system which relieved the excess pressure put on the RMS by a clogged PCV system. Truly Amazing!!

The leaky oil pressure switch came later. That was a minor leak.

Thanks, is what I'm hoping it'll do.
The copper filter was not completely clogged (maybe half), but the breather I don't know in what state is. In any case, being 44years old a refresh is to be done.

About the oil pressure switch I have to put car on ramp to clean all accurately and reach it to see ;)
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1981 244GL - B19A engine

If your engine has one, the flame trap is on top of the engine near the intake manifold. Another pollution control part “the breather box” can also leak if clogged. A hose connects the flame trap to the breather box.

If the oil pressure switch is leaking (a minor leak) it will drip down near the oil filter. It screws into the block. Easy fix!

Rear main seal leaks usually show up where the transmission bolts up to the engine. My 90 240 had a slow RMS leak which never required replacement. Thank God! No one wants to pull a transmission just to replace a RMS seal.

Thank you!

The previous days (while brickboard was down, as happens frequently...) reading some forums I located my flame trap, is in copper and directly connected to the breather valve, as you can see in the pic above. Sadly the img uploader don't works, so I used an external service:

[url=https://ibb.co/0jBR7ymf][img]https://i.ibb.co/0jBR7ymf/500799390-10233158998412008-3289989402086678080-n.jpg[/img][/url]


I cleaned the copper filter very well, and I ordered a new PCV assembly + oring, because I don't think it has ever changed so let's see if it will improve. Do I need to check for the hoses too?

For the the oil pressure switch: can you help me locate it?

Rear main seal is my main concern, due to fact that a little drop is directly on one of the bolt: we're talking of a very little drop but I want to investigate more.

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1981 244GL - B19A engine

Hi,

Check the condition of the PCV hoses. Look for very soft, oily or dry crumbly hoses. Particularly check the hose that runs from Flame trap to the Breather Box (look under manifold). The Breather Box can also clog after many miles/km. The other hose should run from the intake manifold to the Flame Trap. However, not sure if the layout of the hoses on your car is the same as on my 90 240DL (b230f engine)??

The oil pressure switch is screwed into the side of the engine block on the passenger side above the oil filter. If leaking replace. Easy job with the correct wrench!

Good luck,
JW

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Will I buy another Volvo??? We'll see....

thank you!
next week or so I'll have my brand new pcv and oring and I will install it.
Hoses are, externally, perfect (107.000km) but are obviously 44 years old.
I'll look at them closely. They seem common automotive hose, if I can find them I'll change them anyway.

I think I understood where's the oil pressure sensor but I think that if it is leaking, worth wait for an oil service to avoid oil spewing everywhere?
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1981 244GL - B19A engine

If the engine is not running there is no oil pressure, hence there is no danger of, "oil spewing everywhere."

You may lose a tiny bit of residual oil from the gallery when you remove the sensor. Wait until the engine is cold and this will be negligible.


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'79 242, '84 DL 2 door, '80 DL 2 door, '89 DL Wagon, '15 XC70 T6 AWD

I tought the sensor being in the oil pan could be under the oil pan level. In that case, if leaking I'll change it :)

Do you have a torque indication for it?
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1981 244GL - B19A engine

The oil sensor isn't a fluid level sensor, it's a pressure sensor that confirms there's both oil in the system and that the oil pump is working. The oil level has to be way below the end of the dipstick before the pump sucks air and trips the sensor, first noticed when driving around a corner at speed. It's mid-block height below the exhaust manifold and well above the oil pan. Oil won't come pouring out when you remove it. If the engine has had a chance to sit you won't even get a dribble.

I don't see a torque spec in the Volvo Pocket Data Book for the oil pressure sensor. The spec for the block temp sensor is 30 ft-lbs, which is a similar size thread in the block, so that's what I'd go with and do it with a cold block. Good and snug is really all that's needed.

Unless it's damaged or has been previously removed then the odds of an oil leak there are slim, but if there's oil grunge below it then clean around it and check it after a few days of driving just to be sure.

If it is leaking then removal and cleaning the threads and mating surfaces would be in order rather than overtightening it. Do not use PTFE plumbing tape as the threads provide electrical ground for the sensor. Do not use anti-seize as it's not meant to be a routine service item and come out easily, plus torque specs are always for clean, dry threads unless specifically noted otherwise.

As a bonus oil leak thought here, I'll mention the oil pan drain plug. Although yours looks dry, it's a common area for minor oil weeping. The copper washer is a crush washer. The torque spec to crush it evenly is 28 ft-lbs. Dealer service is supposed to replace it with every oil change to assure a good seal. The washers are cheap and can be had almost anywhere you buy filters (just note it's a metric size and thicker than a steel washer). If you don't have a new one then rather than risk overtightening it and stripping the threads, another option is to re-soften the copper by annealing it, heating it up with a torch until it starts to change color and turn pink then quench in water. You can keep that game up for many years until the washer gets thin.
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Dave -still with 940's, prev 740/240/140/120 You'd think I'd have learned by now

I replaced my oil pressure switch a very long time ago. I don't remember if you can replace it with an engine full of oil? Maybe?? To play it safe, it is probably wise to replace it when the engine is empty of oil.

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Will I buy another Volvo??? We'll see....