After not being able to figure out where the oil leak(s) are coming from I took it in to a MB shop.

They checked it out and are pretty certain I have some serious blowby.

The mech. said that he removed the top vent tube on the valve cover, stuck his thumb over the hole and oil started coming out of the dip stick and just about every where else it could come out of.

So what do you guys think?

Do a compression test to check, maybe get an idea if this is what it is?

I don't have time to do a rebuild.

And just for fun, know of any modern MB IL4's that would fit in there?

__________________
Sold, but not forgotten:
1964 Ford F-100 "Maybelline" miss her
1960 Ford Falcon Ranchero
2 - 60's Econoline Scooby vans
1965 Plymouth Belvedere II, also missed
Currently:
1971 220
1980 Honda CR250
1973 Yamaha DT-250
2003 SV-650
2000 Honda Odyssey

and waaay too many motorcycles to list here

m102 (4cyl)
M103 (6)
M104 DOHC 6
you will have to use the trannies from these engines I believe if you swap, starter on opposite side and some other differences.

otherwise,
M130
M180
M110
all 6's
or another m115

or diesels om616.617,621

do a compression test, let us know the results, hopefully its not too bad.

__________________
____________________________
R107.043 Euro 350SL (parts)(crushed)
W116.024 280se (crushed)
W114 280 (m110)
W108.067 280se 4.5
W108.068 280seL 4.5 (crushed)
W111 220SEB coupe
W110 200D went to the crusher
W110 190D sold sold sold

1970 Rover P6B

Used to own(1950 buick,1969 lincoln MK3,4G63t colt,87 300ZX, 79 F100, 92 XJ40)

yup , compression test

__________________
Ron
2015 Porsche Cayman - Elizabeth
2011 Porsche Cayman - Bond,James Bond
Sadly MERCEDESLESS - ALways LOOKING !
99 E320 THE Queen Mary - SOLD
62 220b - Dolly - Finally my Finny! Sadly SOLD
72 450SL, Pearl-SOLD
16 F350 6.7 Diesel -THOR
19 BMW X5 - Heaven on Wheels
14 38HP John Deere 3038E Tractor -Mean Green
84 300SD, Benjamin -SOLD
71 220 - W115-Libby ( my first love) -SOLD
73 280 - W114 "Organspende" Rest in Peace
81 380 SL - Rest in Peace

The familiar compression pressure test, i.e., pressure gauge screwed into spark plug hole, crank engine, read gauge, will provide you with some information about the sealing of the rings and valves.

A leakdown test will provide more information. Cylinder by cylinder, air pressure is applied with the piston at TDC, and the difference between the line pressure, and the pressure held in the cylinder, is observed. By listening, one can determine whether it is valve and/or stem leakage, or ring leakage.

That is more or less normal for any engine. That is why you have a engine vent.

The M115's are pretty rock solid. Their only weak points I have found with them are valve guides and valve seals.

The problem with the guides only seem to occurs after a severe overheating issue. Does there seem to be a "rattle" in the exhaust with a quick release of the accelerator linkage? I call it the "MG mumble" in reference to the wonderful sound those old MG engines make as you run them though gear changes.

The M115's are vented directly to the intake manifold. Check the manifold fitting for obstruction. When the engine is running there should be constant vacuum to the valve cover. There is an oil trap inside the cover to prevent oil from being sucked through the line.

__________________
“Whatever story you're telling, it will be more interesting if, at the end you add, "and then everything burst into flames.”
― Brian P. Cleary, You Oughta Know By Now

That is indeed normal. On my Jeep, the one vent tube became clogged and I had oil leaking out my dipstick. That was 30k miles ago. Still runs fine. Yeah, it has some blowby, but nothing I'd consider major, and it uses maybe a quart every 2k. It's way more likely valve stems and/or seals.

__________________
Current:
2021 Charger Scat Pack Widebody "Sinabee"
2018 Durango R/T

Previous:
1972 280SE 4.5
2014 Jeep Grand Cherokee Limited "Hefe", 1992 Jeep Cherokee Laredo "Jeepy", 2006 Charger R/T "Hemi"
1999 Chrysler 300M - RIP @ 221k

thanks for the info, I'll be doing a compression test today and I'll check the vent hose all the way to the air filter. If that prove inconclusive than I will probably move on to a leak down test.

This all started because I can't figure out where the leaks are coming from, oil all over the place and uses a lot more than a quart every 2k and makes a huge mess on the garage floor or wherever it is parked.

__________________
Sold, but not forgotten:
1964 Ford F-100 "Maybelline" miss her
1960 Ford Falcon Ranchero
2 - 60's Econoline Scooby vans
1965 Plymouth Belvedere II, also missed
Currently:
1971 220
1980 Honda CR250
1973 Yamaha DT-250
2003 SV-650
2000 Honda Odyssey

and waaay too many motorcycles to list here

If you have oil leaks, clean the engine (as far as is possible) and watch for leaks. Put a large piece of cardboard under the car, so you see where it leaked.

I don't know if it is already winter in Portland OR, but if it is, sometimes the sludge collector in the engine vent can freeze, (partially) blocking the vent.

Finally had a chance to check compression today.
Starting at the front of the motor:
Cyl. 1 - 120
Cyl. 2 - 118/119
Cyl. 3 - 118/119
Cyl. 4 - 120

What do you guys think? I;m not sure what these should be.

@Govert- I've cleaned and tried what you suggested, it only wants to leak while moving(?) and the oil gets all thrown around and drips off the motor once it's in the garage.

and Happy New Year everybody!!

__________________
Sold, but not forgotten:
1964 Ford F-100 "Maybelline" miss her
1960 Ford Falcon Ranchero
2 - 60's Econoline Scooby vans
1965 Plymouth Belvedere II, also missed
Currently:
1971 220
1980 Honda CR250
1973 Yamaha DT-250
2003 SV-650
2000 Honda Odyssey

and waaay too many motorcycles to list here

The main thing you are looking for is consistency. You want the lowest reading to be within 80% of the highest. The numbers you are showing all appear to be a low but consistent. All compression gauges are different so it's a bit tricky to get the exact readings stated in manuals.

Do a cold test, a hot test and then do a test where you add a bit of oil into the cylinder. The readings should change but still remain within the 80% range.

The "leak-down" test Frank recommended will give you a more definitive reading of the condition of the piston rings but the standard compression test does a "quick and dirty" view.

__________________
“Whatever story you're telling, it will be more interesting if, at the end you add, "and then everything burst into flames.”
― Brian P. Cleary, You Oughta Know By Now

does seem low.. need a min of 90 to fire a cylinder... to give you some kinda reference point... so they're a little worn... I dunno its really up to you.. I'd really like to have a diesel again... they seem pretty consistent though. its normal to have 2 cylinders (middle) a little low at least in my experience.. if they were good, I'd say about 150-160psi per cylinder depending on C/R.

__________________
____________________________
R107.043 Euro 350SL (parts)(crushed)
W116.024 280se (crushed)
W114 280 (m110)
W108.067 280se 4.5
W108.068 280seL 4.5 (crushed)
W111 220SEB coupe
W110 200D went to the crusher
W110 190D sold sold sold

1970 Rover P6B

Used to own(1950 buick,1969 lincoln MK3,4G63t colt,87 300ZX, 79 F100, 92 XJ40)

Adjust the valves. This can cure many sins.

__________________
1968 230S Automatic, Elfenbein
1975 O309D Executive Westfalia Camper Bus, Blau/ Weiss
1972 280SEL 4,5 Dunkelrot
1966 VW Type 34 "Grosser" Karmann-Ghia
1963 VW 1500 Variant Pearlweiss
1969 VW Variant Automatic, Perugruen
1971 VW Squareback Automatic, Clementine Orange
2001 E320 4Matic Wagon- Our belated welcome to the 21st century! Polar White
1973 280SEL 4,5 Sliding Roof "The Bomb", Dunkelblau.

I haven't done the valves, and who knows if they have ever been done. On the list!

all the spark plugs, recently replaced, looked good, although the rear most, #4, was a little black.

I caved in to boring modern technology and got a Tundra to drive. I was driving the MB everyday as my only car and it made it really hard to work on it and make it to work the next morning. And, well, the Tundra is pretty sweet - my own belated welcome to the 21st century!

__________________
Sold, but not forgotten:
1964 Ford F-100 "Maybelline" miss her
1960 Ford Falcon Ranchero
2 - 60's Econoline Scooby vans
1965 Plymouth Belvedere II, also missed
Currently:
1971 220
1980 Honda CR250
1973 Yamaha DT-250
2003 SV-650
2000 Honda Odyssey

and waaay too many motorcycles to list here

Really, adjust those valves, run on them a few days and recheck compression, you won't be sorry. Just do it! Does not take long either.

__________________
1969
Model 220 gasoline
Chassis: W115.010