Did I Pass The "Tea Kettle" Blowby Test? And How Does The Engine Sound?
 

This morning I decided to try out the "tea kettle" blowby test on my 1980 W116 300SD. The oil cap didn't fly off, so that's good. It actually just sat there on the valve cover. When I removed the cap, I couldn't see any smoke coming out at all.

I did the test with the engine cold. Is this the proper way to do it, or should I have done the test with the engine hot? Also, does the engine sound like it idles fine? No injector nailing or anything? The engine has over 315,000 miles. I use Amsoil Synthetic 15W40 Heavy Duty Diesel & Marine Oil and B99 biodiesel year-round (thankfully, it's cheaper than diesel).

Here is the video: 300sdblowby - YouTube

You have no blowby. It's hard to believe it has 315k on it. How did you get the wood surround on the instrument cluster?

This is great to read! I have worried since it was a cheap, beat-up, high mileage junker car when I bought it. The engine seemed to be the strongest point and it never seems to smoke out the exhaust pipe.

The wood was an expensive $400 eBay Deutschland purchase from http://www.eris-car.de.

I wouldn't pay $400 for it but it looks very nice. Are you sure the engine hasn't been replaced. I've looked at some 200k engines which smoked like a steam locomotive.

The engine hasn't been replaced, that I'm aware of. The past few owners neglected the vehicle, and I have no receipts older than the 1990s.

Not to rain on your parade but I tend to think common sense will say that the motor has been replaced or rebuilt at some point. Either that or whomever put the bulk of the mileage onto it, ran it on the highway exclusively and did frequent oil changes. Even that would be a maybe for me, at 315k.

My 300d just turned over 100k and it has a little smoke out the filler.

My first 300sd (w116) had about 80-100k on it after an extensive rebuild, when I purchased it, and it smoked a little bit.

I did buy a parts car at one time from Boston that had around 300k miles on it and had exceptionally little blowby for the mileage, but it still had evident blowby.

"I tend to think the motor has been replaced or rebuilt at some point." I would think that would be a good thing!

The reversed oil cooler attachment bolts suggest someone pulled the oil cooler at one point. Perhaps to swap an engine??

That is disappointing. :(

Just kidding. Well, if the engine was rebuilt, that is great. I have no proof that it was, but if so then maybe I didn't overpay afterall. Everything else about the car was trashed and worn out (transmission, steering, brakes, doors, interior, electrical). I am having a front crank seal and oil tower leak that I need to fix.

I don't think the oil cooler bolts are reversed. All the ones I have seen slide from the front of the car toward the back, making removing the oil cooler by itself difficult. I don't think it's possible to slide the bolts in from the back to the front, and the nuts would never go on the condenser side. At least this is what I remember from my last 300SD and the others I have taken parts from.

Also, I will check the engine serial number to see if it matches the build sheet. Then, at least I will know if it's the original engine.

My 83 300D T with 297k with the original engine has no blowby. The garbage bag blow by test did not inflate after 10 minutes and I gave up with the test. Inside of the air cleaner housing is totally dry.