B100 cause blue smoke? - PeachParts Mercedes-Benz Forum

JWJ · #1 12-03-2006, 03:33 AM

My '83 MB 300D has a little blue smoke from the exhaust when accelerating right after a cold start-up. Once the engine warms up the blue smoke disappears. The car has >366,000 miles on the engine. I have a few slight oil leaks coming from the oil pan, etc. that need to be addressed but oil comsumption doesn't appear out of the ordinary.

Would using B100 cause the car to exhibit blue smoke more?

#2 12-03-2006, 05:33 AM

Valve stem seals and/or worn turbo seals. As the engine warms, they expand and fill the gaps.

JWJ · #3 12-03-2006, 07:16 AM

Thanks!

How do I determine between the problem being valve stem seals or worn turbo seals?

aklim · #4 12-03-2006, 08:10 AM

I thought valve stem seals are only puffing blue smoke on startup?

I'd take out the pipes to the turbo and check the shaft for endplay. See if you can rock the impeller and make it move. I am thinking that it is your turbo.

B100 shouldn't cause that sorta thing unless you got some bad biodiesel.

Knightrider966 · #5 12-03-2006, 10:16 AM

Quote:

Originally Posted by JWJ

My '83 MB 300D has a little blue smoke from the exhaust when accelerating right after a cold start-up. Once the engine warms up the blue smoke disappears. The car has >366,000 miles on the engine. I have a few slight oil leaks coming from the oil pan, etc. that need to be addressed but oil comsumption doesn't appear out of the ordinary.

Would using B100 cause the car to exhibit blue smoke more?

I've read the posts here and this is funny because blue smoke is what happens to vegetable oil when you pour some into a hot frying pan! Try it sometime! Although you will have some wear in your engine at 366,000 miles, I recently had my head totally overhauled and a 3 angle valve job performed and I still get blue smoke when first starting out. Cold starting in the '30's is not a problem and it fires right up the first time. I took mine to Emissions just for curiosity and it passed with flying colors! Blue smoke from a veggie burner, which is what biodiesel is, does not cause concern at federal emissions testing stations. According to them, if it did, they would have to shut down every fast food joint belching blue smoke from their billowing smoke stack grill vents during lunch hour!!!! Veggie smoke is considered biodegradable and not a health threat. Except for what is cooking on the grill that could wind up on your waistline!!!!

Biodiesel300TD · #6 12-03-2006, 10:26 AM

Quote:

Originally Posted by Knightrider966

...Blue smoke from a veggie burner, which is what biodiesel is...

Not really. Veggie oil is used to make biodiesel. They are chemically different.

Biodiesel won't cause blue smoke. Blue smoke it oil being burned. So you have oil getting in the the cylinders and burning. I second the valve stem seals, but I can speak about the turbo seal.

I have the same problem and figured it was the valve stem seals, so I will be watching this one to see if it could my turbo seals.

Knightrider966 · #7 12-03-2006, 10:47 AM

Quote:

Originally Posted by Biodiesel300TD

Not really. Veggie oil is used to make biodiesel. They are chemically different.

Biodiesel won't cause blue smoke. Blue smoke it oil being burned. So you have oil getting in the the cylinders and burning. I second the valve stem seals, but I can speak about the turbo seal.

I have the same problem and figured it was the valve stem seals, so I will be watching this one to see if it could my turbo seals.

Biodiesel is made with veggie oil and trasnsterified with methanol to take the glycerins out. My E300D blows a little blue smoke as well as my E240D and my fairly new Dodge Ram with Cummins Turbo Diesel- low miles, when cold. Biodiesel is still considered veggie oil with additives and I've been buying my Biodiesel from the National Biodiesel Board member distribution network that again just passed ALL the D-ASTM requirements for purity and cleanliness as well as emissions. I'm not saying that the original poster may not have mechanical problems, but none of mine burn oil and compression was really good to excellent in all engines, but they still blow blue smoke until fully warmed up. the Dodge Ram seems to have the shortest warm up time. Some Biodiesel makers will mix about 10% veggie oil to the finished product and they are allowed to do this and this could be causing blue smoke as well. At some time every one will need an engine overhaul to correct these mechanical problems associated with age and wear, but i don't think a little blue smoke is any cause for concern. Clouds of it belching from your tailpipe is another story. If your injectors are worn and putting in a little to much fuel, then you will have a rich running condition that will cause blue smoke too. At 366,000 miles, I would remove the head and take it to a good machine shop for a rebuild and valve job. If nothing has been done to the head up till now, then vorn head components are a really good possibility. Your engine should not blow blue smoke continuously, if it does, you have other problems. But if it is doing it briefly while cold I believe it is not a great cause for concern.

Biodiesel300TD · #8 12-03-2006, 10:55 AM

From everything I've read blue smoke is caused by oil, and black smoke it fuel related.

Knightrider966 · #9 12-03-2006, 11:33 AM

Quote:

Originally Posted by Biodiesel300TD

From everything I've read blue smoke is caused by oil, and black smoke it fuel related.

That is true to a point. If you are burning Dino-Diesel and burning oil, your tailpie smoke will be white/gray. Black smoke will be the result of an overly rich fuel condition when talking about fossil fuels. A gas engine burning oil will produce gray/white smoke. These conditions change when you introduce Biofuels into the picture. Blue smoke will result when using vegetable based fuels that are not being burned completely and combustion byproducts are present in the residue left over from the spent expanding gasses! Throw some corn oil on a really hot grill and watch what happens! It's funny how all this just seems to come back after all these years! when I was a troubleshooting engineer for the Chrysler Corporation, we were experimenting with alternative fuels trying to find fuel additives that would allow us to obtain good performance while lowering emissions and cutting our dependence on foreign oil supplies. Remember MMT lead substitute? If you lived in the then emerging emission control areas requiring boutique fuels, MMT turned your exhaust pink when you punched it! (Not really manly when driving a Corvette!) Whenever vegetable fuels are used, blue smoke is a sign of an overly rich fuel consumption. It just seems to be characteristic of vegetable based fuels. Burning oil in an engine while using pure synthetic oils will often cause blue smoke too since synthetic lubricants are often plant based. An emission test will help you determine where the smoke is coming from. Depending on where you live, emission testing will pickup the combustion by-products of burning engine oil and translate the results into unburnt hydrocarbons-smog! I know this gets awfully complicated when you start talking about alternative fuels, but the old rules for trying to figure out what is going on often don't apply when using pure plant fuels as motor fuel. The best way and the easiest to tell the difference between a smoking exhaust from fossil fuels and plant fuels will be the smell. This is more accurate than the color. Biodiesel will smell like cooking grease, fossil fuel will smell acrid and your eyes will water and burning engine oil will have a heavy chemical smell and take a long time to dissipate.

Here's a fun one! An overly rich Ethanol condition will smell like a beer brewing vat and have no color!! Good Luck and let us know what happens!

aklim · #10 12-03-2006, 06:25 PM

OK. if you think it might be the B100, switch back to regular diesel and see what happens.

Ara T. · #11 12-05-2006, 04:45 PM

I'd suspect the rings or valve seals rather than the fuel. It's not like its an uncommon thing for them to wear out by 300K.

rrgrassi · #12 12-05-2006, 05:30 PM

Every motor oil consuming vehicle I have seen had the blueish smoke coming from the tailpipe. It smells pretty rank as well. I have never seen blue burning veggie oil, unless it's blue corn oil?

winmutt · #13 12-05-2006, 05:51 PM

Dont use B100 in this weather, you are going to have alot more problems than a little smoke.