I've got an 85 300TD, our workhorse. 269 on the clock, runs well, but does have some blue smoke. And shs's very cranky when cold (don't know if it's injectors or a lazy cylinder). In any event, you guys with the high milegae diesels, are you using any engine additives (not techron or redline fuel additives)for better/longer life? Any thoughts appreciated, thanks in advance. allen.

This may sound like a smart alec remark, but it is not intended to be.

The only additive I use is added oil changes, which include the outstanding additive package that comes in every can of modern engine oil.

Good luck,
Change oil hot and change oil often,

I have to agree with Larry about doing more frequent oil changes if needed. Oil additives are generally just modern day "snack oil". The most famous of course is Slick 50. 2 things that you should know about Slick 50 is 1. they were sued by the Federal Trade Board for not being able to prove that their product did what it was advertised to do. 2) The Teflon that is in their product was created by Dupont, and Dupont clearly stated that teflonin any form should not be used in an internal combustion engine. Teflon apparently likes to clump together and needs special additives to keep it from doing this. So Slick 50 (a Quakerstate product) has to put in these "stablizers" in the mix to prevent this. Should these stablizers fail then you'll plug up the small oil passages in the engine. Also if you think about the claims any of these products make about coating the metal to reduse where. Well let's take that one step further. The engine engineers made the oil passages a set diameter, now if you go and coat the oil passage with Teflon, now the diameter has change. Granted it's a minor amount, but the engineers made that oil passage the original size for a reason. If they wanted the hole to be smaller then they would of built it that way. I look at these "coating" additives like cholesterol for the engine.
My engine also has some blue smoke, but only when it's cold. Once then eninge is all warmed up it goes away. How is your oil consumption? Maybe you can try a thicker oil.

__________________
1999 MB SL500 (110,000 mi)
2004 Volvo V70 2.5T (220,000 mi)
2014 Tesla Model S 85 (136,000 mi)
MBCA member

One very successful repair I did, was to replace the valve stem seals. Next time you adjust the valves, go a little further and give that a try. It is a simple job, and about $10.00. I had a remarkable change after I did mine.

Are you saying the moly products in the part shop are not anything that will help an older engine with high miles????

I have used Slick 50 in all my vechiles, including Cummings & Mercedes Diesels and it has worked for me, but to say I have read all the lawsuits against it and I think they had engine problems before they added Slick-50.

Personnaly, I would not use any oil additives. Just Mobil Delvac 1 oil in the engine and a half bottle of Redline Catalyst in the fuel every few tanks results in virtually no smoke at 300K miles for me.

__________________
Steve

1992 300CE Sportline Sophie
1990 300E Emma - in the family
1979 240D Josephine - sold, but not forgotten
2004 Pacifica AWD

http://web.mac.com/dakota/Mercedes/Home.html

300TD, 300+clock, regular oil changes, Redline, no probs, nuff said

Hey Patsy....no fair flying under the Radar! Register ..so I can e-mail you. I'd like to know more about the valve stem seal job.

Ernie

Allen:

No oil additive is going to replace wear. Valve stem seals will greatly reduce oil comsuption if the valve guides themselves are good, and you can check that when you put the stem seals on.

New stem seals are cheap, but if you can't (or would rather not) adjust the valves, have it done.

to replace:

remove valve cover

Set engine to TDC and remove follower arms (MB says use new stretch bolts).

On #1 (ONLY for the moment) remove the cap on the valve stems and the nut underneath. Lift off the spring cover and the spring. Valve will not fall into the engine because the piston is just under it (and why you one take the nuts, etc off for #1!). The valve stem seal fits over the guide (sticking up from the head with the valve sticking up out of it).

Pry the old seal off and put the little plastic "condom" on the threads on the valve stem (else the threads will destroy the new seal).

To check the condition of the guides lower the valve a little and try to wiggle it. If you can feel it move you need a valve job -- the guide is shot. Acceptable clearance is 2/1000" or less

Oil the new seal and place over the valve. Press the seal into place on the gude with the MB tool. Substitutes may work, so long as the seal is properly forced all the way down on the guide -- there is a spring in the new seal that holds it on.

Replace the spring, spring cover (it is keyed), the nut, and the cap.

Rotate the engine so that the next piston in the firing order is at TDC, then repeat above instructions. Have a care that you are working on the correct cylinder! If not, and you drop a vavle, you may have to remove the head to retrieve it!

When all seals are replaced, re-install the cam followers and adjust the valves -- 0.004" for intakes and 0.016" for exhaust.

Replace valve cover, using a new gasket if the old one isn't perfect. Wipe the head where the gasket seals perfectly clean -- use carb cleaner or solvent. It must be dry or the valve cover will leak!

Peter

__________________
1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!