ASH Content

[Lloyd]

Hi All,

A couple of the discussions on burning WMO seems to be fortuitous to an issue I have been wrangling with.

In my old boat I have a couple of vintage 1962 Perkins 6-354's, I majored them in 2002, I have always run Delo 100 30, the engines now have about 1200 hrs...just getting broken in.

When I changed the oil the last time(I change it twice a year, once in spring and once in fall) I read the labels on the Delo 100 and 400. 100 said it was for 2 cycle, and 400 said it was for 4 cycle. So I am thinking I have been running the wrong oil, the guy at the counter said that the 400 has detergent, and that was the only Difference. So I thought running a little detergent wasn't a bad thing, as I had new engines, and I changed the oil so regular, that I needn't worry about dislodging  all manner of gunk that might fowl the pickup screen and passage ways.

Just before the discussions on the fears of burning WMO, I spoke with a diesel mech. on the dock. He said you have to be careful of burning 400 in older designed diesel's  because the ash content can knock out the rings, and score liners. I have only run the 400 for about 30 hrs, He said get it out as soon as possible, bc he says he's seen damage caused by the ash in less then 100 hrs.

HELP...anyone Cognos/Crofter any others that know oil and old style diesels...any answers???

Thanks,

Lloyd

[cognos]

I'm not an expert on these two oils. Or on diesel engines. I'm a process guy, with a specialty in additives.

But the advice of the mech sounds right to me... and the engine manual should spec the oil for the engines, and that's the oil that should be used... if it's still available.

Detergent oil in an engine not designed to use it can cause problems. Most people think that it's all about just dislodging crud and allowing it to circulate  to parts of the engine that wouldn't see it if the detergent hadn't suspended it in the oil.

What is becoming apparent is that it isn't all just a physical problem - the additives themselves can be problematic, bind with contaminants chemically to form some nasty compounds as well, and some of the additives can be abrasive if burned.

And some of the additives used today are vastly different from what was used in the past - today's oils contain different detergents than they did in the past. What caused no particular problems in the past may be quite a problem today.

[playdiesel]

I have not followed the entire WMO post thing that you reffernce so If I get out of turn here slap me around a bit. Before you get too riled up remember that they are burning it for fuel, you have it in the crankcase and are buring some small part of it as incidental consumption, big differance.

In my long experiance working on engines 90% off all so-called "oil problems" were never any such thing to begin with, pure horse hocky! More like lack of oil or dirty oil problems they did not knowabout or did not want to admit. People run engines with out servicing them till they knock and then change the oil looking for majic to happen, people run them out of oil, then add oil thinking it will fix the knock. Then when it doesnt, they blame the oil. You and I read it all as "the dang blame oil screwed my engine up!!!%^$#%. As I said, pure horse hocky (now that oughta raise some hackles, LOL)
All that being said and back to your questions and concerns. The damage from using detergent oils and non-dertegent oils interchangably is both real and documented. BUT the problems are very much magnified when ALL of several conditions exist. 1. The use of detergent oil after non-detergent. 2. Large amounts of existing sludge build up exist. 3. None to poor filtering. 4 extended serice intervals.

You are correct in your thinking that with your newer rebuilds and your rigorous service routines that you have little to fret about, that's my bottom line.

[cognos]

Ya, I'd agree with all of that. No problems - right up until there are! Then it's a whodunit.

[veggie]

Just wondering ....
Where does that place synthetics?
If I wanted to run Rotella 100% synthetic in my roid, would I consider the syn oil to be a detergent or a non-detergent oil ?

cheers,
veggie

[cognos]

One can buy syn oil with or without detergent.

Might be a bit hard to find non-det syn oil, kinda counter to what it was designed to do - function very well in a modern engine - which mainly require detergent oils.

I can't find any synthetic/diesel compatible/non-detergent oil in the catalogues I have at hand... could very well be a special order I'm remembering...

[Crofter]

Some engines have special operating quirks that might for instance result in a higher than normal piston crown temperature and a non detergent oil may prove better at keeping the rings free. Turbo charged or not, is often key to needing a different additives package. Two stroke vs Four usually result in more oil getting burned. Some engine installations result in unusually cold oil sumps and sludging is a major issue that will likely want to see an additives package geared to that. Some of the VW diesels have an extremely high pressure loading of the camshaft lobes by the unit injectors and their oil spec. is a bit hard to find but experience shows that it is very important to that engine.

In short, I would say there are some instances where the recommended oil is crucial, but there are many more middle of the road ones that, as mentioned, as long as you keep lots of oil in them and change regularly you could run anything that is "oily" but why second guess the manufacturers recommended spec. They have every reason to want the best results for their product.

[TimSR2]

Old diesels love Delo 400, even Detroit Diesel 2 strokes  love  Delo 400. No worries.