20/2 lubrication and veg oil

[Ronmar]

I sure don't think hourly is necessary.  I usually run from 4-8 hours at a time.  I probably squirt a little oil on the plunger once every few starts (days).

I would agree. Even with my very poor oiling regiment, I have not run across anything indicating excessive wear due to insufficient lubrication (excluding of course letting the engine oil run down too much).
I have not examined the moving components over top of the heads yet.

My plant is for backup.  If I was using it regularly as heater or charger, it would have some automation in place.  My time spent at sea operating equipment provided by the lowest bidder has caused me to develop habits that are hard to break:)  Particularly with zero automation in place, the most important 3 things I bring to the engine room every hour or so are my ears and nose. I have found as many problems with these as I have with my eyes.  Remember this genset was built by the lowest bidder:). A few drops of oil at these looksee sessions surely dosn't hurt.

[billswan]

Ian

I know what you mean about hijacking and it did cross my mind when I asked but your answer was superb and very informative.

I thank you and it looks like jens did to!!!

Billswan

[oiler]

600 hr oil change .... wow, that is impressive (it could also be a recipe for disaster, it would be for my engine). Something strikes me as not right here. I wonder if there is some unknown issue with my 20/2. Since it is the only listeroid I ever owned, I have nothing to compare it to. I have at least twice as much oil in the crankcase as you have yet it lasts only a fraction of the time. I would be ecstatic with that kind of maintenance requirement !

Yes, odds are that you have goo in your injector pump. If your engine runs in a sound enclosure and the temperature at run time is toasty then it is guaranteed to be goo in the pump. Note that the goo is nowhere near the rack itself but instead in the very bottom of the ip.
I would suggest penetrating oil on the rack first and after that test how easily the rack moves. There should be no resistance at all with all linkages disconnected.


[/quote]

I'll better take my IP apart and have a look inside. The engine is not in an enclosure, but the oil is heated before the IP and the pump is around 70c on the outside.

Do you have an oilfilter on your engine?
As Ian I too fill the sump up to the filler hole to ensure lubrication.

[JohnF]

Jens;

That makes a bunch of sense - and I like "gooify!  I did forget to mention that I start and stop on either diesel or Biodiesel, so veggie does not sit in my Low pressure lines, IP, high pressure lines nor the injector without moving.  That is likely the reason why I have not been seeing many problems with my IP's.

It's all beginning to make sense to me now.

P.S. - don't get rid of your engine, you've done so much work on it that would be a shame.

[bschwartz]

I also start and stop on diesel....... hmmm pattern? 

[JohnF]

Jens;

Usually less than 5 minutes, never much more.  30 mins would be excessive and mean me getting off my lazy ass and going out the the genshed twice - not a likely occurrence!

You don't think 5 mins of diesel would be enough to wash out the veggie?  Seems to me there would be so little left it shouldn't be a problem.

[oiler]

Jens. It makes a lot of sense. I forgot about your enclosure keeping tep's high for a long time.
I start and stop on diesel too, at least mostly i do. Right now it is a 50/50 mix of kero/Medicway.

On startup 15 minutes and shutdown 20-30 minutes, just to be on the safe side.

[vdubnut62]

Medicway?
Ron

[Ian]

Reading through the posts as I have written them, it would occur to me that the number of bearing failures could possibly be attributed to an overextended oil change period. I am sure this has occurred to others too but you have been too polite to say so; Brett has diplomatically suggested that a pattern may be emerging........

The first TRB failure (original Indian bearings) happened after around 2000 hours of running. My neighbour (a farmer who has a superb ear for all things mechanical) had shown a visitor around the engine shed when it was running late one Sunday afternoon and commented on how sweet and smooth it sounded. When I went out to the engine shed later in the evening to shut the engine down, there was a rumble / vibration clearly audible and not right. Only about 3 or 4 hours had passed between my neighbour seeing a sweet running engine and me finding a rough unhappy engine. The engine had new oil about 150 hours previously.  Both bearings showed massive localised wear, not just in the fixed portion but the rotating part as well. Both bearings had peeled parts of the bearing surface and distributed it all over the engine. These bearing shards had got into the big end and scored and tapered the journal. The TRBs were replaced with new SKF bearings when reassembled. The crank was reground and new oversized shells used.

The new TRBs lasted for about 5 weeks. An oil change was undertaken at about 200 hours and then a further 200 or so hours before ONE of the new TRBs started to rumble. When I heard the noise, I was convinced that the noise was coming from the generator but disconnection of the generator proved it was, in fact, the engine. The bearing had again distributed shards throughout the engine and again had got into the big end although this time a bit of very fine emery was enough on the journal plus a new set of shells. This time, the TRB wear pattern was also a little weird; the fixed part showed the peeling previously seen but it was out of line with the loading. I put this down to a bad bearing.

The camshaft was replaced because the exhaust cam showed signs of gross pitting. I could not get the retaining collar pin out by drifting it so had to drill it out. It is not easy to drill out the pin in situ and I ended up misaligned with the drill and pin on the far side. I could have taper reamed the hole out and installed a new, larger taper pin but decided to replace the old 12/1 camshaft with a new 6/1 camshaft with heavier weights (as I run the engine at about 580 RPM) to get a better governor response.

The reason for going through this detail now is to show that the failures tended to occur after rather short oil change periods. I have had so many failures that required strip down (and therefore an automatic oil change) that for most of its life, the engine has had quite short oil change periods. It is only now that I am hoping to run 500 hour oil changes.

However, the failures may also be because I may be rather ham-fisted and a poor mechanic; maybe my actions directly caused these failures. I do not know. I just wanted to ensure that my incomplete earlier posts did not automatically lead others to believe that the mechanical failures must be as a result of extended oil change intervals.....

I hope this helps.

Regards,
Ian

[Crofter]

That quick a failure of TRBs might have some other problems. Failure can be initiated from impact loading in the process of installation or installing accessories (like gib keys). Once a ball or roller bearing failure starts it can go to pieces very quickly. Over preloading on initial assemblly can really shorten lfe as well as can grossly loose setup. Ideally bearing outer races should slowly process around in their location to distribute wear. Lack of radius clearance at either the internal shoulder on the shaft or in the outer race housing can distort the bearings into early failure too. It sometimes takes a bit of detective work to find a cause of premature failure of known quality bearings.

Once a hardened bearing has had a near death experience in an assembly the only way to ensure there is no premature refailure of other bearings is to completely dismantle and renew every other bearing and clean every crevice (such as inside seals) where the minute shrapnel can be hiding. It is as elusive as the casting sand.

I have a feeling that many of these engines start out from factory assembly with some weird and limited con rod insert contact patterns. This would allow early development of excess oil clearance. One of the results of that is quck oil drain out on shut down that results in metal to metal start ups. Once clearance gets beyond a certain point wear is exponential. It has to get pretty bad before you could ever hear it over the background noise of a listeroid.

[vdubnut62]

Ron
Medicway from Statoil. A thin white lubricant for medical use.
Got 200 litres from work.


Oh dear, sorry I asked! 
Ron

[SHIPCHIEF]

 George B called me one day and told me I should come get a new cam idler gear, as the stock iron ones were failing. I had 7 hours on the engine at the time. That's when I found all the sand. I had thought the red paint inside the engine meant there was no sand.....but there I was. I tore down the whole engine and that's part of an other story.
The #2 IP roller on my 25/2 seemed to run very dry. The Injector Pump support casting forms the IP cam case. It's an enclosed cavity with a drain hole near the bottom that re-enters the crankcase. I guess oil is supposed to migrate down the cam bearing in the crankcase wall and provide enough oil for the IP cam/roller and tappet body.  I"m pretty sure all the twins are the same in this.
It had been running pretty dry, so I added an oil line from the top of the oil pump where the pressure gauge goes, to a fitting that I made, drilled & tapped to the cam case to squirt oil directly at the contact point of the cam lobe & tappet roller. It's a drilled out 1/8th inch pipe plug with a piece of small diameter brake tube brazed in thru it. Once it was installed, I bent the tube end to aim the squirt (or drip) onto the cam lobe.
It seems to work. But I don't use this engine like you do. It's my suburban back up generator, and general hobby engine that prevented me from buying another boat, which my wife thought was grand, especially when the power went out for a week in the winter of 2007. 

[SHIPCHIEF]

Jens;
My 25/2 ASHWAMEGH came with a 4 sheave pulley, which I plan to use someday for various loads, like an automotive air conditioning compressor, an air compressor, or a 12 volt alternator etc.
I was thinking it could also run a automotive power steering pump, for engine lubrication. then it would have a continuous pressure and flow that I could use to keep the entire inside of the engine oily and pass the oil thru the oil filter and heater faster. Also, I could use a low oil pressure shutdown. I really think the cam needs more lubrication than the 2 stripes of oil thrown up by the dippers. That oil lands on the tappets and cam lobes, also the oil pump plunger and eccentric, but not so much on the cam support bearings. I'm not sure how well the cam gears and governor are oiled either?
I built the alarm and shutdown panel years ago, but the oil pump pulsations don't work with my panel...But the Henry Dancuse turbo charged 6/1 has a belt driven oil pump, probably to provide adequate oil to the turbo. I liked the idea. 

[veggie]

Jens,

Use that spare 5'' pulley on your crank to drive an oil pump like the one in this video.
Put an orifice in the discharge line to create some back pressure.
Put a sensor in the discharge line ahead of the orifice.
If the pressure drops, kill the engine.

http://www.youtube.com/watch?v=NDrEpgHuFBM&feature=related

veggie

[LowGear]

Hi Veggie,

I hope all of you can see the desperate attempts to overcompensate this poor fellow is going through.  I'll bet his parents made him keep his room clean, orderly and even expected the trash taken out daily.  Are these shop Gods born or made?

Am I the only one that looks upon this extraordinary program and wonders "How the Hell?"  I wish my workshop were that clean just once every couple of years.  That's probably the secret.  It's clean every day.  I'll bet he even gets rid of stuff that that hasn't been used in 5 or 6 years.

Ok, OK!   Here's the question.  Has anyone set up a system of fuel tanks that would automatically run the starting and ending fuels?  I'm visualizing three tanks.  A two quart starting tank and a two quart ending tank that takes over when the large running tank nearly empties or the shutdown valve is closed/opened?  The last part is how do we shut down the engine before running completely out of fuel which can result in a purge to get things started?

Casey