Expected life expectancy from WMO?

[quinnf]

Thanks, Admin, I thought he'd never go.  Life's too short to read through endless rants and bickering.

q.

[BioHazard]

Something else to think about, do we have any reports of WMO killing any engine before 1000 hours?

[DRDEATH]

You know this is a good idea. We have detrmined that the waste product of using WMO is ash. Well is it in such small amounts that it takes hundreds of hours to build up enough to create a problem? Or in a healthy engine is some of it passed out of the exhaust until something changes within the engine which allow it to build up. Because there are not many engines you could throw a hand full of fine sand in and it would run 2000 hours.

If in a healthy engine what if anything could be done to send the little nasties on out of the exhaust to keep something from hapening anyway??

I noticed the compression had decreased if I remember correctly on Bill and Spences engine before complete failure.

These are some questions that merit some discussion if anyone would like to chime in. Bill or anyone with an extended run time with WMO? DD

[mobile_bob]

the only way i see we are ever going to get to the bottom of this is through careful testing

one test that might be useful is to collect some of this ash, do some analysis on it, maybe under a microscope
and do some abrasive testing with it mixed in clean oil and see how abrasive it is against things of various hardness.

another test might be the 100 hour test, where you take a new engine, carefully document all measurements like bore diameter
piston diameter, ring width, groove width etc, along with taking a look at the various wear surfaces under magnification and photograph
them as well,, run 100 hours tear down and repeat the inspection, run another 100hrs and tear down and repeat inspection, then if all is
still pretty good then stretch it out to 200hours and repeat, go another 200hours and repeat and if all is well stretch out the interval to 500hours and repeat.

at some point we determine the severity of the problem with a specific engine running at a specific load, if it is determined that there is a problem then we can develop a serious of tests designed to make the waste motor oil work as fuel over a longer period.

the test engine will have to be of reasonable quality of course and will have to start out assembled correctly and cleanly, the air intake and air cleaner will also need to be first rate and the oil change intervals will need to be regular so that we don't introduce any other variables of substantial quantity that might skew the results

not an easy task, and maybe we don't get highly accurate results and data, but we should get some relative data that is very useful if interpreted correctly.

bob g

[billswan]

Well guys

Like I said in a post in another thread, I have been very busy all day and then I get a pm from DD and come to the forum and my gosh it sure looks as though the place has been all stirred up.

My 10/1 started showing blow by at 700 hours +or -  and in the last 1000 hours since late November it wore itself down to junk. The cylinder that is, the rod bearing although I did not remove it had a very good "feel" a term that an experienced mechanic would understand. Again I will state that it is my opinion that the quality of the cylinder parts that my 10/1 had would be bottom shelf and the listeroid community over in India should be ashamed of the stuff.

Welcome to the forum davidgr I think your post is very valuable it proves that QUALITY parts can resist some of the perils of WMO use as fuel.

If only a cylinder assembly of induction harden and quality rings + quality piston could be secured for a lister-oid it might make a big difference.

Hope to get my 16/1 thumping this weekend it is a Metro and is much better quality wise than the 10/1 Omega. I fully intend to run it on WMO of varying %"s and will keep the forum informed of it's demise. My guess is it will die a slow death also but I am more than willing to sacrifice another cylinder assembly. To see if a way can be found to burn wmo and keep the engine going a lot longer than 1775 Hours.

Bob I am hoping to get a 1000 hours on this next engine by spring may be I can disassemble it then and measure the wear. I have already had it apart and measured everything on the top end and have some pix. The thread has been started but I have not had time to post but 1 pix. Will try to get all the measurements and the rest of the pix up in the next week. Have been thinking a daily measurement of crankcase vacuum might be a signal of ring and bore condition. Will try to do and document that.

Spencer1885 man oh man not sure what to say to you sir. Please try to find a way to not sir the pot so hard. I VALUE your findings as it was your post over at LEF that peaked my interest when you started to tell of your troubles with your 6/1 and the accelerated wear. I am a man with poor keyboard skills and have a hard time putting my thoughts on paper so to speak. I sit here and want to reach out to you but just do not know what to say..............

Billswan

[mobile_bob]

Bill

if  you want to measure the crankcase blowby, you will likely want to use a surge tank to buffer the crankcase pressure
so that it can be measured

if  you take a tank such as a 5 gallon freon tank or some other similar size steel container, and connect into one end the crankcase
breather, and out the other side connect a length of pipe the same size as they crankcase vent, the puffing of the single cylinder will be
softened to a much lower intensity so you can then measure the blowby exiting that pipe if you just insert a fitting T 'd into the exit pipe.

use a U tube manometer which if you don't have can be easily made with some of the clear plastic tubing, some dye in water and a tape measure or yardstick for a gage.

if you try to measure without the buffer tank, you will get such pulsing that determining a blowby value might be very difficult.

just passing this along, just in case you weren't aware how a buffer tank might be used to get a usable measurement

i agree that one ought to be able to determine from the blowby what is happening with the engine, if you test with a stable load and rpm

actually this sort of setup would be most beneficial to anyone with a new engine wishing to break it in correctly,  with the use of crankcase pressure one can load the engine in steps and run it at each level of loading until the rings seat properly, without fear of overloading.

bob g

[Tom T]

Bob would the  crankcase test used on the GMC through flow Diesels the 271 371 and so on be the test that's needed hear? I blew a disk out in my lower back and well not quiet with it upstairs but I thank you know what I am talking about. Tom T

[mobile_bob]

on the two stroke detroits (53, 71, 92 and 149 series) i don't recall ever measuring crankcase pressure, however
you do measure air box pressure via one of the drop tube's/pipes and a manometer

its been nearly 30 years since i last did any measuring on one, however i still have my slack tube dwyer manometers
and my service manuals that have the spec's and illustrate the test.

with the cylinders being ported, there really isn't the opportunity for crankcase pressure like there is in a 4stroke engine
any cylinder blowby exits the ports rather than making into the crankcase in the detroits, so the airbox pressure increases
with cylinder leakage.

while i remember the test it is not something that is routinely used to determine the condition of a detroit, things like starting
and the amount of oil bypassing the oil control rings into the airbox and out of the drains, onto the floor is a better indicator
of engine condition.  basically if the engine starts and runs good it would be used until such time that it consumed more than about
a gallon of oil per 1000 miles (warrantee limit) or as much as a gallon every 500 miles or so for anyone having to pay for the overhaul himself
(out of warrantee).

yes either of which would have lots of white ash deposits on the piston crowns and the valve heads, stems and in the ports.

bob g

[Tom T]

I remember from my army days 196..... we did some thing  on the crankcase along with the other test it was used to determine the over all condition of the engine.. a lot of years gone by since then. Tom T

[dieselgman]

Crankcase vacuum is the standard "test" in a Lister to determine engine condition. It is measured in inches with a manometer as suggested and is often included as standard equipment in a generator room to indicate when service is required. I am not certain about the specifications on the original CS product line but on newer 1800 rpm machinery it is from 1 to 3 inches...

We have an interest in developing quality parts... an induction hardened bore is of interest - we can investigate. Some input has already indicated that the Lister hard chrome bore lining did not survive WMO. On the alloy pistons, much has already been done. This develoment includes LM13 high silicon alloy in the piston body, a steel top ring-land with keystone fire-ring and chrome moly on SS for that important wear part. Most of this has been done for the higher speed Lister industrial engines, piston wear is a much higher issue with many of these - especially pump-jack applications. Our results have been proven in the field, but only with clean diesel fuels in DI engine types.

dieselgman
Diesel Electric

[BioHazard]

How about one of those surplus center Yanmars as a cheap WMO burner? Would the more modern engine respond worse to the WMO, or would it possibly be better, with better build quality, like the Changfa? At today's diesel prices, you'd only need to burn about 250 gallons of oil to pay it off. The same could be said about the commonly available chinese air cooled diesel, total engine cost is only slightly more than a listeroid rebuild.

Would an air cooled diesel burn WMO better due to higher operating temperatures?

I also wonder if it would be helpful to spin at higher speed when burning WMO, possibly blowing more ash out the exhaust?

I really want to see some experimentation with water/steam injection, but I don't really have the funds for diesel test engines right now.

[davidgr]

A few good points mentioned, and I think BobG got it right. The way to scientifically determine what causes wear can only be done through tests and not what I or anyone else considers to be a fact. I will place my faith behind scientific testing any day.

In effect this means we can have one, or two ways in which wear is caused. Mechanical or chemical, or both.

Testing the deposited ash for acid to me sounds like a basic process and should not cost much. Testing particles of ash to determine if they are above a certain roughness is the final test, we hope.

I got our aircraft guy on the radio this morning and asked if he would compare the Listeroid piston rings and valves against the Changfa items. He gave a reply an hour later and he said..... the Changfa rings are far harder and break with the sudden 'snap' you would expect, whereas the Listeroid rings bent first and then snapped with a slow and 'unexciting' break. They are his words not mine, by the way. The Changfa valves are very hard and the seats also good quality. I sent an email to my supplier also today and asked if he could give some run hours on valve seat wear time. My reason for asking is if the ash is indeed akin to sanding parts I should see it happen in my engine.

I also thanked my aircraft guy for breaking my spare piston rings.

David

[DRDEATH]

David remember in the name of expirementation no cost is to much. LOL Stay well. I would love to hear more about you application with yours and friends engines. DD

[billswan]

Crankcase vacuum is the standard "test" in a Lister to determine engine condition. It is measured in inches with a manometer as suggested and is often included as standard equipment in a generator room to indicate when service is required. I am not certain about the specifications on the original CS product line but on newer 1800 rpm machinery it is from 1 to 3 inches...

We have an interest in developing quality parts... an induction hardened bore is of interest - we can investigate. Some input has already indicated that the Lister hard chrome bore lining did not survive WMO. On the alloy pistons, much has already been done. This develoment includes LM13 high silicon alloy in the piston body, a steel top ring-land with keystone fire-ring and chrome moly on SS for that important wear part. Most of this has been done for the higher speed Lister industrial engines, piston wear is a much higher issue with many of these - especially pump-jack applications. Our results have been proven in the field, but only with clean diesel fuels in DI engine types.

dieselgman
Diesel Electric

Well guys

I have seen the LM-13 4 times now, once on the face of a piston in a pix here or on LEF i believe the engine was crofters could be wrong there. Then I read it in the post of dieselman quoted above and it also appears on the pistons of both my wore out 10/1 and my 16/1. My experience says the ring lands in my 10/1 wore like soft shit on my 10/1 so I guess we have a idea what my 16/1 has in store. 

Read enough you might just learn something.

Well off for another long day be back here in about 15 hours, hope no one else gets suspended while I am gone!

Billswan

[Crofter]

Davidgr; interesting info on comparing the different engines component hardness. I have zero experience burning WMO in an engine but from experience refitting piping in industrial settings have seen that there is very often a chemical component as well as mechanical material removal. Temperature range can be critical and hotter is not automatically worse for wear. Chrome plating is a very broad term and lots of variation on processes for different metals. I have seen failures on shafting in chemical environments due to penetration of the porous chrome and attack on the underlying copper and/or nickel bonding layers that simply let the plating flake away: the culprit was not the chromium but the bonding treatment. If simple abrasion is a cause there usually are patterns of centrifugal effects and concentrations where velocity is highest.

It sometimes takes a lot of systematic detective work to get to the root cause of a problem and often then a number of liveable cures become apparent. The more eyes on the problem the less chance of someone treating as a fact, that "The waving of the tree branches causes the wind to blow".

Simply too many loose ends and no process of elimination. In brainstorming, every suggestion is a good one. The threads on this subject are almost a classic example of how not to solve a problem. I have to admire the patience shown.