Diesels- mechanical vs electronic

[SKYCHENEY]

There was some talk about the Cummins N14 in another thread and I didn't want to post this there, so I started something new.

I love the fact that the old DD's are mechanical and we don't have to worry about sensors or computers going bad at some inopertune time. And, as others have noted, if you should ever have a lightning strike, those old DD's should keep running.

I thought of all of this as I had another Cummins N14 failure today. I really like Cummins and we have had good luck with them, but one of our trucks was shut off while we changed a tire. After that, it would not start. It would turn over, but would not fire. We checked the usual stuff. The fuel filter was clean and the fuel was not gelled and no flashing code lights on the dash.

Well, we ended up having the Cummins tech look at it and guess what? The computer was dead. I asked how and why this would happen and the response was "well, sometimes they just die". Nice, huh? I don't think I'd want that happening while I was offshore somewhere. Oh, BTW, a new computer is $2900. This is not just a Cummins problem. All of the new electronic engines have these types of issues. Progress?

 

[MikeP]

Since it appears that BOTH computers on a Boeing 777 (crash-land at Heathrow) may have malfunctioned and given that the computer systems on the plane are TOTALLY redundant and several orders of magnitude more reliable, tested, and maintained than any pleasure boat engine will EVER be...

It tells me all I need to know...

 

[Mike36c]

Since it appears that BOTH computers on a Boeing 777 (crash-land at Heathrow) may have malfunctioned and given that the computer systems on the plane are TOTALLY redundant and several orders of magnitude more reliable, tested, and maintained than any pleasure boat engine will EVER be...

It tells me all I need to know...

Question is: Why didn't they ground the entire 777 fleet while they figure out what happened? BTW, I love my mechanical cummins 6B's.

 

[Maynard Rupp]

Since it appears that BOTH computers on a Boeing 777 (crash-land at Heathrow) may have malfunctioned and given that the computer systems on the plane are TOTALLY redundant and several orders of magnitude more reliable, tested, and maintained than any pleasure boat engine will EVER be...

It tells me all I need to know...

I wouldn't be so quick to blame the 777s computers. As a professional pilot, I looked into that and pretty well have decided that the crew had their heads up their, well you know where.

 

[Brian Degulis]

We have been installing EC engines both John Deere and Cummins since they came out about 4-5 years ago. So somewhere around 200 engines and I have yet to see or hear of a computer related problem.

Brian

 

[Maynard Rupp]

We are always looking at changing our gas engines. I hope we are smart enough to do it before tank problems. The Cummins QSB electronic engines are about $10,000 each more than the 6BTA 380hp. mechanicals. I am inclined to spend the extra bucks for all the advantages. Syncronisers, single lever controls, no cables, (remember we have two helms, so ours are a little tight), instrumentation that works, quite a bit less fuel consumption, more horsepower,and most important a pretty good increase in the boat's value. I do worry about the computer problems especially in a salt water, hot, humid Miami environment. Who knows, just my .02.

 

[Maynard Rupp]

I forgot to mention that a charter 45' Hatteras here in Miami changed his DDs to Cummins QSM 11s. Hard to believe, but he puts as much as 2000 hours per year on that boat. WOW. The QSM11s now have over 4000 hours and are great. He said the captains say the boat is much livelier and his annual fuel usage is a full 20% less. Interesting eh? He said the whole job cost him $150k.

 

[drburke]

What I am seeing on the web is many are questioning the fuel from China. In fact, immediately after the event, BA had their entire fleet check the tanks for contamination. It seems one engine throttled back 3 seconds after demand, and the other 11 seconds, probably indicating the computers were up. Both engines were actually running when it touched down. Reportedly the electrical systems have been ruled out.

Question: how many of us have had water in fuel, vs engine computer crashes?

We live in strange times, where a worker in a country that makes $6K per year might be tempted to "stretch" a $200K load of fuel, knowing some water can be tolerated by turbines (assuming it doesn't form ice) and that pilots rarely run down to the bottom of tanks.

Different event, but disturbing (Maynard, don't freak out):
http://iagblog.blogspot.com/2007/01/chinese-aircraft-maintenance.html

DAN

 

[MikeP]

OK, I have to admit that despite my earlier post, I have this deep-down feeling that the 777 issue was NOT a software problem but more likely a skin-ware problem...

 

[BUSTER]

It's interesting this thread started just now.A couple of weeks ago I replaced the ECM on one of my N-14's.Only the second one since we have been running electronically controlled diesels,which is since 1993. At 2900.00 you got a good deal if it was an OEM unit,I paid 3200.00 for the one I installed.

A dead electronic engine can ruin your day,but all in all for performance,high torque,high hp and engine longevity of electronic diesels are all far greater than any high hp. mechanical engine.Any type of operating parameter can be programmed into an electronic engine,from automatic shutdown,RPM limits,idle time or a higher hp rating.

I love the pure mechanical diesel theory and have mechanical engines in my boat,but mechanical diesels will soon be a thing of the past,just look at California for an example.That ultra-low emissions mandate is traveling our way.

 

[MikeP]

I have absolutely NO problem with electronic road engines, diesel or gas. They get a lot more testing and operational use/feedback then the almost insignificant number of boat engines that operate in the salt water environment.

In addition, I guess what bothers me is a bit like the airplane thing - if a boat's engines quit you could be in a serious (as in life threatening) situation. If your car (or other road vehicle's) engine quits, you pull over to the side of the road and call somebody.

I agree that it will soon be impossible to buy a "mechanically-controlled" engine in any new vehicle regardless of where it operates.

 

[SKYCHENEY]

It's interesting this thread started just now.A couple of weeks ago I replaced the ECM on one of my N-14's.Only the second one since we have been running electronically controlled diesels,which is since 1993. At 2900.00 you got a good deal if it was an OEM unit,I paid 3200.00 for the one I installed.

$2900 for OEM or $1900 for rebuilt unit with NO warranty. I think the decision there was pretty easy.


I guess the electronic units aren't so bad OTR, but I just keep comparing them with the old NTC 400 Big Cams. Those things would run and run and they hardly ever went down.

 

[yachtsmanbill]

Just wait until Chairman Mao drops the big one and the EMP knocks everything out except for old boats with Detroits.
Now that anyone is reading this thred probably has a clue, and I dont, where in the H E double hockey sticks can I buy Kent-Moore tools??? I am looking for rack gauges and some other sundries for the 71s especially.
OOOWWWEEEEOOOOO some GD magician waves a wand and drops a box full of the stuff in Bubbas lap and he picks his old green teefes with the stuff. This kinda funny bizness really PISSES ME OFF ... GRRRR
Can you sense the hostility ;-) ws

 

[yachtsmanbill]

$2900 for OEM or $1900 for rebuilt unit with NO warranty. I think the decision there was pretty easy.


I guess the electronic units aren't so bad OTR, but I just keep comparing them with the old NTC 400 Big Cams. Those things would run and run and they hardly ever went down.

Last year my pal Franz was running a 20,000 hp tug from the east coast to Sturgeon Bay (Bat Ship) for dry docking and the MANs shut down for a pressure switch that took 2 weeks to get from the hinterland! Is this what its' come to ?
Technologically advanced? 5% fuel savings? Damn the tree huggers! ws

 

[MikeP]

"Question is: Why didn't they ground the entire 777 fleet while they figure out what happened?"

I suspect that they DIDN"T ground them because they have already figured out that it wasn't an "airplane" problem which leaves a crew or a maintainance-related issue. Either that or Boeing has so much clout/influence that they have prevailed upon the powers that be to NOT ground them. That's too scary to even contemplate...

 

[double trouble]

Hi Guys I run the sixth largest truck fleet in Wa. state and we replace ECM's (computers) and ICM's (injecter drivers) on a regular basis along with cam sensors. The biggest cost for us on the E-control engines are the injectors they are about $300 each plus a $200 dollar core charge. The electronic injectors do not like water in the fuel. The high pressure oil pumps that drive the injectors are about $500 for the rebuilt units on the International trucks. The cost of all this is offset mostly by the fuel savings. The old DD may not be the most fuel friendly but they will run for a long time with little or no maintance as we all know of some owners who have never done anything but service the old 12V71 for many years. The new injectors are good for about 125000 miles before you start seeing a loss of fuel mileage. They will run a lot longer before the engine starts to show codes but you will lose up to 2 miles per gallon if the engine HOP(high pressure oil pump) gets weak or the injectors need repairs. The e-engines are getting more reliable everyday but the cost to repower compared to the cost of rebuild doesn't work out for me. I do all my engine work myself so the cost of rebuilds is parts only.The $150 boat bucks in the previous thread would buy a lot of parts and fuel and unless something happens to it I will keep this boat for the rest of my boating career. But each boat and individual have different circumstances. One shoe size will not fit all of us. So the augument goes on. MEC vs E-Controls. Happy Boating ! Steve

 

[Brian Degulis]

It's interesting this thread started just now.A couple of weeks ago I replaced the ECM on one of my N-14's.Only the second one since we have been running electronically controlled diesels,which is since 1993. At 2900.00 you got a good deal if it was an OEM unit,I paid 3200.00 for the one I installed.

A dead electronic engine can ruin your day,but all in all for performance,high torque,high hp and engine longevity of electronic diesels are all far greater than any high hp. mechanical engine.Any type of operating parameter can be programmed into an electronic engine,from automatic shutdown,RPM limits,idle time or a higher hp rating.

I love the pure mechanical diesel theory and have mechanical engines in my boat,but mechanical diesels will soon be a thing of the past,just look at California for an example.That ultra-low emissions mandate is traveling our way.

That's exactly right in an overall view the advantages far out weigh the dis advantages. Remember we had the same concerns about EC in cars. I'm not certain but I think mechanical engines are gone in all but the very small engines. Cummins offers re mans in mechanical but can't sell anything new in this country that doesn't meet the emission standards. I think you would find very few if any new mechanical engines available.

Brian

Brian

 

[Mike36c]

"Question is: Why didn't they ground the entire 777 fleet while they figure out what happened?"

I suspect that they DIDN"T ground them because they have already figured out that it wasn't an "airplane" problem which leaves a crew or a maintainance-related issue. Either that or Boeing has so much clout/influence that they have prevailed upon the powers that be to NOT ground them. That's too scary to even contemplate...

Agreed, simultaneous engine issues are almost always fuel related (except for volcanic ash encounter, extreme turbulence, etc.) Initial reports indicate they had fuel at impact, contamination would be a good guess. Wonder if they are still filling up in China? It's unbelievable no one was killed.

 

[spartonboat1]

Agreed, simultaneous engine issues are almost always fuel related (except for volcanic ash encounter, extreme turbulence, etc.) Initial reports indicate they had fuel at impact, contamination would be a good guess. Wonder if they are still filling up in China? It's unbelievable no one was killed.

Well, Generous Motors can download your computer at will, if you have OnStar. If your GM vehicle halts, you call OnStar and they do an on-line analysis of all vehicle systems on the spot where it sits. So, let's guess that a computer log dump from those 777's was either already in the hands of the Boeing EE engineers, before the plane came to a rest or within the hour. I suspect they had an analysis of all parameters of every sensor to sr. management w/in 24 hours.

If we wait 3-4 years the true story will come out buried in Dr. Dobb's Journal, or some other techie rag. However, if it was "static between the headsets", aka issue between the seat and the controls (USAF Jockeys used to call it that at one time), then that means the software needs to be enhanced to be totally idiot proof.

As far as the ECM failures, the technology is now out there to greatly reduce the cost, i.e. "flash drives". If your ECM fails, you could yourself pop out the old and insert a new for about $25 (why don't I think that will happen?). The really big iron is looking at super -fast flash drives for huge cache memory- trillions of bytes. Almost replaces hard drives at lower cost, while faster.

But, I do like the fact that after my relay logic "push the button" to roll the 6-71 starters, drops out, I am all mechanical.

 

[krush]

I worked at GE Aircraft engines on the CFM-56 (it's on 737's, A318/99/20/21, A340) and learned all about the engine and the computer controls. The computer was double everything and I think rotated "who was in charge" on each start. It cross checked itself and if one was screwy, it would use the other computer.

Sounds fancy, but remember...this thing ran at like 8mhz or something. It recorded some parameters, but it was REALLY simple. Basically it takes readings from all the sensors, looks at a chart, and spits in the amount of fuel.

The GE-90 (which some 777's use, I think this one was a rolls though...British planes and all) was newer and had a more complex computer, but it still wasn't anything amazing.

They do record parementers into memory though. I think they save the last couple flights worth of data. It's been a few years though...i'd have to go check my books.