Lifetime engine data recording - Caterpillar (C32 ACERT)

[Nautical]

very interesting post J, especially when looking at the displacement / semi D market, still surprises me (sort of) when people look at a LRMY and suck teeth when they see 2000 hours, almost believe the thing is for the knackers yard. In reality 90% of owners of that style of yacht (being mostly more mature types) will be long dead and gone before they need a rebuild, probably their offspring too! . Much more important is servicing and how well the engines have been looked after, hours are a lower priority than actual maintenance. Alternatively, more worrying sometimes is a very low hour LRMY, 10 years old, sketchy service record, often turns out a bag of nails. Gimme a few thousand hour very well maintained CAT/Lugger/Cummins motor any day over a low hour ropey record motor.

 

[Deleted User YDKXO]

You'd want to be cautious using such a range figure. If tanks are perfect cuboids it has some chance of being right enough. It is likely measuring varying resistance of a tank sender and deducing remaining fuel from some parameters initially entered when the boat was first set up. They probably set it up so it understates the range of course, to be safe

No there is an electronic sensor in the fuel pipe which leads from the base of the tank to the sight guage

There is only one fuel tank on my boat. How the sensor works, I'm not sure but I'm guessing it's a pressure sensor because there's a note in the operating manual for the boat warning that changes in temperature and fuel quality may alter the specific gravity of the fuel and hence the sensor reading. There is also a warning about the trim of the boat affecting the sensor reading as well.

The remaining fuel volume is displayed on the central MMDS display (these units are made by Boehning I believe). Yes I have changed the language to English now!

Separately mike, does MMDS know the boat's SOG via nmea, so it can tell you instantaneous litres per mile?

I wish, no it doesn't, which is a big shame considering it must use SOG to compute the range. I have used the lph data from the MMDS displays and SOG data from the plotter to compute my own graph of nmpg against speed but of course its only approximate

 

[jfm]

Thanks Mike. Interesting stuff. Yes, it must be a pressure transducer. Perfectly ok, except it won't read well at low pressures ie the last 10%, which as per the sight gauge discussion above is when you care most about an accurate reading. It looks like we all have good fuel management generally but none of us has accurate fuel volume data for the last 10%. Oh well, first world problems and all that

You could just create a mini n2k network with 5 Ts, being gps mushroom, a single small 110mm square garmin display (not a plotter), 12v power and two maretron j2k100. The maretrons being linked (3wires) to the mmds units. then you'd have instantaneous LPH readout

What country in your patch does red stained diesel?

 

[Lozzer]

Nautical totally agree with you. I skipper a Princess 85 and we run 90% at displacement speed so in three seasons we have 1250 hours. When buyers look at this on the sales spec they suck their teeth. Ooh way to high for age of boat.

Interestingly the first people to come and see our boat put an offer in and two days ago we did our sea trials. When we showed a them the fuel rats at all speeds they then appreciated our mode of operation. Yes if you want to do 27 knots you can but we find at 11 knots with the stabs running the crystal doesn't fall over as much....

Hoping to finalis deal in the next few days..

JFM. I was once delivering a V45 and my fuel dropped from 10% to 0 in the space of 5 mins. Eek, nearest fuel stop 15 miles away. My planned stop had decommissioned their fuel berth....

As you say we all seem to be on top of the fuel. Good thread

 

[Deleted User YDKXO]

You could just create a mini n2k network with 5 Ts, being gps mushroom, a single small 110mm square garmin display (not a plotter), 12v power and two maretron j2k100. The maretrons being linked (3wires) to the mmds units. then you'd have instantaneous LPH readout

You mean nmpg or nmpl rather than lph? Yes I suppose I could but my own figures indicate that the nmpg curve on my boat is pretty flat throughout the planing speed range so knowing instantaneous nmpg at any speed isn't going to help me to save fuel very much. The only thing I do know is that I save a lot of fuel doing 9kts instead of 25kts

What country in your patch does red stained diesel?

It isn't red, its just the photo which makes it look red. I replaced the stained non slip floor covering over the winter. I guess yard mechanics aren't too careful about spilling diesel when they change filters

 

[Hurricane]

Bit busy at the moment preparing for annual lift tomorrow but I thought I'd better join in the "knock MTU" thread.

I think we are all talking about published maintenance rebuilds and that MTU has a shorter time than others.
I've just checked the maintenance schedule for our MTU CR2000s and there is very little required until 4000 hours.
Yes, the 4000 hours service is a big one and requires a QL3 (and some QL4) qualifications - I'm only qualified to QL1 but (on paper) I can do all the maintenance until the 4000 hour service.

We all respect Latestarter and his expertise/experience but I think even he is referring to these engines in a commercial environment.
How many engines supplied to the leisure market reach in excess of 4000 hours anyway and I think that manufacturers build them to a lower spec for our environment anyway.

So, we need to be realistic and take other things into consideration.
As an end user dealing directly with MTU, I have had exceptionally good service. An example was my intermittent problem last year. I was able to have an extensive email conversation with a support engineer. We exchanged photographs and as a result, we narrowed the problem to a poor electrical connection. Once the connection was remade, the problem went away - I'm confident that the problem won't reoccur but I'm happy to plan some long passages over the next few weeks. It is a great confidence builder when you do these kinds of things and MTUs support has been far better that anything that (say) Volvo can offer.

A lot of this confidence has been a direct result of MTU "throwing open" their manufacturing and training department to "owner operators" like me. Not only does it give you the insight into the engines themselves but it creates an even better communication path to the people who know and can help when it matters.

I believe that our engine room was designed for MAN engines and adapted later. We all know that the MTU unit is smaller (although slightly taller). This means more space and in our case, we can reach most, if not all the critical components. At a recent exhibition, we fell in love with a Ferretti engine room - with MTUs - there was a massive amount of space all round.

So, if presented with the options again, I would definitely consider MTU for power.


Nuff of that - onto some stats.

Not sure what this all means but I ran the "girls" up a few minutes ago and read the data from the displays.

Fuel Used
Starboard - 43850 litres
Port - 43261 litres
So thats a total of 87111 litres

Engine hours
Starboard - 698
Port - 698

I've also checked my ships log which has recorded all the fuel loaded since the factory in Plymouth.
Total fuel bought at the pump is 91,195 litres.

We don't use the generator that much - that is currently showing 368 hours which probably doesn't account for the discrepancy but I'm not worried.

It all seams to me to be in the right ballpark. Maybe you clever guys can read something out of our stats??

 

[jfm]

You mean nmpg or nmpl rather than lph?

Yes, my mistake.
I take your point but actually you do get useful data from the instantaneous read out. It tells me that plenty of trim tab adds no significant fuel burn, and that full versus empty tankage (about 53 vs 60tonnes) adds 1 - 1.2 litres per mile of burn. I therefore keep tanks light mid season unless I'm going somewhere. MYAG dumps his water on a long run and makes it at the other end!

 

[Deleted User YDKXO]

Fuel Used
Starboard - 43850 litres
Port - 43261 litres
So thats a total of 87111 litres

Engine hours
Starboard - 698
Port - 698

Thats only 62lph per engine on average. You're not going fast enough! I guess that reflects the amount of 'pootling' you do?

 

[jfm]

... read something out of our stats??

Two Q's (!)

Was the boat supplied to you in Plymouth full or empty?
How full are the tanks right now?

The reason I ask is that the 91k figure "ought" to be lower than the 87k figure, you'd expect. If you had a full tank on delivery and a full tank now, @4000litres, the fuel bought should be adjusted to 83k and then the engine electronics would be over reading by 5% which is consistent with Lozzer's observations and the stuff theorised above

 

[Deleted User YDKXO]

Yes, my mistake.
I take your point but actually you do get useful data from the instantaneous read out. It tells me that plenty of trim tab adds no significant fuel burn, and that full versus empty tankage (about 53 vs 60tonnes) adds 1 - 1.2 litres per mile of burn. I therefore keep tanks light mid season unless I'm going somewhere. MYAG dumps his water on a long run and makes it at the other end!

Yeah you're right. I know intuitively that full water tanks make a difference to speed/consumption but I don't know by how much although for a long trip I make sure they're near empty. Similarly I travel with light fuel tank if I can for the same reason but I don't know what difference it actually makes. It would indeed be interesting to know the effect on fuel consumption. Tabs is an easy one though. On Ferrettis in general tabbing down increases speed unless you're close to flat out so I always go everywhere with the tabs well down at normal speeds

 

[jrudge]

Why would they over read? If i was a manufacturer I know which way i would want then to read - oh look how little fuel you use!

Jeremy

 

[Hurricane]

Two Q's (!)

Was the boat supplied to you in Plymouth full or empty?
How full are the tanks right now?

The reason I ask is that the 91k figure "ought" to be lower than the 87k figure, you'd expect. If you had a full tank on delivery and a full tank now, @4000litres, the fuel bought should be adjusted to 83k and then the engine electronics would be over reading by 5% which is consistent with Lozzer's observations and the stuff theorised above

Yep - I didn't take that into consideration
We didn't take actual delivery in Plymouth but we went with the boat on her first passage to Swanwick.
Looking back in the log, she took 2200 litres in Swanwick - about right if she had been full in Plymouth.
So your calcs seem consistent with Lozzers.
I think I'll modify my log to reflect this.

EDIT
Yes - full tanks at the moment.
Been full all winter whilst watching the fuel prices dropping!!!
1.18 euros here in Spain at the moment.

 

[Latestarter1]

Why would they over read? If i was a manufacturer I know which way i would want then to read - oh look how little fuel you use!

Jeremy

#1 Credibility
#2 Safety

Detroit Diesel played that silly game in the early days of the Series 60 motor and it took a good few years to restore confidence in the accuracy of data provided by electronic engines, that as well as using electronics to cheat on emissions. Culture which led to hugely punitive fines by EPA and Roger Penske having to sell out Detroit to Daimler Benz.

 

[jfm]

Yep - I didn't take that into consideration
We didn't take actual delivery in Plymouth but we went with the boat on her first passage to Swanwick.
Looking back in the log, she took 2200 litres in Swanwick - about right if she had been full in Plymouth.
So your calcs seem consistent with Lozzers.
I think I'll modify my log to reflect this.

EDIT
Yes - full tanks at the moment.
Been full all winter whilst watching the fuel prices dropping!!!
1.18 euros here in Spain at the moment.

Actually I think my logic was mixed up. YOU have bought 91195 litres, if I understand correctly. Take away the 4000 still in your full tanks right now, but add the 4000 litres that Princess put in the tanks at Plymouth (on the basis that fill up isn't in the 91195 litres, but the 2200 in Swanwick is in the 91195), gets you back to 91195 fuel consumed

368 genset hours at 4 litres/hour brings it down to say 90,000 fuel bought for the engines, so it is surprising that the engine ECUs say 87111

Confusing topic Mike and obviously a first world problem! I'm wondering if perhaps you have could have missed out one fill up in your listing that adds up to 91195. Or are those pumps at St Carles overcharging you 10% ??

If you are full now, and have a note of the 87111 number, you can do a rain check next time you buy ~3000 litres to fill up. Compare the pump litres with the ECU increase above 87111.

If any consolation, I too filled up in September for the winter, at high oil price and 1.20 FX rate. Probably cost myself 3 grand there...

 

[Deleted User YDKXO]

If you are full now, and have a note of the 87111 number, you can do a rain check next time you buy ~3000 litres to fill up. Compare the pump litres with the ECU increase above 87111.

I do that every time and every time the pump volume delivered and the tank reading correlate to within a very few litres so I would be surprised if Mike's difference is down to being shafted by fuel suppliers There must be another reason, as you say, possibly a recording error

 

[Latestarter1]

I have CAT c18s and hence get similar info. At idle it normally says fuel flow is 0.00 LPH which is probably a bit optimistic!

My average load is some 30% - so glad to see JFMs is similar!

Suggest that it may be worth switching data screen back to U.S customary units and see if it give a reading in gallons/hr.

% engine load is very useful on sea trials with new vessel, however gives me the ab dabs when I see WOT numbers in the high 90% at WOT when vessel is clean, what people seem to forget is the fact that system cannot display engine overload. Once you get 100% load display will continue to show 100% even if engine is running at say 150% load.

 

[jfm]

I do that every time and every time the pump volume delivered and the tank reading correlate to within a very few litres so I would be surprised if Mike's difference is down to being shafted by fuel suppliers There must be another reason, as you say, possibly a recording error

But mike you are comparing the retailer's pump reading with your tank (pressure transducer) gauge, not with the ECU.

(It's good to know your tank gauge is good though!)

 

[jfm]

% engine load is very useful on sea trials with new vessel, however gives me the ab dabs when I see WOT numbers in the high 90% at WOT when vessel is clean, what people seem to forget is the fact that system cannot display engine overload. Once you get 100% load display will continue to show 100% even if engine is running at say 150% load.

How do you get 150%? Does the ECM demand an injection time (PWM) of greater than the maximum? Surely that is a software matter: the ECM programmer can make sure the PWM is never longer than the 100% figure. Thus, if the thing is overloaded say because of too-coarse props, it just fails to reach the correct rpm value at WOT and 100% load.

Come to think of it, isn't the definition of WOT on a diesel (which as we both know has no throttle!) is when the ECM demands the longest injection event/PWM that the software permits, and then will read 100% load factor on the display, sort of by definition?

Happy to be corrected if misunderstnading

 

[Deleted User YDKXO]

(It's good to know your tank gauge is good though!)

Even better to know I'm not being conned!

 

[Hurricane]

I'm wondering if perhaps you have could have missed out one fill up in your listing that adds up to 91195.

Nop, - I'm 100% sure of my fill ups.
It all goes into a "ships log" - every long passage - every mile is accounted in the log.
All done in retrospect but I'm 100% sure of the data that I record manually.

EDIT
Actually, thinking about it there was one fill up that was a bit dubious - in Tunisia we had three of these - only had their word for it that they contained 1000 litres each - no gauge - in fact no nozzle on the hose either!!!
3000 litres was recorded in my log though so it wouldn't have made that much difference.

Actually doing the sums the actual fuel consumption is still less than 5% difference to that of the electronics.