Re: Surprised to find that I rarely run in 6th gear - what gear do you run in?
Reply #63 –
An ISM is different than a celect plus. the ISM had a ten times higher pressure fuel rail and electronic injectors allowing multiple injection events per firing stroke.
more atomization. quieter. more power.
I am asking as I need correct info to double check mine versus other similar coaches.
if someones m11 celect plus varies a lot from the others his or ours is different.
the internet shows several common failures on m11 celect plus's. one is the oil pressure sender unit. if it fails the ECM stops the motor. if you pull the wires from it after verifying the engine actually has oil pressure the check light will stay on but the motor will start and run.
I am going to have the dealer run a simple test on the other sender as if its incorrect on its signal sending the ECM reduces the fuel flow.
ISM does not work this way. they also have a waste gate turbo the m11 does not have. the m11 reduces the fuel flow to control the turbo boost.
ISM governs the fuel pulse itself electronically as far as I understand it.
so a report on mpg on an identical motor geared the same is good info for me. means I may not have found all the aged parts in the fuel delivery system.
mine runs ok but seems to flatten out as it revs. feels weird to me after driving countless diesels. that got me to search the internet on common m11 celect plus engines.
especially if you search power loss issues.
the sensors partial failure will not light the check light but a too quick of sending a full boost pressure will cause the fuel system to back off the fuel delivery way too early at too low an rpm.
the silver leafs HP indicator is a derived by rpm only number. no actual measuring device is in the system.
if you download the m11 shop manual from scrib'd and go into the trouble shooting area for each sender on the motor you will see the sender and the hookup for a mechanical gauge to verify the actual engines boost.
having the silver leafs indication of the sending units output electronically and the mechanical gauge hooked up next to it allows the only verification that the sender is sending the correct signal to the ECM. known to wear. known to fail.
I hope mine is bad as its an easy cheap fix versus the rest of the possible tests and parts.
its the intake manifiold pressure sending unit. be fun to find one that was wrong the other way where it was slow to report max boost a bit. hmmmmmm.
steinbauer does make a box to add 20% more power by increasing the pulse width of the ISM ECM's signal to the injectors but make nothing for the M11 Celect plus.
too low of a pressure system for much change of the pulse width.
my dyno run showed -50hp at full rpms at the cummins dealer in los angeles. silver leaf showed full 450hp.
the engine btw in the shop manual is actually rated at 420 brake horse power for our cummins parts list.
so the only way to verify things is to do the simple well known issue tests then look deeper.
its not bad just down on power per the dyno. fixed the fuel filter first. now the next step.
I want all that is supposed to be there then will see what is possible. fooling the sender a tiny bit might be a safe, easy mod.
if too much pressure indicated too early reduces power my next thought was the reverse.
would only be a ggod idea if every single part in the engine and trans and cooling system were in verified perfect condition and a boost temp gauge installed. and to use it.
maybe not needed as mine is close even down on power a bit.
from the other comments on power here I assume a fixed engine and a resonator will be great.
your m11 at 8.4 is an anomaly. maybe.
what tires are you running at what tire pressure?
thanks for any info. the shops service writer normally only wants the check engine light to go off per the shop foreman versus a possibly more subtle power loss.
if every one you drive seems the same is that the way they are or does everyone have the same worn part?
especially as the ISM'S all report better power and mpg. maybe its the system. maybe we all have worn inexpensive intake manifold pressure sending units.
similar mileage and use. makes you think.
the $500 worth of dyno times was necessary to verify the total output.
258hp with a bypassed winn system versus 420 minus roughly 20% for power train losses. should be 310 range according to two independent cummins shops at the rear axle on a dyno.
just me. driven too many faster big coaches. something seems incorrect. with the help here I can either find that's its fine or needs fixing.
bob
Topic: Surprised to find that I rarely run in 6th gear - what gear do you run in? (Read 2059 times)
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