CM570 Reman Issues

[micahtristar]

I have a Mack CL700 with an ISX 600. It is a 4 axle truck, factory set up for heavy haul. I bought it used in the summer of last year. I use it to move my equipment and occasionally move equipment for friends. It gets driven on average 4 hours a week if that. Typically very few miles, everything we do is local.

Last year the motor dropped a cylinder liner or something catastrophic and became a non rebuildable engine. I ordered a reman from a Pete dealer near me. In an attempt to save money I had my mechanic swap the engines. The reman engine comes fully dressed minus alternator and a few other small things. It comes with a new ECU.

After he got the engines swapped, he got it to start but couldn't get any throttle pedal. We swapped the ECU to the old engine ECU and everything was good to go except the coolant temp gauge did not work. We jumped the wire to the gauge and off we went.

I did not realize at the time that the truck was underpowered and things weren't right. I was only seeing 20PSI for boost pressure. We fixed several boost leaks and capped the waste gate line off. I now see 30-31PSI max boost pressure. The truck still feels underpowered, and after surfing this forum I believe I am still not achieving the correct boost pressure.

After surfing this forum, I am beginning to think that the old ECU was doctored for a possible demandate? I dont have the old engine any more. I ordered insite and the appropriate cables to connect to the engine. My plan is to install the new ECU and attempt to get the dead pedal to go away. Is there anything else I should look out for? Any pointers on getting the dead pedal to go away with insite? I have never used the program before. What boost pressure should I be seeing with this engine?

PS I do not trust any shops in my area, and prefer to do work in house. I realize now that several mistakes were made. Just trying to get my truck back to 100%. Thank you

[Bengy88]

(10-24-2022 )micahtristar Wrote:  I have a Mack CL700 with an ISX 600. It is a 4 axle truck, factory set up for heavy haul. I bought it used in the summer of last year. I use it to move my equipment and occasionally move equipment for friends. It gets driven on average 4 hours a week if that. Typically very few miles, everything we do is local.

Last year the motor dropped a cylinder liner or something catastrophic and became a non rebuildable engine. I ordered a reman from a Pete dealer near me. In an attempt to save money I had my mechanic swap the engines. The reman engine comes fully dressed minus alternator and a few other small things. It comes with a new ECU.

After he got the engines swapped, he got it to start but couldn't get any throttle pedal. We swapped the ECU to the old engine ECU and everything was good to go except the coolant temp gauge did not work. We jumped the wire to the gauge and off we went.

I did not realize at the time that the truck was underpowered and things weren't right. I was only seeing 20PSI for boost pressure. We fixed several boost leaks and capped the waste gate line off. I now see 30-31PSI max boost pressure. The truck still feels underpowered, and after surfing this forum I believe I am still not achieving the correct boost pressure.

After surfing this forum, I am beginning to think that the old ECU was doctored for a possible demandate? I dont have the old engine any more. I ordered insite and the appropriate cables to connect to the engine. My plan is to install the new ECU and attempt to get the dead pedal to go away. Is there anything else I should look out for? Any pointers on getting the dead pedal to go away with insite? I have never used the program before. What boost pressure should I be seeing with this engine?

PS I do not trust any shops in my area, and prefer to do work in house. I realize now that several mistakes were made. Just trying to get my truck back to 100%. Thank you

Pm me your contact info ill help you get her figured out

[Rawze]

A cm570 has no egr or dpf form the factory so it only needs a factory program to properly run it. f you suspect some modified program then take it to a stealers$it andhave the ecm re-flashed with the proper program for that make/model truck and engine.

NEXT.. you stated a big no-no!!. That Waste-gate NEEDS TO BE SET PROPERLY.. AT 35-36 PSI BOOST MAXIMUM!!.. or you will kill that engine once you have solved your low-boost issues.

NEXT:.... if it is getting low boost.. then pressurize everything and fix all the boost leaks, etc.. and than take it on a test drive with the Insite software connected to it and monitor the fuel control state. It is the FUEL BEING HELD BACK and not the boost. The ecm will tell you exactly why.


LASTLY.. FIX THAT GADD@#AMN COOLANT TEMP SENSOR PROBLEM!!! --- That thing gets hot or has a coolant issue then you will destroy your $40,000 commercial engine because you will not notice it until tit is too late!!!>. This was absolutely the wrong thing to do!.

I HAVE SEEN AT LEAST 10+ PEOPLE over the years completely and utterly regret bypassing coolant sensors because it bit them in the arsse out of nowhere one day, and loose their engine over it.

So.. yeah,. I am that guy who is going to point those things out ... so that someone does not do this kind of stuffs because in about 5 years from now and everyone forgot by then that you bypassed coolant sensors and/or bypassed the boost pressure regulator, and a failure occurs over it, I can say.. that you were warned.

[micahtristar]

Sorry, what I meant was that we jumped a wire directly to the gauge in order to read coolant temp. The ECU must be seeing coolant temp however because the fan runs as it is supposed to.

And yes I realize the mistakes were made now that I have begun researching further. My intention is to get the truck running on the new untouched ECU that came with the new motor and repair the wastegate line. Because I have no idea what was done to the previous ECU. The truck is a 2001 I believe so there is no telling what "tuning" previous owners may have done.

[hhow55]

When Mr Hagg looked at mine, he told me max boost is about 20. I do my best to keep it at 10 when running for good fuel mileage. And yes it is cm570

[Bengy88]

Hmmm 20 psi max? Im not doubting Mr Hagg i hear nothing but good about him but ive never heard that about any diesel engine. Would anyone be willing to explain further just because i cant just say ok and leave shi#t at that? Im not trying to be a clock builder i just gotta understand how shi#t works to better myself.

[Rawze]

(10-26-2022 )hhow55 Wrote:  When Mr Hagg looked at mine, he told me max boost is about 20. I do my best to keep it at 10 when running for good fuel mileage. And yes it is cm570

The max boost for a CM570 is about 35-36 psi (37 max) at 600HP.

in the service manuals.. it generally says to refer to the specific engine make/model data-sheets...

(just an example.. not engine specific)...


However ... those are not so easily obtained.

CM570: To be even more precise, most of the old Engine performance datasheets (from cummins) for them (CPL 2442 = Sig. 600) used to show "Prime (optimal) power production" is a minimum of 33 psi as achieving the highest efficiency before any power loss occurs when turning 1750 RPM. <- only issue with making one run this low of boost levels is that the exhaust runs a bit too hot long term for most waste-gated turbochargers .. hence,.. the 35-36 PSI rating after considering the turbochargers needs as well.


On slightly newer model engines like the CM870 and the CM871, they used to always list the pressures that include controlling exhaust temp considerations due to the VGT turbocharger and its temperature ratings. Sig-600 CM870's and for most CM871's above 515HP, they all show that "Prime (optimal) power production" is now at 37.4 psi as achieving the highest efficiency before any power loss occurs when turning 1750 RPM. This number also does not consider the inflated boost value due to added 'EGR' pressures either... so it infers that it is still 35-36 PSI on those model engines?, but I doubt it. - Much dyno testing however has been done over the years and we know what a de-mandated CM870 or CM871 engine needs about 36-37~ish PSI optimally, 38 max.

On a non-deleted engine, this should be be about 38-39~psi or so due to EGR gas artificially raising the intake pressures. This has been observed time and again by testing and during troubleshooting of these engines. This clearly shows that up to about about 2 psi of intake pressure is the EGR gas itself, and NOT due to only the turbocharger.

On the CM2250 and newer model common rail engines, it gets murky. They seemed to have stopped making/providing detailed datasheets and Prime Power production publications for these engines that included all the extra info. Details like compression ratio, intake boost, and the other things that they used to list are now missing. Finding those specs is difficult and obscure.. though there have been a few advertisements running around the interwebs that have show some of this data here and there in the past.


In any event.. on ALL MODEL ISX engines, assuming that it has been de-mandated (no more egr gas) ... the proper boost level can be actually determined by measuring the post-turbo EGT's. Assuming for a moment that the injection timing + all other settings have been corrected 100% properly for that type of operation (as 90% of all programs are not ) .. and ...

assuming there is 100% absolutely nothing wrong with the engine including boost leaks, restrictions, any engine issues, etc...

At a sustained 100% throttle position, and at an RPM of 1650 - 1750 ... the EGT's should be about 1050 - 1100.F.

If it is very much out of this range (POST TURBO) .. then the boost level for the engine is either too high (lower then normal EGT's, like only ever able to get to about 900~ish) or too low (higher than normal EGT's, like say can get to 1200+).

Again though.. out of bounds EGT's does not mean your turbo is adjusted improperly.. maybe someone has engine or other issues.. as most engine should be adjusted properly to begin with .. but it is one consideration when someone just does not know the answers.

This is why we know what the boost levels should be for the various ISX models out there.. much testing has gotten that proper information... so here it is (roughly) again ...
---
(Since all 570 overhaul kits are now 17.6(tier2) or 17.1(tier1) ratio .. ) CM570, Waste-gate at 35-36 psi for most and max is 37-PSI for a 600HP model on the intake at full operating load.

CM870, 871... 36-37 PSI for most engines, and 37~ish, 38 max for a 600HP model.

CM2250, no more than 36 PSI at 600HP+.

CM2350, no more than 33-34~psi at 600HP.

CM2350-X15, Not more than about 32~33PSI at 600HP.

The pressures keep dropping off from one model to the next because they keep raising compression ratio of these engines from one model the the next. This also shows up when testing them.

---
The trouble is that too many people have bad/improper delete programming, so this info is mostly useless for the 90% of people who would read this that are running around out there with deleted engines.


In the case of the CM570... these same numbers should also hold true.

===========
Maybe Mr. Hag was referring to how someone should be driving it for optimal fuel mileage?>..

It is mentioned many times on this forum for people, if they can manage to drive it and keep the boost down to 20 or so by controlling their right foot, .. it will fair much better in fuel mileage.

[Bengy88]

I greatly appreciate you sharing that with us

[hhow55]

Thanks for sharing, Mr Rawze...........I stand corrected