CM870

[JLDees]

Greetings all,

New to the site I am currently in the process of upgrading trucks, Looking at an 07 W900L with a CM870 with 750K on the clock, in the photos it looks like it has the factory egr cooler and the turbo looks like its been replaced. No history on the engine, salesman says "all original" Now what I have in my mind is I plan to replace the EGR Cooler, Belt Tensioners, Water Pump, Fan Hub (Unless feels smooth) and an EGR tuneup/cleanup. There are some differences in the videos of Rawze's cm871 Tuneup series on youtube, this one has the swelled down venture with the EGR hose in front of the compressor intake (worries me if its pumped soot in the air tanks) and the intake elbow looks like it has 2 sensors I'm assuming Delta T/P and IMAP but they look different than the later cm871s (Images attached). I plan on asking if they will do oil samples, but if its had a recent PM that might not show what I need to know, If not ill pull the valve cover in person to look at the cams, rollers rockers etc. and see how clean it is.

Option 2 is an 08 W900L similar spec same miles with a cm871 that has been "mandate'd" with the same miles that is being sold by the owner but I haven't got ahold of him yet. I am leaning towards the 07 for the specs, and closer to go get.

Application for the truck, It is replacing my 79 Extended Hood W900A with a late B model ATAAC 3406B which I hate to see go as it runs like a clock and has never let me down, The truck however at 38 years old the air and electrical systems are wearing my patience. I only turn 20-30k miles per year doing various things, I pull my demo end dump and belly dump for a local quarry, Heavy Haul (my own equipment for dirt work business) and my own products Log Home Kits, Rough Lumber etc. I Live at 9000ft elevation and make frequent pulls and descents on our 16 mile 6% grade along with several other hard pulls throughout Colorado and NM

Main questions are the sensors on the cm870 mentioned above and if anyone has a similar setup and if there is a pipe within the venture for the compressor to keep it from sucking soot. And what other sensors on the cm870 would I be smart to carry? Thanks in advance

Josh

[Rawze]

There is no single IMAP sensor on the CM870. The sensors on the intake you have circled are the intake pressure and intake temp sensors.

Go to quickserv.com and register the enigne ser# and you can get a breakdown of the entire engine.

[marek4792]

The egr pipe actually goes in past the compressor intake inlet and the two sensors you circled are the intake temperature and boost pressure sensors and something not to overlook is the exhaust pressure sensor mounted to the thermostat housing the little metal pipe going from it to the exhaust manifold will clog up once in awhile. There's actually a couple sites where you can also get a new intake manifold that isn't constricted if you're looking to tune it for big power.

[JLDees]

(01-01-2017 )Rawze Wrote:  There is no single IMAP sensor on the CM870. The sensors on the intake you have circled are the intake pressure and intake temp sensors.

Go to quickserv.com and register the enigne ser# and you can get a breakdown of the entire engine.

Thanks Rawze, with the internal piping marek4792 mentioned do these sensors have the plugging issues of the cm871s? Hows your engine been since the inframe?

[JLDees]

(01-01-2017 )marek4792 Wrote:  The egr pipe actually goes in past the compressor intake inlet and the two sensors you circled are the intake temperature and boost pressure sensors and something not to overlook is the exhaust pressure sensor mounted to the thermostat housing the little metal pipe going from it to the exhaust manifold will clog up once in awhile. There's actually a couple sites where you can also get a new intake manifold that isn't constricted if you're looking to tune it for big power.

Thanks, Ive seen a few with those on them and wondered where they came from, Both trucks are set 550hp and 1850tq, going from my 425hp b model I think ill be more than happy with 550. Planning on carrying the two circled sensors and the back pressure sensor that little pipe runs to.

[JLDees]

(01-01-2017 )JLDees Wrote:  

(01-01-2017 )Rawze Wrote:  There is no single IMAP sensor on the CM870. The sensors on the intake you have circled are the intake pressure and intake temp sensors.

Go to quickserv.com and register the enigne ser# and you can get a breakdown of the entire engine.

Thanks Rawze, with the internal piping marek4792 mentioned do these sensors have the plugging issues of the cm871s? Hows your engine been since the inframe?

I read that wrong I thought he meant the pipe ran past the sensors so disregard that question, As its equipped with a factory boost gauge would I see erratic readings on the gauge if the pressure sensor was plugged?

[05ISX450]

I also have a CM870, do yourself a favor, and have Gearhead go through the motor, including an overhead adjustment, I would also put on a new crank damper. It is recommended at 500K. I used a Vibratech on mine. My 870 has never run better thanks to Gearhead. Good luck.

[Rawze]

(01-01-2017 )JLDees Wrote:  would I see erratic readings on the gauge if the pressure sensor was plugged?

Not necessarily. they do not clog as frequently as the CM871's do, but they do read incorrectly as they age. Replacing old engine sensors along with other tune-up work is cheap insurance to make sure you are getting good feedback to the ECM.

Also, it is very easy for someone to put the wrong file in an ISX when they change the HP ratings. Though it is mostly talking about the CM871, Here is a bit more on this.
http://rawze.com/forums/showthread.php?tid=1&pid=1#pid1

[JLDees]

Thanks that makes sense, I think ill be more than happy with 550hp and 400+ extra ft lbs of torque over my b model which I've run stock for 8 years and never touched the fuel screws, thought about it but never have.

One other question I forgot, I drove a 9200i International with a cm870 about a year ago and it had a second or so delay with the jake response which really bothered me, is there any way to change the response?