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JimmySignature

To Inframe or Not to Inframe

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Hello all,

I recently purchased a 2003 CH613 with an E-7 (pre-emissions) to get started in trucking.  I have no experience and I usually attend the school of hard knocks and teach myself as long as it is safe.  A friend of mine has some extra work from time to time and I have always wanted to get into trucking, he offered to ride with me and show me the ropes when he is not busy.  I am an auto tech and fabricator by trade, no diesel experience.  

The truck has 900,000 miles on it and a miss when it is cold.  I got it for a good deal and it is in nice shape.  I noticed when the truck warms up it idles well (possibly eliminates the miss) and hold 20# on the oil pressure.  There is significant blowby from the tube under the engine and it looks like clear water that drips...... I am guessing that is condensation from the excessive blowby.  No visible water in the oil, and goes down the road well.  I was thinking that if it pulls OK enough for a rookie under load I might be able to push off a rebuild for a while.  My rookie question is obviously this truck needs an inframe but when is it mandatory.  The previous owner says it doesn't use oil but then again I was handing him a stack of cash....

Can DOT get me for blowby (there are steady puffs from the tube at idle)?? 

If the engine runs cool and has good oil pressure am I doing other damage? 

Is there a good trick to verify the miss when warm?.... I can't just disable the spark plug lol, or use my snap on scan tool to kill the injector and watch my RPMs

Could something be making this blowby worse than it is?  I read about other things that causing high crankcase pressure, obviously, the 900k is the major concern.

I know the inframe is going to be expensive even if I try and do it myself and it will, of course, open a bigger can of worms than I can possibly plan for.  I am just curious if I can drive it for a few months learn a little about the business and maybe save up some money.

Great Info on here.... This site convinced me to buy a MACK

 

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Thanks for the reply.  I will put the blowby aside for now... I appreciate you giving me a clear path on that.

Is there a good company to run the oil sample??

I had the lightning bolt on the dash and got some codes 8-3 and 8-5 late last night after I read about the cruise control trick on here!  Checked it again this morning and had 8-1, 8-2, 8-3, 8-5.  I will try to short out the terminals in the morning as you suggested, to try and find the dead cylinder.  Curious if these eup codes matter on a cold old engine.

Another quick question.  Seems like only the rear passenger tire is spinning (almost like I am on ice) when I was trying to pull up a very very slight incline into my shop.  I used the power divider to get in.  Almost seemed like it got worse as the airbags filled up.  Broken axle in the front tandem maybe ??

Thanks

Jimmy

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14 minutes ago, JimmySignature said:

Another quick question.  Seems like only the rear passenger tire is spinning (almost like I am on ice) when I was trying to pull up a very very slight incline into my shop.  I used the power divider to get in.  Almost seemed like it got worse as the airbags filled up.  Broken axle in the front tandem maybe ??

Thanks

Jimmy

No broken axle...the diff will let one wheel spin when it doesn't have traction. That's normal.

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If you've got the Henderson air ride suspension, it's notorious for that. I drove a '99 CH tandem tractor for a while that would light up the "traction control" idiot light anytime you took a corner halfway fast when running light.

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Only thing to pay attention to is someone screwing up the suspension assemblies. I'm working on a truck right now that sits crooked. When you look at the Z-spring members it doesn't even touch the front hanger on the RFRear, I can stick my fingers in the gap between the spring front slipper pad and spring strike-side. Whoever did the spring work put the wrong spacer in between axle and spring member. One side spring spacer is tapered for caster and opposite side is perfectly flat and square. In the case of what I have you can get an uneven load to one wheel, esp when bobtail.

In the mid/early 2000’s Mack over sensitized the fault parameters and we occasionally got ghost codes on working EUP’s. It seemed to have come in with the CCRS vintages. They changed the software to lessen, or desensitize, the ghost code issue/parameter. If you change the EUPs the codes will likely disappear, but I’d require them to show a running issue before changing out. Example-your cold miss could be a failing magnet in the specific EUP your coding on and justify a new one. Aftermarket vendors are selling those pumps cheap, so it may be a worthwhile investment. 

Edited by Mack Technician

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Thanks for the ideas on the suspension, if some of this is normal how do you guys bobtail these trucks?  I have been told not to use the power divider but without it, I can hardly move this truck in the yard!  The surface is dry packed gravel, it even slips real bad on the pavement..... sucks being such a rookie. 

Back to my rough running, missing 900k engine, lol.  I shorted out across the terminal of the number 1 EUP and the truck shut off immediately???.  I cleaned up the terminals and was wondering if there is a simple resistance check across the terminals I can do while the wires are off?  Threw on the Ohm meter on but it was all over the place, at a quick glance a few seemed to be shorted.

Is there a preferred aftermarket part number to replace my 313GC5230M (Found an old Mack invoice that they were all changed about 10 years ago in the truck).  What is a good price for them and which website do you guys like to get them from?

Thanks Again

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www.ksfuel.com 

 

if you have the OEM part number call a PAI dealer and you can also save 20%-30%

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Thanks, I will give them a call.  Any further help testing the EUP's, not sure if my previous post made sense of shorting them out and the truck cutting completely off??  I don't want to just randomly replace them, the codes on the dash seem inconsistent which makes sense based on your previous explanation of them be overly sensitive.  I would like to ID the bad ones and swap em out.

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Clueless.....I short them constantly at work and never kill a healthy, running, engine beyond the target cylinder.  Are you contacting them to each other or to a dead ground? 

Break them(terminals) loose at one side and retighten lightly so you can use the one wire to remove and dead out cylinder. Keep in mind these terminals get seized easily, if they won’t loosen, don’t force them. 

I don’t have the resistance spec available....I’m not at work. Keep in mind you need to disconnect one side of the EUP to get a legitimate, clean, reading. Otherwise you are including a harness and ECU in your math. 

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I got all of them loose and cleaned them up.  I was placing a jumper wire across the 2 terminals on an individual EUP.  When I did this the truck stalled.  I did not touch any terminals to a dead ground. 

I just tried what you said about slipping of the terminal at idle and it seems like #2 for sure is not doing much if anything, the other ones I can hear / feel a difference when removed.  Seems like #2 may be contributing but slightly.  When I pull the wire off the terminal does that shut fuel down completely or just lower down the pressure??  When the truck is a 1000 rpm I can hold it and the miss is far worse, it shakes the cab.  If I could hold it steady and check it at that RPM I may have a more clear cut answer of what cylinders are not pulling their weight.  

Thanks Again

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I use the power divider frequently

I have been told not to use it any more than necessary on dry pavement and never engage the power divider when the truck is moving

60f4b6e4d650a27554a7c45235259403.jpg

I have a 1989 truck with 25,000 miles on it with the Hendrickson four spring suspension on it and it would spin a tire on the driveway and not move until I locked the power divider when it was empty. This problem went a way when we replaced the suspension bushings, they were cracked and seized from lack of use.

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When there’s no power to the EUP you will flow-through an open center. IOW- If your running 80 psi in your fuel rail...that’s the amount of pressure against the injector tip. If a tip leaks or cracks you get rail flow into the cylinder and lotsa smoke. Injection doesn’t occur till the 80 PSI fuel is trapped & compressed when the magnet induces port closure. 

Edited by Mack Technician

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50 minutes ago, Quickfarms said:

I use the power divider frequently

I have been told not to use it any more than necessary on dry pavement and never engage the power divider when the truck is moving

60f4b6e4d650a27554a7c45235259403.jpg

I have a 1989 truck with 25,000 miles on it with the Hendrickson four spring suspension on it and it would spin a tire on the driveway and not move until I locked the power divider when it was empty. This problem went a way when we replaced the suspension bushings, they were cracked and seized from lack of use.

If you are going slow before you get into something slick you can engage power divider, you just can't engage when wheels are spinning that is where you have to come to a stop and engage the divider.   I have done this for 40 years on macks and no divider troubles.     terry

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10 minutes ago, terry said:

If you are going slow before you get into something slick you can engage power divider, you just can't engage when wheels are spinning that is where you have to come to a stop and engage the divider.   I have done this for 40 years on macks and no divider troubles.     terry

Agree; if you think you might need it put in before spinning; same goes for 4wd vehicles. Saves you trouble 

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I have seen quite a few over the road trucks in which it looks like you can't lock to power divider

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