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The company I work for just recently bought a replacement engine for one our cx613 mack vision trucks. The new motor is out of a 2002 cu600 mack. Its an E-7 427 v-mac iii. While I was inspecting it I noticed an oil line that come off the oil filter housing and t's off to both jake spacers on the heads. The 2001 truck that we have doesn't have this line on it. Is this mack's fix to make the jakes work with lower oil pressure? 

1 minute ago, Mark T said:

Does the engine brake still work ?

No, hasn't worked in at least 10 years. From what I've been told, it hasn't worked since the rod and main bearings were done years ago. 10 years is as long as I personally know the truck. 

1 minute ago, Joey Mack said:

boost loss is not related, I just put that in there because Im seeing 2 issues..

It did get a new air to air last year, and the boost hoses look good. I haven't noticed and strange whistles either. 

1 minute ago, Mark T said:

Check the soft plugs didn't come out of the rocker shafts ?

I can have the shop guys look at that. It's easy enough to pull the valve covers. 

1 minute ago, Joey Mack said:

Black smoke can be a boost leak.. can you pressure test the charge air cooler and intake manifold for leaks?  I would do it just because..  

Like I said, its not excessive smoke. And I don't see how a boost leak would cause low oil pressure unless the turbo was junk. I don't believe that to be the problem as it seams to have decent power. Again, I always feel like nothing ever has enough power. I know a guy with a 379 pete with a fresh overhaul on a c15 cat that rolls way more coal. I realize that's comparing apples to oranges, but my truck smokes about the same as it always has. 

35 minutes ago, Joey Mack said:

so in years past, we would roll rods and mains in and take the oil pump apart and look for scaring grooves inside ,and inspect the relief piston for scratches, and the spring. another thing to look at is the plugs on the end of the rocker shafts.  they can loosen or even pop out. 

I say this, not knowing how good it runs and what color the exhaust is..   If the engine needs a re-build, (rings) then at least you will have the new rods and mains..  It has been a good way to get oil pressure back up. In most of the repair we did, the updated high pressure oil pump was installed..  Jojo

Exhaust is black, but doesn't roll huge amounts of coal. Only for a second or 2 when shifting or starting out from a stop. Seams to run fine, might be down on power a little bit, but that could be me never feeling like anything has enough power. It's never had pistons, rings or sleeves replaced either. 

Hello everyone, I'm looking for some opinions. I drive a 2001 cx613 with an e-7 427. Its the vmac engine with the unipumps. Very recently the oil pressure started to drop while at highway speeds. It usually runs about 40psi, (which I personally think is on the low side, but was told by a dealer that that is normal) but now is down around 20psi. Its about 10 to 15psi at idle, which it always was. The oil in the pan smells really burnt as well. The mechanics and I are thinking the motor is cooked. Its got around 1.6 million miles on it. The rods and mains were done probably 12 years ago or so. Again, just looking for opinions or confirmations. Thanks. 

1 hour ago, Joey Mack said:

Have you done any work in the EUP's?  When the lower o-ring goes bad, it will put fuel in the crankcase..  

If you are not familiar with how to remove and install the EUP'S, come back here and we will guide you.. Jojo

We replaced #3 all together and o-rings on #6. No change. I'm starting to think its injectors because of the raw fuel smell out the stacks. Don't know how to confirm that without yanking them and sending them out to be inspected. 

On 10/4/2023 at 5:56 AM, Joey Mack said:

1st.... Stop using Ether.. does it start back up after it runs for a bit?

Have you pumped the hand primer before starting it to see if you have fuel pressure in the galleries?

Have either the cam or crank sensor been touched before this issue?

No Ether.....

It doesn't matter if it was just running or been shut off all night, no re-start. The primer pump does nothing, I can pump it all day and it doesn't help anything. Replaced the tranfer pump, no change. Checked fuel lines, no leaks. Now it started dumping fuel into the oil pan. Smells like raw fuel out the stacks when its running. Will put a gallon or more of fuel in the oil in 600 miles. 

I drive a 2001 cx613 with an E7-427. The problem I've beem having lately is that it won't start without starting fluid more often than not. I replaced the fuel filters thinking they were dirty but didn't fix the problem. Then I replaced the check valve in the fuel return line on the passanger side of the block. Still not much help. Could the fuel transfer pump be crapping out or should I look elsewhere? Any ideas would be greatly appreciated. Thanks. 

The company I work for has a 1993 ch613 mack with a 400 mack engine. Every 6 months or so a head gasket blows and starts using coolant and overheating. We replace the fire rings when we do the head gaskets but still keeps happening. Does anyone havevany ideas why this keeps happening? Thanks. 

I've got a 2000 cx613 vision sleeper truck. Been driving it for a few months now. There is a switch on the side of the drivers side table in the sleeper. The switch is a rocker switch with what looks to be green stickers on both sides of it. The switch doesn't seem to do anything, so I've been wondering what its purpose is. Could anyone give me any info on this switch? I've attached a picture of the switch. Thanks in advance for any help. 

I'd say the fan robs more than that. With the a/c running, it feels like I'm driving an r model with the econodyne engine. I'll look into that video tho. Thanks. 

Its an e-7 427. But it doesn't seem to make anywhere near that much power. I used to drive an older e-7 427 without the emissions garbage on it and it would climb hills way better and the fan didn't kick on half as much. 

Does anyone know if there is an egr delete kit for a 2006 cx613 with an e-7 engine? The truck seams to be way underpowered. The truck seams to have to work way to hard to climb hills loaded and only gets worse when the fan clutch kicks in. 

I've got a 2000 cx613 vision with an e7 427 at my shop. After years of the Jakes not working we finally solved the problem. It turned out it was the switch on the clutch pedal. Now the issue we have is the jakes dont come on till the engine gets to about 1300 rpm when slowing down and down shifting. This seems a little low to me as when down shifting I go to the next lower gear at 1200 rpm. Has anyone else had this problem and how did you fix it? Is this just the Jakes being out of adjustment, a computer issue or a combination of the two? 

What should a compression gauge read on a 1993 ch 613 mack with an e7 400?

I have a 2001 ch613 mack. The engine doesn't always turn off when you turn the key off the first time. I replaced the ignition switch but that didn't solve the problem. Does anyone have any ideas to point me in the right direction to fix the problem?

I have a 93 ch613, the washer pump doesn't work with the button. I used a power probe and the pump works and also swapped out the switch but it didn't change anything. Is there a separate fuse for the washer pump or is it something in the wiring? Any help would be appreciated. 

I have a 1999 ch613 Mack with an e7 427 engine that keeps blowing the fuse for the ecu when I turn the key to the run position before I even start it. I'm sure it's a short somewhere, but I don't know where to start looking. Could anyone help me?

Thanks again. I know about the install tool as I said, I've done the install a few times, just never pulled one without pulling the flywheel housing. 

I'll give that a try. Thanks. 

I have a 1993 ch 613 mack with a 400 engine. I'm replacing the trans and noticed oil in the flywheel housing, pulled the flywheel and sure enough the rear main seal is leaking. How do i remove the old seal, I've replaced a few on the e7 engines, but was always replacing the flywheel housing also. How do i go about removing the old seal without pulling the flywheel housing off?

The ch613's we have are the same way, but I think the cx613's are electric. 

I've got a 2001 cx613 Mack vision that doesn't switch between defrost, floor, dash and mix. I've replaced the controls but didn't fix the problem. I don't see any burnt or melted wiring. Can anyone point me in the right direction on how to fix this issue?