2001 Mack E7 engine brake

[bobgil]

I have put the 01 CX to work now and it seams to be doing ok I have not had any thing over 30,000 behind it yet.

In the 2000 miles I have driven it I am liking a lot of the truck but I am more than concerned about the engine brake. It does not seam to be doing much more than making noise. I went down ranger hill on I -20 in Texas, not a big hill but about all I have had to deal with since getting the truck. The engine brake did not seam to do anything at all. With my gross weight less than 40,000 lbs I would have been at the same speed at the bottom as the top in the T800 with the cummins in it that I have been driving.

Came the Mack engine be adjusted to work as well as the jake on the cummins? I will probably be running on the Heavey side a good bite of the time and running thur the Midwest and north and I would like to have the extra braking power.

I have been offered a load coming out of Calgary AB going to Houston grossing about 95,000 lbs and the extra braking power would help a lot north od Cheyenne.

Bob

[wheeler73]

If it is a Jacobs set up it may need to be rebuilt or updated. The Jacobs set up in my opinion is mostly a noise maker on a Mack. The power leash on the ASET engines works great.

[bts-4120]

jake on the e7 will never be what a jake on a n-14 is due to cubic inches. mine helps some but at a 95k gross you will be using your truck and trailer brakes getting down a mountain no doubt about it

[bobgil]

I am not sure what the T800 had in it but it was a 2012 model don't think it was a n 14.

I am assuming that the engine brake on the E7 is not adjustable then I am still wondering if mine is working on both heads because it doesn't seam to make any noise when in the low mode

[DCR]

There is a supplemental oil line that can be added to get more oil to the Jake. It comes off of one of the oil filter housings and goes to the Jake heads. I had this done to my E7 460 and it helped a little. I also added 2 gallons of Lucas on next oil change and it improved oil pressure by 10 lbs. and greatly increased performance of the Jake. Prior to Lucas, I would have to apply some brake going down Snowshoe on I80. After Lucas, Jake would hold my speed or I would even have to add throttle to reach the bottom, pending weight of load.

[bobgil]

Ok it seams like I need to research that added oil line. I was thinking that the engine brake was adjustable like the valves and only electricity activated.

Thanks for the reply

[wheeler73]

They are adjusted when the valves are adjusted. When you have them adjusted make sure to have the Jake pins checked and adjusted also. If they are worn like most I see are have them replaced. If you don't hear or feel anything on low you can apply power to the Jake at the box and see if it is working. If not it may be a bad solenoid.