ISX 600 Engine brake

[mHolc]

(05-30-2016 )Unilevers Wrote:  there is a setting in the ecm for jake delay - if it is set to zero they should come on immediately.

under the cover there are 2 solenoids and a harness, they are very forgot about pieces. If the solenoids are wore (fairly certain they are) they have a delay to them. if the jake rockers themselves are wore, the jake can do funny things. if the harness is kinda bad, it can cause jake delay. all these need to be checked by someone who has experience in these. this is fairly common - the jakes should be instant without delay if the delay is set at 0. How much boost does it build under full jake? that explains alot also.

one last thing to check is the oil and sludge buildup in the rocker drillings themselves. if they are plugged up or the wrong oil is used jakes will be delayed aswell - just food for though

Ok thanks for the response
I got the truck with 250k miles. Truck was well maintained. Well it looks that way anyway. Very clean truck, and guy sent it to yhe dealer and had a few things replaced before we bought it so it was right. But the jack delay they say has always been like that since they can remember. I noticed the 2-3 setting no difference when playing around with it while driving. I cant feel any difference when i switch it. Our Cats u can clearly feel and hear it. But they aren't emission motors. Anyways can i reuse the valve cover gasket if i pull it off just to take a look to see if its a wiring issue or looks sludged up? We've been running Shell Rotella 15/40 in it. Thats what we run in everything we have. Im assuming the guy we got it from to also uses the same or something similar since he has Cat heavy equipment.?
Thanks