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serious 60 rough idle when warm - wellrun - 02-23-2019
got a 1998 12.7 ddec4 that had jake and performance problems....removed did valve cover and saw damage springs 0n#1and broken snapring and damage washer on #2....#1and #3 solenoids were also leaking oil when manually activated ............also ran an overhead didnt do injectors...
engine sounds great after start and after it got warmed up when i was rev jaking it began idling rough and act as if there a bad injector or compression..backfires a little too..sounds af if the jakes were still on.
question....can bad solenoid cause oil to leak pass and activate the jake?
RE: serious 60 rough idle when warm - Chamberpains - 02-24-2019
Did you replace all the jake solenoids? Also, what spring was damaged? Did you pull a solenoid apart (solenoid springs are inside the solenoid housing) or did you just see 1 of the valve springs and retainer snap rings broken and busted up. Cause if thats the case, you have a broken valve spring and the valve is not closing all the way. Its mis firing because you are flirting with dropping a valve in the cylinder.
Something happened to damage the overhead components. More than likely a careless mechanic forgot something in the overhead last time it was opened up, flat worn out overhead parts or one of the valve buttons or cages broke loose and flew around busting everything it can till it finally found its way down an oil gallery to the oil pan. You need to open it back up and reevaluate the damage and fix it.
And to answer your solenoid question, yes they fail open some times and oil will pass thru causing rough operating.
RE: serious 60 rough idle when warm - wellrun - 02-24-2019
could answer....when i was doing the overhead i saw a piece of broken part that look like it came off the valve adjusting screw top.....check all mine and they were good,soo it looked like it had a major damage some time before...will change solenoids tomorrow a see whats next
RE: serious 60 rough idle when warm - wellrun - 02-24-2019
the inner spring was damage one the #1 jake housing.... and the second housing had damage washer and snapring broken...it not the valve spring that was broken..its the jake springs
RE: serious 60 rough idle when warm - Chamberpains - 02-24-2019
We can definitely tell you whats up with a couple pictures of the broken pieces, good angles of the whole overhead and the damage. Quite a few of us on here have worked extensively with these engines.
The solenoids are easy to change. They just screw in and torqued down. If i remember correctly, the torque value was stamped right on the solenoid.