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+--- Thread: Isx cm2250 engine brake choppy (/showthread.php?tid=2800)
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Isx cm2250 engine brake choppy - aaronb - 02-23-2018
Sometimes my engine brake isn’t working right. It’s not working on all cylinders. I had read that it’s probably either one of the solenoids or the harness. How do I test the solenoids to see if it’s one of them? Is there anything else to look at that might be causing this issue? It doesn’t do it all the time. It does seem more frequent though. Thanks.
RE: Isx cm2250 engine brake choppy - redbeard - 02-24-2018
My 2250 is very sensitive to oil level. If it is a gallon low or dirty, jake suffered.
I now change my oil at 12000. I used to go to 15000.
Adding 8 dimes to the oil pump made all the difference, now at the 42psi. Jake works great. Was at 29psi going down the road before the dimes addition
RE: Isx cm2250 engine brake choppy - Hammerhead - 02-24-2018
How many miles on the unit aaronb?
Demandated or not?
Bypass filter or not?
Oil change interval?
It could be several things;
It could be soot saturated oil clogging up the oil galleries in the Jake system,
Soot saturated oil may also have stuck one or more of the Pistons on the Jake rockers,
The solenoids may be sticking or giving issues,
The Jake wiring harness and/or connectors may be going bad causing intermittent solenoid firing,
It could be worn detents and check valves in the rocker shafts, combined with weak springs in the Jake rockers,
Weak oil pressure makes that last one way worse,
Could be due or way overdue overhead adjustment,
Worst case scenario, the valve cam may be losing a lobe and about to cause a whole lot more and bigger issues.
The best way to find out is to pop the rocker cover and start inspecting things...
(02-23-2018 )aaronb Wrote: ... How do I test the solenoids to see if it’s one of them?
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RE: Isx cm2250 engine brake choppy - aaronb - 02-24-2018
(02-24-2018 )Hammerhead Wrote: How many miles on the unit aaronb?
Demandated or not?
Bypass filter or not?
Oil change interval?
It could be several things;
It could be soot saturated oil clogging up the oil galleries in the Jake system,
Soot saturated oil may also have stuck one or more of the Pistons on the Jake rockers,
The solenoids may be sticking or giving issues,
The Jake wiring harness and/or connectors may be going bad causing intermittent solenoid firing,
It could be worn detents and check valves in the rocker shafts, combined with weak springs in the Jake rockers,
Weak oil pressure makes that last one way worse,
Could be due or way overdue overhead adjustment,
Worst case scenario, the valve cam may be losing a lobe and about to cause a whole lot more and bigger issues.
The best way to find out is to pop the rocker cover and start inspecting things...(02-23-2018 )aaronb Wrote: ... How do I test the solenoids to see if it’s one of them?
The truck has 699,000 miles. The engine was rebuilt at 482,000. I'm not sure the reason for the rebuild. It still has the mandate. No bypass filter installed yet. I just bought the truck a couple months ago. I know the previous owner was running 20,000 mile oil changes. The overhead was just ran about 20,000 miles ago. I was driving the truck and bought from my boss. I'm planning on running the oil changes at 12,000 to 15,000 miles and adding a bypass filter. I'll try solenoid first and go from there. We're having freezing rain today and I don't have a shop to work in. Might be next weekend before I get a chance to check it out. Thanks.
RE: Isx cm2250 engine brake choppy - Hammerhead - 02-25-2018
(02-24-2018 )aaronb Wrote: The truck has 699,000 miles. The engine was rebuilt at 482,000. I'm not sure the reason for the rebuild. It still has the mandate. No bypass filter installed yet. I just bought the truck a couple months ago. I know the previous owner was running 20,000 mile oil changes. The overhead was just ran about 20,000 miles ago. I was driving the truck and bought from my boss. I'm planning on running the oil changes at 12,000 to 15,000 miles and adding a bypass filter. I'll try solenoid first and go from there. We're having freezing rain today and I don't have a shop to work in. Might be next weekend before I get a chance to check it out. Thanks.
I would expect the 20k mile oil changes in a mandated engine to be the cause...
The effects could be many, but I'd almost expect that you have soot saturated oil partially blocking things in the Jake oil circuit...even if this isn't the current problem, it will become one.
I would highly recommend at least two 5k mile quick oil changes to try cleaning out some of the sludge that undoubtedly has built up inside your engine.
If/when you pop your rocker cover to inspect/find your problem, even if it's something as simple as a broken wiring harness...I highly recommend that you pull both valve rocker shafts, disassemble them, use copious amount of brake clean, and clean out all of the oil galleries in the shafts and the rocker arm! There is probably a good amount of gunk built up in there.
With that many miles on the engine, unless the rocker shafts and some or all of the rockers were changed when rebuilt (doubtful), I'm fairly certain that your rocker shaft detent holes will be oblonged and the rocker shafts changed. If/when you change these, also change the check valves and the springs in the rocker shafts. The check valves seat into the detent holes, and if one is worn, so is the other. The springs will be weak after that many miles.
I used to have a thread on the forum describing this procedure, and pictures showing worn vs new parts and new vs old springs. Unfortunately it was one of the threads lost in the last crash. I believe I still have a set of worn parts at the shop that I can post pics of when I get back later in the week if I have time...
When the oil is cooler it is thicker and can overcome the leakage from worn detents and check valves. When it get hotter and thinner too much leaks out the worn surfaces causing erratic response. This is where shimming an oil pump can mask the issue as I previously stated.
With a mandated engine with NO bypass filter, you should be doing 10k oil changes and don't even think about more than 12k when you get your bypass filter put on.
RE: Isx cm2250 engine brake choppy - Ragindirt - 02-25-2018
I see that with my 2010 871, Jake's suffer after about 10k plus, and starts making more valve train noise.
Now that being said not wanting to jack this post; can one who is fixing to do an mm, plus roll new bearing flush the engine a few weeks prior to work.
My thought was drain the oil, hook up a small pump to oil pan with a filter, then circulate back through oil filter housing.
What product go use, or if it would even work eludes me. Was thinking that my wife could kick it on once a day for an hour while I am gone, friggen things is nasty inside and I change between 12/15k.
RE: Isx cm2250 engine brake choppy - aaronb - 02-27-2018
I'll see what I can do on all of that when I get the valve cover off. It doesn't seem to matter if it's first thing in the morning when the engine oil is cooler. Right after an oil change it still does it. It's doing it most of the time but just randomly works fine. That's why I was just thinking it's a solenoid. I have about 6000 miles on the oil so I'll get the stuff to change it this weekend. The oil doesn't look overly black at this point though. I'm hoping to have an amsoil bypass filter in the next few weeks to install. I'll get an oil sample at that point to see how things are looking. Thanks again.
RE: Isx cm2250 engine brake choppy - aaronb - 02-28-2018
I had just enough time to test the solenoid yesterday. One was at 11.1 and the other 11.3 ohms. I forgot to inspect the camshaft so I'll have to look at it when I have the cover back off. It looked ok when the overhead was done a couple months ago. The engine feels smooth except for the engine brake. I'd guess I'd notice a cam issue when under power as well.
RE: Isx cm2250 engine brake choppy - aaronb - 02-28-2018
I did notice on the engine brake that it's smooth above 1500 rpm. It seems right at 1500 rpm and below is when it is acting up.