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+--- Thread: A few issues (/showthread.php?tid=774)
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A few issues - chaos2law - 08-19-2016
Hey guys, figured I consult the forum of knowledge on isx's. So about 20k miles ago I changed a leaking injector, thing ran great and got rid of the smoke. Now I'm smoking again (black grayish) under load and my engine break isn't working like before. It's much quieter, takes a few more seconds to really engage and build boost pressure. Once it builds pressure it's still less powerful than before and quieter. Any thoughts?
Second issue, this just started happening last two times at speedco. I get a full pm, and I end up having to purge air from the compu-check nipples on the ifsm to get the thing to steady out. This is a new issue and didn't happen before... any ideas on these would be greatly appreciated.
RE: A few issues - trdodd07 - 08-19-2016
Might need to pull the cover and check for any damage to the harness to the jakes, as I hear it can be pretty easy to break when doing work up top. Also try and run an overhead set to make sure that they are within spec as well. Did you update your injector number in insite? I think it's the trim number?? It will cause issues if you don't, and that may be the cause of the smoke. Hopefully someone will chime in with some more info, but hopefully this will help.
RE: A few issues - Hammerhead - 08-20-2016
If the Jakes have a small delay, or "take a second or so" to "build pressure" (I'm referring to hydraulic pressure, not boost pressure) or doesn't sound like every cylinder engages at the same time, it is very possible that;
a)the detent holes in the valve rocker shafts are worn
b)the check valves in the Jake rockers are worn
c)a combination of both
d)the springs are weak in the Jake rocker arms are too weak, MOST LIKELY NON ELECTRICAL CULPRIT
e)all of the above
When the Jakes are activated, oil flows through the rocker shafts and into the Jake rockers via these check valves. When they get worn, or when the springs get weak, it allows some oil leakage delaying Jake engagement of one or multiple cylinders.
Read this post below, copied from another thread, and read the link where I discuss in detail the procedure as I learned about this issue myself, with a little help from the resident experts along the way...
(08-10-2016 )Hammerhead Wrote: Can you more clearly define the knocking sound?
When you say "goes away when the Jake is on, are you sure or is it being masked by the noise of the Jake?
Do your Jakes "instant on full pressure" or do they "build pressure in a second or so"?
I reffered to mine as a "tapping" that also went away when the Jake was on. The reason mine went away when the Jake was engaged was because it was worn detent holes in the rocker shafts. The check valves were also worn, and the Jake springs had compressed a little over 1/4" at about the same mileage. What happens is the Jake rocker does not get held into the detent position and bounces (taps) off the cam.
This is why I believe we should be changing out the springs in the Jake rockers every 200,000 (when most guys run an overhead adjust). They just get weak over time and lead to wear, and I'm convinced that keeping good springs will extend the life of both the check valves and the rocker shafts.
edited to add...this is the link to my corrective action to my sound.
http://rawze.com/forums/showthread.php?tid=557
Key posts are;
6- shows the old and new shafts so you can see the wear on the detent hole
8- advise right from Mr Hagg about the springs, cause I dint know enough to go that far at that time. When you get to that mans shop, shake his hand and say Thank You for me please
14- this is the part number lists for the shaft (front and rear), check valves, and springs (for my engine)
17- an exploded view of one of the shafts and pieces.
18- old spring beside a new one to see the compression over time reduction of spring length
25- a complete list of the results of all the work I did, including the Jake service. I still stand by the statement of "You will not know how badly your Jakes have degraded over time until you complete this service"
Good luck, and keep us informed...
RE: A few issues - chaos2law - 08-21-2016
I appreciate the ideas, I'll be popping the lid as soon as I get home. Was worried about the turbo so I inspected what I could and checked the cold side. Everything looks good, I'll have to pull the actuator off when I get back too.
RE: A few issues - Hammerhead - 08-21-2016
(08-21-2016 )chaos2law Wrote: I appreciate the ideas, I'll be popping the lid as soon as I get home. Was worried about the turbo so I inspected what I could and checked the cold side. Everything looks good, I'll have to pull the actuator off when I get back too.
DO NOT PULL THAT ACTUATOR UNLESS YOU HAVE INSITE!!!
Insite is required in order to properly calibrate the actuator PRIOR to installation. It is highly unlikely you could remove and replace it and get lucky to drop it back on properly. It's not immposible, but it's virtually immprobable, don't take the chance.
RE: A few issues - chaos2law - 08-21-2016
Thanks sir, I have insite and am aware.
I was kinda wondering about the injector trim mentioned above. I was under the impression that the injectors were plug and play, after a good overhead at least. I've never noticed anything in insite for this either?
RE: A few issues - trdodd07 - 08-21-2016
(08-21-2016 )chaos2law Wrote: I was kinda wondering about the injector trim mentioned above. I was under the impression that the injectors were plug and play, after a good overhead at least. I've never noticed anything in insite for this either?
It's under the Advanced ECM data, in the High Pressure Common Rail Injector Setup. When installing new injectors, you'll need to update the injector barcode (not trim). I couldn't remember what it was for sure as I didn't have my pc around at the time.
RE: A few issues - chaos2law - 08-22-2016
Ok, I'll take a look at that. Thank you
RE: A few issues - Rawze - 08-22-2016
(08-21-2016 )chaos2law Wrote: Thanks sir, I have insite and am aware.
I was kinda wondering about the injector trim mentioned above. I was under the impression that the injectors were plug and play, after a good overhead at least. I've never noticed anything in insite for this either?
On the newer common rail engines (CM2250/CM2350), there are indeed injector trims that need to be set when replacing an injector. On the older CM870, CM871 engines there is not.
When replacing an injector on one of the newer engines, write down what cylinder the injector is going to go into on the injector with a sharpie next to the trim code, then take pictures it to keep for reference.