Acceleration, or not so much...

[BobLabla]

(08-12-2017 )Hammerhead Wrote:  

(08-12-2017 )BobLabla Wrote:  Anyone have the nuts to do the overhead themselves?!? I think I may buy what I need to do it so I can stay on top of it once a year. But first I need to make sure the injectors are all doing what they are supposed to. I just hope I don't go through it all and have some kind of blockage in the fuel system.

Running an overhead is not hard to do, it's a great first procedure. If you don't already have a Quickserve.cummins.com account, go create one. Go into the service manual and print the procedure out, and follow it step by step. If you can tackle this, it will help give you the confidence to build your mechanical altitude and soon you'll be doing your own inframe...

Tools needed for the overhead once the rocker cover has been removed:
3/4" drive ratchet and a short extension-used to bar the motor over
A dial or split beam type torque wrench(small increments, value is 71in/lbs-8Nm) with an 8mm Allen socket-for adjusting injector preload on dual cam engines (570, 870, 871)
A torque wrench for the adjuster jam nuts(range of 15-50 ft/lbs)-multiple is nice so you don't have to change settings from injector to valve to jake every cylinder
A 6mm Allen wrench-for the valve adjuster
A 3mm Allen wrench-for the Jake adjuster
A 24mm socket for the injector jam nut
A 19mm crows foot-for the valve jam nuts
A 13mm crows foot-for the jake rocker
A 0.015" feeler-for the intake valve clearance
A 0.024" feeler-for the exhaust valve clearance
A 0.276" or 7mm feeler (or stack of feelers equal to)-for the jake rocker clearance
*A dial indicator and magnetic adjustable base to measure jake detent to valve pin clearance after adjustment

Your first time will take you the best part of the day...

*Another trick if you don't have a dial indicator and magnetic base; after the jake rocker is adjusted, rock it back towards the cam, place and hold a 0.030" feeler on top of the exhaust valve where you had the 0.276"/7mm feeler. Now rock the jake rocker into the detent position. Now push the jake rocker down towards the valve, if you still have slight clearance your head is good. If you have none, watch the jake rocker very closely while you slide the 0.030" feeler out flat, if it moves DOWN further into the detent, your clearance is at or beyond critical. This is how I do it when I don't have my dial indicator with me.

Very cool. Yeah, I was asking my mechanic and they charge some crazy 8 hours or so. F that! I'd feel better anyhow if I am finally responsible for it running correctly. I'm ordering all the tools, although I thought it was .014 and .027 but I'll check the Cummins site like ya say. I haven't seen anyone do the magnetic base and caliper test except for a Cummins made video on YouTube so that I need to look into a bit more. Thanks for the info tho and I hope to do a follow-up soon. Just hope nothing jumps out and bites me whaen I pull off the cover, as it's been quite a ruckus under there, and Jake's haven't worked for sh#* but maybe a tiny little bit when it's cooled down.

[Rawze]

(08-12-2017 )BobLabla Wrote:  ...
I was asking my mechanic and they charge some crazy 8 hours or so
...

eeehhh???? -- 8 HOURS!??? -- TO ADJUST THE OVERHEAD?? -- It takes about 20 minutes to adjust all the valves once the engine cover is off if you have done it a few times already. Engine cover and access to the front of the air compressor takes about 10 minutes to 20 minutes depending on truck model.

total, 40 - 60 minutes maybe for someone skilled at it, 2x longer for someone learning along the way.

[BobLabla]

(08-12-2017 )Rawze Wrote:  

(08-12-2017 )BobLabla Wrote:  ...
I was asking my mechanic and they charge some crazy 8 hours or so
...

eeehhh???? -- 8 HOURS!??? -- TO ADJUST THE OVERHEAD?? -- It takes about 20 minutes to adjust all the valves once the engine cover is off if you have done it a few times already. Engine cover and access to the front of the air compressor takes about 10 minutes to 20 minutes depending on truck model.

total, 40 - 60 minutes maybe for someone skilled at it, 2x longer for someone learning along the way.

I know Rawze, right!? That's exactly why I'm going to tackle it myself. Then I'll have the tools to do it once a year. Is it pretty easy to see and identify any possible damage to lobes when I'm in there?! Haven't seen it up close yet just in the vids. Just worried that it has never been done even though it was a big fleet, fleet truck....

[Waterloo]

Check the jake brake harness when you are in there, it is more than likely time to replace. The heat eventually destroys the harness. It comes in from the driver side center, through the side of the head. You will see it, if brittle or frayed, simply replace. And watch for the plastic clips that hold it in place, DO NOT break and drop one in the head, they can be a real bitch to get out.

[BobLabla]

(08-12-2017 )Waterloo Wrote:  Check the jake brake harness when you are in there, it is more than likely time to replace. The heat eventually destroys the harness. It comes in from the driver side center, through the side of the head. You will see it, if brittle or frayed, simply replace. And watch for the plastic clips that hold it in place, DO NOT break and drop one in the head, they can be a real bitch to get out.

Oh, you mean that s.o.b that's pissing oil out from just under the valve cover all over the driver's side of my once clean engine?! Yep, I'll be swapping that out too soon. I figured it wasn't a forever part considering the beating it must take on the head.

[Waterloo]

Well, pissing oil sounds more like your oil pressure sending unit or the cam shaft positioning sensor. I doubt it is your jake harness, but could be. If I were doing this, I would replace both the cam and oil pressure sending units. What did I pay, around $25 for the oil pressure unit and I think around $34 for the cam sensor. That oil pressure sending unit is the one that normally pukes oil and makes a real mess.

The oil pressure sending unit is in the driver side of the block behind the fuel filter. You have to remove the fuel filter to get to it. The cam sensor is up there right next to the Jake Harness, a bit of a bitch to get to, but not that bad.

[Waterloo]

The valve cover gasket is supposed to be reusable, but being the first time in, I would make sure you have access to a new one if need be. Just a thought, as they do wear out.

[Hammerhead]

(08-12-2017 )BobLabla Wrote:  Very cool. Yeah, I was asking my mechanic and they charge some crazy 8 hours or so. F that! I'd feel better anyhow if I am finally responsible for it running correctly. I'm ordering all the tools, although I thought it was .014 and .027 but I'll check the Cummins site like ya say. I haven't seen anyone do the magnetic base and caliper test except for a Cummins made video on YouTube so that I need to look into a bit more. Thanks for the info tho and I hope to do a follow-up soon. Just hope nothing jumps out and bites me whaen I pull off the cover, as it's been quite a ruckus under there, and Jake's haven't worked for sh#* but maybe a tiny little bit when it's cooled down.

You are correct sir!
I made a mistake when writing my post and you had the common sense to verify and not just believe some hack posting crap on the Internet, good job! I have corrected my post as I don't want to spread bad info.

Yes, Cummins states 0.014" & 0.027" for intake and exhaust clearances on any of the ISX's I've worked on.

In another thread Rawze stated that Mr Hagg has shown him where 0.015" on the intake improves oil flow at operating temperature, which is why I recommend this clearance, but that is for you to decide.

If your jakes are weak, it may also be that your Jake rockers need new check valves and springs. When you run your overhead, if the Jake rockers don't "snap into & sit sharply" on the detents it is a good indication that; the springs are weak, the check valves are worn, and the rocker shaft detent holes are worn. I recommend replacing the springs every (2) years. There is no science behind this recommendation, it is simply that the springs are dirt cheap and theoretically the stronger they are, the better the seat the Jake rocker has in the detent and the less wear the check valves (next cheapest part) and hopefully prolong the life of the rocker shaft (the most expensive component of them).

[Rawze]

(08-12-2017 )BobLabla Wrote:  Oh, you mean that s.o.b that's pissing oil out from just under the valve cover all over the driver's side of my once clean engine?! Yep, I'll be swapping that out too soon. I figured it wasn't a forever part considering the beating it must take on the head.

Engine brake harness leaking oil is a very common problem that happens when the crank case filter is not replaced often enough, or there is high levels of blow-by under engine load. If your engine brake harness is pissing oil, that is a sure sign of excess crank case pressure. That is bad for the engine and especially bad for the turbocharger!.

REPLACE OR DRILL OUT THE CRANK CASE FILTER!!! (most guys drill em out)...
maintenance-free one from cummins ... http://rawze.com/forums/showthread.php?t...50#pid8950
or to drill out the one you got ...
http://rawze.com/forums/showthread.php?t...376#pid376