My Pete rebuild

[Rawze]

(05-27-2019 )Nostalgic Wrote:  Ok, now, as I stated, everything was off when I replaced the rear timing actuator and installed the other 3 cleaned and inspected actuators and found the rear bank dead.

It was started twice (so I could get the camera and check my exhaust manifold) before I unplugged/plugged the rear timing actuator to stop the ticking.

Would the resistance of the new actuator cause this issue, or is it in fact bad? In other words, it it worth it to reflash the ECM and try the reman actuator again?


As it sits now-

I put the original timing actuator back on and it starts and idles fine. Since I had a new timing AND metering actuator, I replaced the rear metering actuator, and then used the plunger out of the old one to replace the worn/with a step plunger in the old rear timing actuator.

It still has .005" side play, but no step on the shaft.

unless you have been plugging and unplugging them many times., a person can usually just do several cut-out tests with the cylinders. This typically clears it up (and gives an indication if an actuator is actually bad / something is wrong)

Otherwise, how would you know if that sound your hearing is normal for a good actuator or not?

I can say this...

YOU MAY OR MAY NOT HAVE A BAD ACTUATOR ON YOUR HANDS THERE,.. I AM NOT THERE TO KNOW FOR SURE,.. AND YOU ARE NOT ME. -- BUT GENERALLY ...

there's no way in hell I would change out an actuator because of some stupid subtle 'clicking/ticking' sounds, slightly rough idle, or any other minor bullS#it. ... it would have to be pretty significant + stumble a lot and/or have a significant drop in fuel mileage or power, something CLEARLY MEASURABLE AND SIGNIFICANT .. for me to start justifying replacing a $500+ actuator. -- My own engine has 1.4 million and still 100% the original IFSM components/actuators that came from the factory. -- ,.. I STILL GET 9+ MPG!.

The IRONY is that it used to run rough at idle,.. when I REPLACE THE WHOLE HEAD it smoothed out -- way out. - Only thing I can contribute this to is significantly less wear in the cam bearings, as I re-used every bit of what came out/off of the old head including injectors, cams, rockers, etc. -- I later replaced my injectors because I knew they were slightly leaky and very old,.. but it had already been running a whole lot smoother at that point.

Its a big clunky diesel engine .. Do all the proper checks,.. ensure the valves are adjusted properly, do an injector leak down, do cut-out tests, check for excess wear on the shanks of actuators if paranoid about them worn out if you like,...

There ARE ACTUALLY WAYS to see if you have actual idle/fuel supply issues ... use CT to graph the mg/stroke the engine is using at idle,.. see if it is fluctuating up and down in a wavy sine-wavy type pattern by several mg/stroke,. or see if it is fairly steady / random by only a couple few mg/stroke.
--> Mostly steady = not typically actuator problems. -- measurably wavy = something is wrong like air in the fuel, worn out actuator, leaky injector,.. etc.etc.etc.

Also if it is using more fuel than normal, (or significantly less fuel than normal) that is an indication of actuator problems, injection timing issues, or higher than normal exhaust/turbo back-pressure.

I have seen guys who's engines report 0 - 8 mg/stroke on a graph,.. clearly there is a leaky metering or timing actuator. I have seen engines rev up and the mg/stroke go to zero, clearly a bad, hanging actuator getting stuck open. I have seen engines that use 50+ mg/stroke that have bad timing actuators, but I have also seen this when the turbo spooled up too much or something else in the exhaust is is bad/restrictive.

A person can also test the timing actuators (roughly) for correctness by overriding bypassing the start of injection with CT and moving the final timing form 0 to 5 to 6 to 7 to 8 to 9 BTDC. If the timing actuators are working properly, the sound of valve lash will get significantly louder at about the 7.5 BTDC or so SOI override setting (cm870/871 engines models only). This is also where the fueling at idle will break over and start dropping mg/stroke up to and all the way to about 9.0 BTDC where it reaches the extremes of what the engine can handle safely at idle without excess wear. Jumping back and fourth between 6.0 and 8.0 it should sound significantly different. If there is no sound change, either you need better hearing,.. or you have timing actuator issues that can be measured. there will also be a measurable change in how much fueling it uses (mg/stroke) at idle between these 2 points. All piston driven engines have this 'break-over' point in injection timing settings, where the sound changes significantly . It can be used to see if the engine ECM/computer's injection timing settings match this mechanical point.


Starting to get the picture???

ONLY IF THERE ARE SIGNIFICANTLY MEASURABLE AND ACTUAL SIGNIFICANT PERFORMANCE-CHANGING PROBLEMS would I do something about actuators, not some subtle BS or sounds, or stupid random idle variances that are too close to be measured...

If it passes all those tests / checks ... by-god RUN THE DAMN THING AND MAKE MONEY OTHERWISE instead of chasing ghosts, slightly rough idle, and any sort of stupid subtle BS that has nothing to do with going down the road.

I see a lot of people chasing that ghost of perfect, smooth idle and perfect smooth, rattle-free stuff for it to only drive them mad and waste all sorts of money endlessly eventually only to realize there is nothing actually wrong.

"Does the captain of his ship not know every screw and bolt and weld? -- When he is at sea and in battle long enough,.. he eventually will !" -- Thomas Kennamer