Could Use Some Help Setting TDCO on OBD I

[Big T]

Alright I checked the stepper motor arm today and it moves up and down with acceleration. It also moved just after the engine started.

 

[JMJNet]

If it runs good and does not have any code, then leave it alone. IMO.

 

[dbrannon79]

ok, what I have learned using this software is that you have to click time set and leave it run for a few minutes. the desired timing will go to 0.0 but the actual IP timing should drop to around 3 to 3.5 if the IP is in the correct position. if it's lower or higher stop. loosen the IP and tweak it slightly one way or the other. then start again. the process gets very frustrating believe me! any slightest movement of the IP changes the degrees drastically!!

what I ended up doing after several attempts at this was leaving the lower two nuts holding the Ip loose and just snugging the top nut so it wouldn't move when running. but left it loose enough that I could slightly move the IP using a pair of channel locks on the body.

fired it up and clicked time set. had the laptop out next to me under the hood so I could watch it and while squeezing the channel locks with one hand and bumped them with the other till I was able to get it as close to 3.5 as I could. then tightened the top nut while it was still idling making sure that by tightening the nut the actual timing number didn't change. then I clicked off on the time set and clicked learn. this got me a -0.7 on the TDCO.

iirc if the actual timing is over 3.5 like 3.7 it will result a -1.xx TDCO and under 3.5 will do the opposite.
Although I could have that bass-ackwards

just be very careful with moving the IP while it's running. I have read in other places that this is not recommended. I don't know how much force it takes to spin the IP gear so leaving the top nut too loose might be an experience no one wants to witness!

I did this approach after being very frustrated going back and fourth with setting timing, off moving ip, setting time and so on... my theory approach is like how you time a 350 gasser tweaking the distributor while using the timing light approach.

 

[Big T]

OK I am back in Montana for the next week, hoping it stops raining to get the salmon flies up and flying and hitting the water for some fishing over the next week. All of which means we dropped working on this after observing the actuating stepper motor lever.

We've had a couple instances where the desired timing went to 0.0 and TDCO went to 0.0 while doing the time set. The actual timing was flipping around 5.0. Then we'd try the TDCO learn and in short order it would go to -2.46.

I have a bar drilled with two bolts in it to fit the IP, which allows us to move the IP. We've been doing this after work and after son has dinner with his family, so it was waning light conditions. Need to do it in the bright of day.

 

[Big T]

Here’s a video showing what’s going on with the time set and codes:

June 11, 2022

youtube.com

Here’s one instance where the desired timing was at 0.0, but actual at 8.0:



Have not been moving it with engine running as you’ve described, but yes on loose lower nuts while tightening/loosening the upper to move it.

 

[ak diesel driver]

Have you done the OS/CPS tests?

 

[Big T]

Have you done the OS/CPS tests?

No and please explain for my failing memory.

I was a recently installed new AC Delco CPS.

 

[ak diesel driver]

So to test the CPS you unplug the OS and then try to start it. It will take extended cranking for it to start and will start in limp mode but should idle smoothly and not have any hiccups. If it refuses to start or misses or anything out of the ordinary you either have a bad sensor or the wiring associated with it. To test the OS you just do the opposite , you unplug the CPS ........

 

[Big T]

So to test the CPS you unplug the OS and then try to start it. It will take extended cranking for it to start and will start in limp mode but should idle smoothly and not have any hiccups. If it refuses to start or misses or anything out of the ordinary you either have a bad sensor or the wiring associated with it. To test the OS you just do the opposite , you unplug the CPS ........

OS is the plug on top of the IP?

 

[NVW]

Yes

 

[MrMarty51]

I should have sent my home made copy of AK Dieseldrivers reversable ratcheting wrench along with that IP. Make it easier to loosen and tighten them IP bolts.
You want me to send it over ?

 

[Big T]

I should have sent my home made copy of AK Dieseldrivers reversable ratcheting wrench along with that IP. Make it easier to loosen and tighten them IP bolts.
You want me to send it over ?

We have a box wrench that was bent at an angle after heating it with a welding torch for this very purpose of dealing with IP nuts.

I am up in MT this week, driving down to SoCal next weekend where we’ll be for 3 weeks. I’ll get some time with the rig.

 

[jrsavoie]

I should have sent my home made copy of AK Dieseldrivers reversable ratcheting wrench along with that IP. Make it easier to loosen and tighten them IP bolts.
You want me to send it over ?

Do you have pictures of the wrench?
Is there a thread or post on AK's wrench?

 

[MrMarty51]

Do you have pictures of the wrench?
Is there a thread or post on AK's wrench?

I’ll get a pic of it. I think I had seen a pic of @ak diesel driver wrench and I think his is a little nicer than the one I created. It does work on all three bolts but the shape of tje handle is a little bit awkward, I just could not figure out a better way to make the bends.

 

[MrMarty51]

Do you have pictures of the wrench?
Is there a thread or post on AK's wrench?

The flex head flare nut wrench was suggested by one of the members in here for working on the injection pump fittings.
Then the ratcheting box end wrench, 15mm.

 

[ak diesel driver]

Hard Cold Start

Well didn't make any difference this morning. So I guess I'll try Bison's suggestion of clear tubing on the return line and see if I'm getting any air. I have a fuel pressure gauge on the t fitting and I noticed that the initial fuel pump prime only took it up to about 3 psi. I was actually...

www.thetruckstop.us

post 51

 

[MrMarty51]

Hard Cold Start

Well didn't make any difference this morning. So I guess I'll try Bison's suggestion of clear tubing on the return line and see if I'm getting any air. I have a fuel pressure gauge on the t fitting and I noticed that the initial fuel pump prime only took it up to about 3 psi. I was actually...

www.thetruckstop.us

post 51

Thank You Les.
That looks much more refined than the old wrench handles that I used.

 

[ak diesel driver]

If I had it to do over again, and I might, I use a ratchet wrench that has the switch to reverse directions.

 

[MrMarty51]

If I had it to do over again, and I might, I use a ratchet wrench that has the switch to reverse directions.

Oh yes. That is a must have item. I probably read that someplace to use a ratcheting end wrench with the reverse switch. Most times it would strain my brain to come up with such an idea.

 

[NVW]

If I had it to do over again, and I might, I use a ratchet wrench that has the switch to reverse directions.

It looks like it has the lever to switch direction?