How to set the timing on your 6.9 or 7.3 IDI and how to buy timing equipment.

Jesus Freak

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Hey, I gotta share this and I figure this is the thread to share on. So, on my FedEx route today I had a stop at probably the #2 diesel shop in my town, there's a bigger one I'll stop at at some point and ask the same thing, but for now, this is what happened today. After I delivered the package I asked about waste motor oil, but they had their tank pumped last week so nothing. But then I asked if they had the stuff to time a mechanically injected diesel like a IDI or 12v Cummins but specifically the 7.3 IDI, and he shop owner looked at me like an alien and said.........." All you do is line up the marks........" And I said "that's static timing, I mean dynamic timing".......alien look, maybe something on my forehead......."we just twist the pump a little if it seems like it ain't got power". I says "okay" and left. Crazy, just crazy. My hope was they may have a timing device that they would sell on the cheap because they didn't use it, it sounds like they don't know anything about mechanicing just computer programming. Do the new diesels basically control their own dynamic timing like a gas burner?
 

Oldred

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If you make it to northeastern North Carolina I can hook you up. I was only 1 deg off by ear when I checked with the proper tooling
 

Jesus Freak

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If you make it to northeastern North Carolina I can hook you up. I was only 1 deg off by ear when I checked with the proper tooling
I appreciate that, but for me it's more like, if you make it down here being your timing stuff.
 

Jesus Freak

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I got the last part of the timing package
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for these engines today. The timing light. And I have a large hard case to store it all in. I have an excellent wife! Besides. She wants to see this truck run again AND wants a ride.
Sweeeet!
 

dieseltech81

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So those of you who are smarter than I am, my experience is 20+ years of working on Detroit 2-smokes And Volkswagen and Audi diesels. I have owned a few GM 6.2 diesel trucks over the years and they have been great. I understand that anything under 200 hp is going to be a slug so I don’t expect them to do anything fast but they get the job done. Anyway picked up my first 7.3 IDI in a flatbed rollback tow truck. The engine was shot because apparently some idiot who thought they knew what they were doing touched every single nut and bolt on this truck including screws inside the injection pump where they had no business being. This has been a year long rebuild from bumper to bumper, so I completely rebuilt the engine (and most of the truck) it has .020 oversize pistons and rings, new cam and lifters completely rebuilt the cylinder heads, all new bearings. New injectors new injection lines and rebuilt injection pump. I own a machine shop so I did all the work myself and it turned out great. Only problem I’m having and maybe it is the tools that I’m using to time it. I bought the original Ford Road tundra tool but I am unable to use that because some moron used vice grips to take the original factory transducer off of number one injector and destroyed it. I have been unable to find that transducer in good shape so I bought an All-test Diesel timing tool That uses the luminosity probe in number one glow plug and the magnetic pick up on the crank The problem I had with that tool was anything above 17 or 1800 RPM it gave a very unreliable reading. I sanded down the crank harmonic balancer surface. cleaned everything as good as I could but still same results so I bought the Snap-on Lummy-mag 2. I tried some of the tools that use the timing light etc. but I quickly realize that those cheap ones do not have the 20° offset that I would need. Anyway I hook up the Snap-on to set my timing and Snap-on is showing a -2° at idle and -8.5 at 2000 RPM the manual for the Snap-on does not indicate what the negative means in front of the The timing reading. I was wondering if anybody else has used the Snap-on and can confirm that this is the correct reading. I pulled apart the timing covers last night just to make sure the lines and dots were properly lined up and they are! I Just don’t understand why it’s showing a negative Timing number, I also really had to rotate the pump over to the passenger side quite a bit from the original static timing marks. It seems to start an idle Very well. Nice and smooth. No smoke unless I give it a full throttle rev. Then it’s a touch of black. Certainly much cleaner than the day I bought the truck. It would cover 3 lanes of highway in thick black smoke. But I did not drive it after the rebuild yet. I did buy a new harmonic balancer thinking maybe the ring slipped on the outside of the rubber although it looks good. I am going to install that and re-check to make sure it’s OK. The distance between the two static timing lines on the pump flange is almost 1/8“ and my fussy German gut tells me that is probably not right. Thanks in advance, the amount of money I have invested in this truck. I want to make sure it lasts
 

ISPKI

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-20 degrees is 20 degrees AFTER top dead center.
Would an engine actually run at 8.5 after TDC?

My truck is sitting at 4.5BTDC and it idles pretty poorly, smokes just a bit, doesnt feel like it has the same getup and go like my other truck (could just be F-Super vs F250) and runs pretty hot. As far as I am aware, those could all be signs of the pump being out a bit. I cant imagine being at 8.5 after TDC would even be functional.
 

Ferdy Mint

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Our first IDI since coming back to the US in 2017 was a 1986 F250 430 cid atmo with 250 or 350k miles on it. The PO was a diesel heavy mechanic and he said he advanced it by several degrees. This guy was so big that his hands were like baseball mitts.

Once we got an electric fuel pump in it and good battery cables, that is the best starting IDI we have, and it gets up to 20mpg now that we put in a ZF5. Maybe advancing the timing helped. Can't be sure until we test it. But for now it ain't broken so I'm not fixing it.

Thanks for the timing tips. It's not as hard as I had heard.
 

Brian VT

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"Many with DTI units said they had to use a 5/16“ drill bit by hand to clean out the damper timing hole. (Use the top left hole.)"

I just did this and had to both run the drill bit a lot by hand (5/16" was loose in there) and also sand the probe (because the drill bit wasn't getting the job done by hand).
Anyway, this is the top right hole I'm messing with. The one closer to 12:00. The one closer to 9:00 is way too short to hold the probe.
Am I using the correct hole or is the instructions above correct and my engine is wrong?
 

ISPKI

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I use the top hole. Also had to clean it out with a 5/16" drill although mine just seemed to have alot of grime in there.
 

SkylabTech86IDI

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If you make it to northeastern North Carolina I can hook you up. I was only 1 deg off by ear when I checked with the proper tooling
Not sure if this is an open offer, but I’m comfortably about an hour north from Northeast Dragway if you and your timing kit are still available… once I get mine running ;)
 

hacked89

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This should help if you are interested in seeing the magnetic pickup before spending the money on the DTI light
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