Trying out my DTI timing unit

[Brian VT]

I've got the probe in the tube, the transducer just above #1 injector, a separate battery for the DTI, and I powered the unit up.
I have the trigger switch on Low. I checked the offset and it says 20.0 Then I turned that switch to Probe and it reads 0.
I fired up the engine and RPM seems to be reading well and steady.
I plugged in the probe and waited until the degrees stopped flashing. It says -20.0 at idle (@700rpm)
I brought the engine revs up. The RPM reading is erratic at higher RPMs but I tried holding it close to 2k.
The degrees is all crazy. It's all over between 60-110.
I know the probes are finicky but is that what's causing these crazy readings? When I was holding the RPMs between 1500 and 2500 the degrees were never close to being down near 10, never mind the 9-9.5 that I'm looking for. It was usually close to 100.
What now?

 

[chicken bones]

There are many posts on this , if it reads - 20 it not postioned correctly . These things are very finicky I would suggest purchasing there timing light for this unit. I gave up on my probe had the same problems you are having. The timing light works . Good luck.

 

[Brian VT]

I'm stubborn and I've already spent a bunch of $ on this truck.
Many here seem to have been able to get the job done with the probe.
If the probe is causing what I'm describing then I'll mess with that. I have more time than $.
I would just like to know if that's where my problem is before messing with it.
Unless someone wants to lend me their light.

 

[Jesus Freak]

. I have more time than $.

Ain't that the truth! After you get it all figured out, take a vacation in majestic NW Florida and bring your timing equipment with you.

 

[Old Goat]

Here is a good write up by Big Bart on timing these engines.
Miss that guy, he was a wealth on knowledge.

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

This thread is how to set timing on your NA or Turbo 6.9 or 7.3 F250 or F350 pick up. When should you check your timing? Every 30,000 miles. As your pump and injectors wear, they begin to open sooner generally. (Lower pop pressure.) This changes your engines timing. As an IP wears it may take...

www.oilburners.net

Brian, at the bottom of each thread there are similar threads listed on the topic being discussed.



Goat

 

[Brian VT]

I've gone back through all? of them.
It seems like I am doing everything correctly but I'm getting timing readings (60-110) like no one else has experienced or mentioned. I guess that means that at least my probe is working and sending something.
So I guess it could only be the probe location or damper condition but I was hoping to hear from someone that has seen readings like mine and what they did to fix it.

 

[Brian VT]

Ok.
I messed with the probe and damper some more.
I've finally got it where the RPMs and degrees aren't jumping all over.
At idle (700 rpm) degrees read a steady 14. At 2000 rpm degrees read a steady 12.
Does this sound like I've got it working correctly?
Would the 12 explain the engine sounding "clacky" and rolling coal very easily?

I guess I need to turn my pump towards the driver's side?
I've heard to move it "the thickness of a dime". About how many degrees is each dime? Maybe 3 dimes would get me close to 9?

 

[kbenz]

These things are very finicky I would suggest purchasing there timing light for this unit.

I'm thinking on getting one of these. What timing light?

 

[Jesus Freak]

I'm thinking on getting one of these. What timing light?

Sure nuff, there's a timing light attachment. When you get one and have it figured out, feel free to take a vacation to majestic NW Florida and bring it with you. I got a 300 gallon tank of oil that I can top you off with!

 

[IDIBRONCO]

Would the 12 explain the engine sounding "clacky" and rolling coal very easily?

Yes. Mine was set more than 12* and, while I can't say that it would roll coal, it would put black smoke out of the exhaust fairly easily.

I've heard to move it "the thickness of a dime". About how many degrees is each dime? Maybe 3 dimes would get me close to 9?

I've seen someone give a guess at the number of degrees per dime thickness but I can't remember what it was. I think that each pump will vary some on the degrees per dime thickness. I would try only one instead of three. The pumps are pretty sensitive to how far they're turned.

What timing light?

DTI sells a timing light for these meters. You can also use an adjustable one for a gas engine too. Even though it costs more, I went with the one from DTI for ease of use (to me). I like the fact that you can run the trigger and the advance/retard buttons with one hand.

 

[Brian VT]

Thanks Bronco.

 

[Jesus Freak]

I've seen someone give a guess at the number of degrees per dime thickness but I can't remember what it was. I think that each pump will vary some on the degrees per dime thickness. I would try only one instead of three. The pumps are pretty sensitive to how far they're turned.

It really is "dynamic timing", there's so many factors : individual injectors popping, wear of the IP, fuel viscosity, etc. It ain't like timing a 302 for sure.

And the "dime thickness" is curious language to me, no one ever mentions quarters or nickels. And before there was electronic ignition in distributors think of how we splerged by sliding a whole dollar bill between the points..........if anyone can remember what "points" are.

 

[IDIBRONCO]

And before there was electronic ignition in distributors think of how we splerged by sliding a whole dollar bill between the points.

I was always told the top of a matchbook. I can remember points and matchbooks being given away free practically everywhere. In fact, if I dug hard enough, I may still have a points distributor or two for a 302 laying buried somewhere.

 

[Brian VT]

One more thing...does 14* at 700 rpm and 12* at 2000 rpm sound like my meter is set up/working properly?

 

[Brian VT]

I still have 2 dirtbikes that have points. And they would be one of the last things I'd sell if I fell on hard times.