Setting timing by pulse method...

[The Warden]

Dumb question...

What should the injector pump be timed to when using the pulse method?

I ask because, unless my memory's bad, I've seen two numbers mentioned. In Mel's article, he says that the timing should be set at 8.5 degrees BTDC at 2000 RPM. But, when I talked with towcat on Thursday night, I recall him saying that I should set the pump at 7 degrees BTDC at 2000 RPM (I might be remembering what he said wrong, though).

So, is the "tolerance" that wide, or are there two different theories out there? Or, is there a difference between what a naturally aspirated and a turbo'ed engine should be set at? I've got an ATS 088 non-wastegated turbo and stock 6.9l fuel system parts (BB injectors) although the pump did get turned up a quarter turn's worth I eventually want to get Stage 1 injectors and a turbo calibrated pump from Ken, but I'll wait until the next time the IP dies. If the numbers are a choice between a bit more power and a bit better fuel economy, I'd rather stick with better economy...but first and foremost, the lower I can keep the EGT's, the better.

Thank you!

 

[OkieGringo]

Whatever method you use, it should be set at 8.5 BTDC @ 2000rpm. I don't think towcat would steer ya wrong, so pull yer head outta yer .- ... ... and chill with a beer. On second thought, towcat told ya to bring the beer, didn't he? Maybe ya'll already had tooooooo much beer and that's why ya can't remember . RichardCranium aka OkieGringo

 

[Agnem]

Dumb question...

What should the injector pump be timed to when using the pulse method?

I ask because, unless my memory's bad, I've seen two numbers mentioned. In Mel's article, he says that the timing should be set at 8.5 degrees BTDC at 2000 RPM. But, when I talked with towcat on Thursday night, I recall him saying that I should set the pump at 7 degrees BTDC at 2000 RPM (I might be remembering what he said wrong, though).

So, is the "tolerance" that wide, or are there two different theories out there? Or, is there a difference between what a naturally aspirated and a turbo'ed engine should be set at? I've got an ATS 088 non-wastegated turbo and stock 6.9l fuel system parts (BB injectors) although the pump did get turned up a quarter turn's worth I eventually want to get Stage 1 injectors and a turbo calibrated pump from Ken, but I'll wait until the next time the IP dies. If the numbers are a choice between a bit more power and a bit better fuel economy, I'd rather stick with better economy...but first and foremost, the lower I can keep the EGT's, the better.

Thank you!

The acceptable deviation is 2 degrees either way, so if your right on 7 or 8.5, your still good. However, 8.5 is what the book says. I don't know where Towcat got 7 from.

 

[The Warden]

The acceptable deviation is 2 degrees either way, so if your right on 7 or 8.5, your still good. However, 8.5 is what the book says. I don't know where Towcat got 7 from.

Mel, which book did you get the number from? I'm just curious, because I looked through my factory shop manual before posting this, and it only gave timing specs for the luminosity method.

I'm going to guess that I heard towcat wrong...I was rather preoccupied that night (worried about the glow plugs, plus finding out that there was a death in the family)... For the record, the beer was only for towcat I actually had to ask him what he meant by "fully leaded"...and I've never let a drop of alcohol touch my lips in my life. I have enough fun watching the drunks around me when I'm sober

 

[OkieGringo]

Mel, which book did you get the number from? I'm just curious, because I looked through my factory shop manual before posting this, and it only gave timing specs for the luminosity method.

I'm going to guess that I heard towcat wrong...I was rather preoccupied that night (worried about the glow plugs, plus finding out that there was a death in the family)... For the record, the beer was only for towcat I actually had to ask him what he meant by "fully leaded"...and I've never let a drop of alcohol touch my lips in my life. I have enough fun watching the drunks around me when I'm sober

We use to go to the local boat ramp and drink beer and watch the yuppies try to launch their new boats and end up launching their new SUVs. Really hilarious . OkieGringo

 

[Agnem]

Warden, You probably will never see a BTDC number for the 6.9 in a manual. Only the 7.3, because the 6.9 doesn't have a pulse timing adapter on the #1 injector, and the official factory method IS the luminosity method. However, if you time a 7.3 using the pulse method, and then check the timing with the luminosity method, you will find that the 6.9 figures apply to the 7.3 as well, so you can cross time a 6.9 using the 7.3 pulse method standard.

 

[The Warden]

Ah, okay...cool. Thank you!

I think I get to set it to 8, though...I played around with it a little bit today (before it started raining ), and turns out the timing light I'm borrowing only goes in 1 degree increments. Ehh, I imagine 0.5 degrees won't make too big of a difference I hope there's enough of a break in the weather tomorrow that I can get the timing done and the glow plugs finished, since it looks at this point like my truck gets to go to Santa Clara for the brakes...and I want to get everything else done beforehand...

 

[OkieGringo]

Do you know the way to San Jose/Santa Clara? Don't forget to bring the beer. Say hi to towcat for me. OG

 

[Michael Fowler]

We use to go to the local boat ramp and drink beer and watch the yuppies try to launch their new boats and end up launching their new SUVs. Really hilarious . OkieGringo

Its also fun watching them TRY to get those same boats back onto the trailers.

 

[OkieGringo]

Its also fun watching them TRY to get those same boats back onto the trailers.

one of those days a guy backed the trailer too far in and it dropped off the edge of the ramp. He paid us to dive down and attach a rope to the end of trailer then attach the other end of rope to his boat to pull the trailer back up. He was off his ass, and we were approaching quickly . There was quite a big audience .

 

[CaseyJones]

Warden, You probably will never see a BTDC number for the 6.9 in a manual. Only the 7.3, because the 6.9 doesn't have a pulse timing adapter on the #1 injector, and the official factory method IS the luminosity method. However, if you time a 7.3 using the pulse method, and then check the timing with the luminosity method, you will find that the 6.9 figures apply to the 7.3 as well, so you can cross time a 6.9 using the 7.3 pulse method standard.

Can I deduct that I can time my 89 7.3 w/a conventional timing light? My book doesnt cover timing this way (or IP/injector specifics)

If it can be done w/a timing light can someone lay down the basic proceedure (how diff. from gasser)

My chilton obviously is lacking in some important areas not outside my scope of learning/understanding. What book might I look for to prevent me from formulating stupid posts such as this one

Thnx

 

[Agnem]

I myself do not use a timing light, but with an adapter it can be done. There was a recent post by member Huff, that covered this topic.

 

[Magoo]

Warden, You got alot of irons in the fire. For what its worth, I set my timing by ear recently. Not sure what the actual was but the marks were lined up. So I set it by ear cuz my snap on light broke. Sounded ok with just a slight rattle. Checked it with my new light and was at 10 deg. Mileage did not improve over the 10 i was getting with the marks lined up. So I reset to 8 and am now getting 12. The slight rattle is gone. So 2 degrees seems to make a diff. Just my 2 cents.

 

[The Warden]

I just checked the timing...with the meter set to 8 degrees advanced (assuming I did it right) and the RPM's brought up to 2000, the harmonic balancer lined up perfectly...without even loosening one IP nut. Either I'm amazingly lucky or my ear's better than I thought it was...next tiem I se towcat and he has time, I want to re-check it with him there, to make certain that I'm doing everything correctly...this is almost too good to be true...

Thanks again

 

[The Warden]

Warden, You got alot of irons in the fire.

That I do and this wasn't even deliberate. I've been meaning to check the injection timing for over 6 months, but last semester at school almost killed me, so I didn't have time...and I decided that I WOULD do it as part of this project (namely, the glow plugs and battery cables).

Of course, the glow plugs were supposed to be FAR more straightforward than it was (I'm still ironing things out; think I have to try a factory wiring harness instead of my custom job that I spent $100 on ), and the brake issue popped up out of the blue (that one, I blame on karma ). The battery cables actually went surprisingly well...

Part of this is that I have the luxury of being able to park my truck and work on it without the fear of it being towed. In about 4 months, that luxury's going to go away, so I NEED the truck to be up to 100% by then. I have a lot more left to do...