digital snap-on mt1480 luminosity meter

[jtate]

i put 8 new injectors in my truck and its changed the timing drasticly. i have a digital snap-on luminosity meter but am not to familiar with it. ive used it a couple times trying to set the timing but dont know if i timed it right. my problem is im trying to set the timing to 1.5* at 2000rpm, with a 20* offset but dont know if the meter is supposed to read -1.5 or +1.5 to be ATDC? if anybody has a meter like this please enlighten me on how to use this thing.

 

[tractorman86]

1.5 ATDC is -1.5 if you set the meter to 20* ofset, where did you get that number? most people are shooting for +8-8.5

 

[icanfixall]

I'm not familrar with the snapon tool but... I think the 3000 rpm is about 1000 rpm too high. Others will chime in and I'll be watching this closely. I have been thinking about that particular timing tool. I currantly have the Kent Moore Tach N time J33300.

 

[jtate]

1.5 ATDC is -1.5 if you set the meter to 20* ofset, where did you get that number? most people are shooting for +8-8.5

tractorman from my understanding 8.5* is using a pulse timing meter, remember mine is a luminosity probe it reads actual combustion in the cylender.

 

[jtate]

icanfixall im sorry i meant 2000rpms.

 

[jtate]

I'm not familrar with the snapon tool but... I think the 3000 rpm is about 1000 rpm too high. Others will chime in and I'll be watching this closely. I have been thinking about that particular timing tool. I currantly have the Kent Moore Tach N time J33300.

i purchased the meter off of fleebay for $250.00, it had everything that comes with the meter new. both luminosity probes were brand new never used and the only thing that was used was the meter and the pickup for timing a gasser. i just dont know about the -/+ reading on the meter to be ATDC. i had the timing set to +2.0 before the new injectors, and that was with the ip rotated towards the passenger side.

 

[MUDKICKR]

i was just talking to my snap on guy about that tool, i was thinking about buying it. he priced me a new one for 300 bucks. i think im going to buy it but i am going to get some instuctions first.

 

[jtate]

i was just talking to my snap on guy about that tool, i was thinking about buying it. he priced me a new one for 300 bucks. i think im going to buy it but i am going to get some instuctions first.

mudkickr mine has the instruction book that came with it but theres nothing in it about my issue. if your snap on guy can give you any info on it other than what i have i would be greatly appecative. i have asked this question several times and nobody has answered it yet.

 

[RLDSL]

i was just talking to my snap on guy about that tool, i was thinking about buying it. he priced me a new one for 300 bucks. i think im going to buy it but i am going to get some instuctions first.

Instead of spending $300, why don't you just get a Ferret for about $160 That critter combined with an advance type induction timing light and you're in business. THe thing is very easy to use and no having to fool with a luminosity probe, no magnet probe to wear down.

 

[sle2115]

You can also use a Ferret pulse generator (or MAC or Snap-on) with the MT1480. That's how I use it. I have the MAC pulse adapter.

 

[jtate]

You can also use a Ferret pulse generator (or MAC or Snap-on) with the MT1480. That's how I use it. I have the MAC pulse adapter.

yes ive looked at them for sale and plan on getting one someday. the meter you have, does it have the lumi probes? if so have you tried timing your engine using them and what is the meter supposed to read -1.5 or +1.5 to be ATDC?

 

[Diesel JD]

That 1.5*ATDC is supposed to be at 1400 RPM. Towcat would agree with you about making it closer to 2000 RPM and then be b/t 1-2*. I still can't tell you if you want +- 1.5, intuitively I'd say ATDC would be + but I may be wrongheaded in my thinking about this. Luminosity is a great method the only problem is that the probes can break and last I checked the were NLA from Snap-On. If you can get them they are about as much as a Ferret adapter. Luminosity compensates for differing Cetane values, for example the 1.5 figure is for 47+ Cetane, whereas you have to be closer to 3.5 for lower cetane rated fuels. If you don't adjust for cetane rating it can actually be less accurate than pulse timing, but if you have some clue as to cetane it will be the most accurate you can get.

 

[Agnem]

I use the MT1480, but strictly with the pulse method. The previous post is correct. 1400 is the required RPM for the luminosity method. Obtaining the cetane value is critical, which is why I don't use it.

 

[RLDSL]

I use the MT1480, but strictly with the pulse method. The previous post is correct. 1400 is the required RPM for the luminosity method. Obtaining the cetane value is critical, which is why I don't use it.

The chances of your local station having the actual cetane rating of the fuel they are selling are somewhere between slim and none. The cetane ratings posted are strictly minimum alowable cetane rating for the fuel that is being dispensed from that pump, it has no actual relationship to the true cetane rating of the fuel coming out of the pump other than the fact that the rating can not fall below that number

 

[jtate]

this brings me back to my original question ,,,,"with using the luminosity probe method is the meter suppose to read + 1.5 degrees or -1.5 degrees?" I have been asking this question for 8 months and nobody has gave me the answer yet .