how do you check timing in 12v

 

The most accurate is flow timing. It uses a timing light to strobe the mark on the balancer and a flow sensor clipped on the #1 injector line.

 

Where do you get a flow sensor for an injector line?

 

I cannot find the link.
A nifty kit has a flow sensor that clips on an injector line and has a timing light that strobes the balancer mark. A digital read out gives you the timing.

The Snap-on or Miller kit is accurate for setting the timing based on plunger lift, but the flow timing is more acurate for dynamic testing.

 

Interesting - I though everyone used the plunger lift method.

 

I used one of those at SAIT when I was in 2nd or 3rd year. its a diesel pulse adapter wired into pretty much a standard timing light. I don't recall the brand I used at SAIT but pretty sure snap-on or bluepoint has one.


Fueling around.......you realize that the 12v cummins has no timing advance feature whatsoever right? whether VE rotary or P7100. doesn't matter, theres no advance mechanism.

B series are set to operate at static base timing, thats as good as it gets.

 

I thought the VE's had a timing advance mechanism in them? The 215 pumps retard timing based on rack travel. Thats why they have the v-notch plungers, while the other pumps are all flat tops.

 

How much do they cost?

 

Last I looked at the timing set it was around $800
I'm still trying to find the link to the one used on my truck.

I say dynamic as plunger lift is a mechanical estimate of the pump based on an injector pop-off.

BTW, if you measure at the pump versus the injector with the pizeo clip, the delta is around 4° less at the injector.

VE pumps have over 16° of mechanical advance. Some of the Roosa pumps had an advance, too.

The lowly P pump has some funny stuff with the plungers as Tate noted. Actually as the rack travels it will advance the injection slightly. A full plunger pops off the injector a couple degrees sooner than an empty plunger.

 

School is in... - good info.

 

how does the VE dynamic advance work? How does it advance BOI with engine speed? What 6B uses a Roosamaster pump? I know some industrial 6Bs use a Nippondenzo, but thats all I've heard of.

I only knew about stanadynes with dynamic timing advance. i used that kit on an International years ago.

 

if it doesn't advance beginning of injection, its not a dynamic timing advance. I'm not sure what the purpose of that notch is. maybe increase fill time.

 

The purpose was to retard timing for emissions reasons. At full rack travel, you would lose between 4 and 6 degrees.

 

I was just comparing the VE to the Stanadyne Roose pump as they are very similar in internal design.
Never seen a Cummins with a roosa. That would be the 6.2/6.5 Chevy; 6.9/7.3 Internationals as well as John Deere.

 

I know for sure stanadyne on the 6.2 chevy has it, and I know its a weak design. but does the VE? I'm not convinced.

theres a couple former injection pump specialists at work I'll ask.