Advancing pump timing

T

tinkertoy

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Putting the engine back together and i was looking at the old pistons. The spary pattern was out of the bowl a lot more than i remember, its been bout a year and a half seens i looked at them. The spary was out of the bowl about a three eights of a inch.
The pump is pined at 19 degrees and i got tape on the fluid damper. So i went 12 degrees on it. I first thought it was sit at 31 and then i got to thinking that it would be 25.
So is 25 where it was because the crank turns twice what the pump turns, or is it 31?
The thing was out of the bowl alot for 25.The pump has full cut valves and 093 lines with vp pop off on the injectors.
Like to get a timing lit to get it set this time. Whows close to me that has a lit?
 
How do you know it was at 25* when spraying out the bowl. Especially without a dial indicator.
 
Are you guessing timing by just by turning the crank? Like bsmith said you need to find out what pump you have and use a dial indicator on the #1 injection port. Or use a degree wheel on the crank. Mine is pinned at 24* with no issues on a 215 pump, 300 bar pop off, .020 DV's, .084 lines, and stock tubes. Also gotta remember to take into consideration that larger lines, tubes, DV's, and pop off pressure will change your timing intially set at the pump.
 
The pistons are SO and i dont really know what the injectors where. Going to send one off and have it pined. I was thinking they would be stock spray pattern. Or 155 ,what ever the injectors was made with 4-5 years ago.
I was not guessing at timing i said i had degree tap on the balancer with a pointer. It should have been 25 degrees i thought but iv been wrong before!
 
I think a dial indicator would be alot better but i dont have one. I thought if the pump was pined at 19 and go from there it would be close.Chevycummins have u had the head off ur to see what the pistons look like?
 
Mine was out of the bowl about as far when I was running 30*.

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the head hasnt been off in 230k miles i just looked through the injector hole while i had the injectors out getting reset. mine is an SO motor also but i have JL Machine 7x12 injectors which might have a different spray angle than yours also.
 
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With stock motor I was out of the Bowl at 30* so after replacing the head gasket I set it at 28* and its been great ever since.
 
Is there a thread anywhere with step by step instructions on changing timing. I've searched but all I can find is guys asking what timing to run with this size injector and what not. Any help would be great and sorry for the derail.
 
smokin24valve said:
Is there a thread anywhere with step by step instructions on changing timing. I've searched but all I can find is guys asking what timing to run with this size injector and what not. Any help would be great and sorry for the derail.
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Try goggle. Search for p7100 timing. Also it will depend on if you want to use a degree wheel, spill port, timing tool, or just guess.
 
If your using a legit timing tape on the dampner and the pump is pinned at 19*, you advanced it 12* then you are at 31*. The timing tape has done the thinking for you, you do not plan for 720* of engine rotation = 360* of pump rotation.
Timing tape with a fixed pointer and spill port method is my favorite. Ive also found true TDC with an dial indicator as well.


edit: If your sending out 1 injector, why not send all 6 and find out what size and spray angle you have and set them to p-pump pop pressures.
 
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