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FS voltage?

bison

bison

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Near Peace River-Alberta
anyone know if the FS(the sol on back of the IP) uses 12 v to operate ?.

I'm in the process of rebuilding a DS4 5521,i need to figure out wich way the FS works so i can establish a baseline to set the clearance.

I got my hands on a parts breakdown and test sheet for these pumps,but it dont exactly tell me the nitty gritty one needs to know.:nonod:
 
On the scope it looks like it operates between 1 and 5V depending on the RPM. Duty cycle AND voltage increases with RPMs, for anyone that really wants to know how it works. There are highs and lows peak to peak of 50-100V at the beginning and end of each 1-5V pulse.
 
You know whats even better, the scope pretty much shows the same voltage as my DMM in AC voltage mode.

The voltage increases with RPM/load and duty cycle. However on the scope the low also increases, but not at the same rate as the high pulse voltage. So as pulse voltage goes from 2-5V the base is at 1V and climbs to 2V. So the DMM showing 1.5V at idle and then up to 3-4V with increased RPM in park is showing the actual peak to peak correctly to ground and filtering out the spikes, ignoring the trough (1-2V) of the voltage draw of the retracted solenoid. As I suspected, since AC voltage does not just mean 60HZ commercial power, the DMM can adjust for the change in duty cycle (frequency) and AC voltage is peak to peak too.

Another myth busted :thumbsup:
 
Last edited:
Buddy,you got me completely lost here.
IMO That FS only opens or closes the spill valve,why would it need diff voltages to operate.
I aplied 12v to the sol to see wich way it moves(i hope i did'nt fry the thing in the process).It extends when energized, so it holds the spill valve closed when energized and retracts when de energized(for now all i wanted to know)

The 5 thou clearance must then be the amount the spill valve opens,prob enough to bleed off the pressure before the next cycle starts
 
So it operates on 5V, the voltage increases with RPMs may be coincidence in PMD output. However in order to control the extension and retraction very precisely and quickly requires more and more current. If the FS is a given resistance, then to get more current you need more voltage, using ohms laws.

And the other stuff is just to say you can determine if your PMD is operating OK with just a DMM, when its running in the vehicle. Doesnt mean PMD wont fail down the road, but if PMD is outputting the correct signal and truck wont start then you can assure that the PCM, sensors or PMD is not causing no start.
 
I see,
Now a dumb f""k like me can understand it:smile5:
i'm a mechanical man,these electronics give me still a major headache:mad2:
 
Are you taking lots of pics:rolleyes5: so you can do a BIG write up on rebulding ip's?:eek::thumbsup::D
 
Aply 12V the solenoid OPENS and the IP, Engine, etc. runs till you cut off the 12V.
This is the only way to shut off a diesel engine. The engine runs until there is now more fuel.

Cu,
Sven
 
Yeah, Bison is rebuilding it and messing with the FS (fuel solenoid) and not the FSS (Fuel Shutoff Solenoid) aka ESO solenoind (engine shutoff)

However, with our electronic injection the FS doesnt allow injection unless the PCM is sending the PMD an inject command and the PMD is telling the fuel solenoid to etend to allow pressure to the injectors. So the ignition acutally does control our diesel engine shutoff. The FSS/ESO is added safety, redundancy. Thats how you turn off a diesel with a mechanical injection pump though.
 
Hit a snag today on the rebuild on 2 fronts.
1) the IP 0 ring kit contains 2 shaft seals,only one happens to be the right size :pissed:, there's 2 seals needed on the shaft

2) i cant figure out where my 0 base line is suppose to be in order to set the FS clearance.:dunno:

It being easterbunny day, tomorow is a hollyday too,so I'm FF ed till tuesday to try to get a seal and try to pick a diesel shop mechanic's brain for specs.:drama:

I think i'm gonna get drunk givemebeer
 
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