Evenin, 2nd gen crowd...

On the 3rd gen CR trucks, we can measure the high pressure fuel with a rail pressure gauge. Is there a way to see what the VP is putting out? I'm not quite as edumicated on the VP's, hope you can shine a little light on it for me...

TIA...

mad

 

i am sure there is some special fancy tool that you could. buts its not like the common rails that always have 20k psi.

 

Check to see what the pop off pressure is on the injectors!

 

It could be done if you wanted to spend a few bucks, the rail on the common rail trucks sits at a certain pressure and varies a certain amount, the pressures change very slowly compared to the injection event from the VP or other injection pump and the sensors on a common rail are cheaper and have a slower response time, they are designed for more static type pressures.

To measure the pressure on an injection line on a VP or any other type of injection pump you would have to build special fixtures and attach special pressure transducer with an appropriately fast response time (more dynamic, usually won't work for constant or slow pressure changes) with a data collection system attached, an injection event is only fractions of a second.

This type of information was probably instrumented and gathered by the Bosch during the R+D phase of the pump/injector design.

Mark, Hope that explanation helps.

J-fox, the pop pressure is only the pressure when the injector (aka the valve) opens and allows fuel to spray into the cylinder, the peak pressure will be much higher than the pop pressure.

 

I can't imagine a gauge would last too long jumping from zero to 20,000+ psi and back several times a second.

 

A gauge no, a solid state pressure transducer would last almost indefinitely with proper care. Would be similar to the type used to measure the chamber pressure on a test barrel.

 

Six rail pressure gauges mounted in a rear-facing 'shaker' scoop(like an old Trans Am)....maybe not what you were looking for, but it would sure look Edit!

 

Mike, Awesome... thanks for the explanation. That's kinda what I was looking for.

How in the heck do you know when the VP is going out?

 

when it won't run any more

 

here is the best explanation as to when a VP goes out, or what to look for

http://www.bluechipdiesel.com/vp44diagnostichelp.html

 

That is a pretty good link!