Fuel pressure sensor install

[galaxie428]

I am installing some new gauges, EGT, boost and fuel pressure. I have found some info on here where others have installed the EGT and Boost but can't seem to find anything about the fuel pressure. Should this go before the small filter shown as 3 below or after the filter as shown in 1 or 2? If one or two, which is the better location? If there is another option, I would be happy to hear your suggestions.

 

[Suprman]

On top of the lift pump output line there is a pressure sensor that is only used with the ste ice diagnostics. You can swap your sensor for that one.

 

[galaxie428]

Thanks for the quick reply. I will use that location then. That should be easier than any of my bright ideas!

 

[sweetk30]

next question .

whats a good pressure to see ?

 

[74M35A2]

The Bosch injection pump has a pressure relief valve on the return outlet side of the pump, built within the banjo fitting that the return line is connected to (front of pump). I believe that is rated to open around 25psi, therefore keeping about 25psi on the system delivery pressure between the lift pump, through the block mounted spin on filter, and into the injection pump, on the 6CTA8.3. This line likely has a large amount of pulsations in it, with each stroke of the mechanical lift pump and corresponding opening of the overflow valve. Try to get a pressure gauge that has a snubber on it or reduced orifice opening to dampen this oscillation.

 

[WillWagner]

^^ This is correct. The lift pump is capable of upwards of 70 psi and it does can have serious pulsation. It is better to install the sensor/test fitting after the filter. This will tell you when you have a filter issue.

 

[74M35A2]

^^ This is correct. The lift pump is capable of upwards of 70 psi and it does can have serious pulsation. It is better to install the sensor/test fitting after the filter. This will tell you when you have a filter issue.

One could monitor spin on fuel filter blockage that way, and maybe the volume of the filter could act to dampen some pulsation, but it is hard metal piping from the filter to the injection pump, so more difficult of an install. But, aftermarket does make a banjo fitting for the injection pump inlet connection which has 1/8" pipe thread for a pressure gauge to easily do it this way though. People have also drilled out their stock inlet banjo fitting to accept an 1/8" pressure tap fitting. A lot of the common Bosh injection pump parts used on older diesel Dodge Rams (Cummins 5.9L with Bosch P7100 injection pump) fit the Bosch MW injection pump as well. There is a recent thread here about somebody changing their overflow valve to maybe an adjustable one if I remember correctly, in an attempt to slightly increase power, if the OP wants more info about expected system pressure and such.

Example link to aftermarket banjo fitting for Bosh injection pump fuel inlet pressure monitor port: http://www.dieselpowerproducts.com/p-12432-14mm-banjo-bolt-snubber-94-98-59l-12-valve-cummins.aspx this one is 14mm, there is also a 12mm one, so do your homework first (5.9L with VP44 pump).

Interesting read on stock Cummins lift pump, could be biased though: http://www.torkteknology.com/news/5/Technical-Article-Number-One%2d-The-Cummins-Lift-Pump.html

 

[WillWagner]

Made many of the fittings, not hard.