Hello all,,,sometimes we get some leftover Jet A/JP8 fuel here at the shop...our mechanic uses it in his chevy duramax...but I am wary of using it in my HO 2500...although I have used it a couple times with a 50/50 blend (diesel/Jet A) because I was short on cash to by diesel...
anybody out there know of the pros/cons and effects of using JP8 in the Cummins? Thanks...

 

Main difference is that the lubrication properties of diesel are much better and as the fuel is sometimes used as lubricant for the high pressure fuel pump, running only on JET A fuel can ruin this pump if precautions are not taken.Pump=vp 44 If you are adding in 2 cycle oil like most of use in the forums,You should be fine,I see this at the airport alot to. JET A is a kerosene grade fuel, normally only available in the U.S.A. It has the same flash point as JET A1 but a higher freeze point maximum (-40°C). What year is the D-MAX?

 

I have ran Jet A straight and ran a lot of 50/50 also 2 stroke mix. IMO it doesn't have as much power and temps run 100 degrees higher in my truck. I used to get the fuel we defueled out of the helicopters and one time got a bunch of water and trash out of a barrel of fuel that got rained on. It was a mess had to drop the tank, change filter.Tore up my stock lift pump. What did I learn if your using sump fuel out of aircraft check for water.Hahahaa

 

The D-Max is a 2003-2004...I think...yes...sometimes, we defuel our helicopters and the fuel goes into a clean barrel...and it has a filter on it as well...we have been lucky not to have water or FOD in the fuel. As for lube, the mech will blend in some used aircraft oil, usually JetMobil, into the jet fuel...I have not run straight jet a but have used diesel blend and jet a/jetmobil blend...and have noticed a little less power...thanks for the input, just wanted to see what others say.

 

As far as runnin straight JP8 goes.... I'm in the military and all the duece and a halfs and Humvees and such run on straight JP8 in the desert. From talkin to a lot of the mechanics and bein broke down I can tell you this, it just doesn't have the necessary lubrication the fuel system needs. I've also been told it's been known to eat up gaskets and the like.

 

VP-44 pumps are VERY picky when it comes to fuel. You want to use at least 5% lube.

Theres some interesting info here: Diesel Fuel Characteristics and use