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Discussion Starter #1
I went to the airport today and filled my '82 300SD up with Jet-A (Jet fuel). It was $2.95 instead of $3.60 for Diesel. I drove it 30 miles home and let it idle for an hour without a hiccup. It was bone dry when I filled it up, so I know it was burning the Jet fuel on the way home. The only difference I can tell is that it smells like a Citation is in my driveway! For the lack of lubricity of Jet-A compared to Diesel i put half a quart of SAE30 in the tank. Has anyone tried anything like this before?
 

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Discussion Starter #3
You might check the Jet-A prices at your airport. They set prices by the batch at this airport so they don't update their prices until they buy another tank. Right now it is considerably cheaper. I got the idea when I flew to Amarillo and there was a twin star airplane with two diesel motors and he was filling up with Jet-A.
 

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Yeah, and just to be on the safe side, make sure it's not dyed red, or a color obviously not normal for fuel.

This is how them revenuers find fuel tax cheating. You have a better chance of winning a $200 million lottery than being caught...unless you piss off the wrong person.
 

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I've done a little research about running jet-a instead of diesel. The jet-a is a lighter fraction than diesel and has additives to prevent gelling at cold temps. I'd feel more comfortable running it in my car if I could do a comparison of egt's of each. I've got a gut feeling that it might be running hotter than diesel. I remember while in the military we could select different fuel settings on the trucks if we were running mogas, diesel, or jp-4. I'd probably toss an additive containing a lubricant (sulphur) to protect the IP and injectors. Jet-A is not dyed to prevent confusion with aviation gasolines that are dyed either red. blue, or green to denote octane rating. Jet fuel is a natural straw color in volume and will eat a gasoline piston engine in a matter of a few seconds at high power settings.
 

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To add to what Azimuth said, Jet-A should be use-able at least for the short term. There are 2 main additives in Jet-A that diesel doesn't have, so I think it might be anyone's guess what effect those differences might have on the longevity of your fuel system. The main problem I see is that the EPA will fine you huge money if you are caught burning any sort of aerospace fuel in your road-going motor (be it Jet-A, AVGAS, etc). I'm surprised they sold it to you at all unless you had a legitimate looking service vehicle with tank. And yes, Jet A should never be any other color than "clear to straw"....otherwise you probably have something else mixed in
 

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Discussion Starter #7
I know Prist is an additive in Jet-A. It keeps the fuel from gelling in cold temps. Thats part of the reason I wanted it, it starts much faster in the morning. It's a much easier alternative to replacing my block heater. What is the other additive? and do you know where I can get a fuel treatment with a lubricant in it?
 

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I know Prist is an additive in Jet-A. It keeps the fuel from gelling in cold temps. Thats part of the reason I wanted it, it starts much faster in the morning. It's a much easier alternative to replacing my block heater. What is the other additive? and do you know where I can get a fuel treatment with a lubricant in it?
Actually PRIST is normally an add-on which is either pumped through an auxillary system on the fuel truck, or by hand by the line attendant....so its not technically going to be present unless you had a truck come over to your car and pump it in. Not sure how they do it with the heavies on the ramp of a major airport, but I assume they have some sort of a system to inject it there as well. Even w/ a "rogue" spout in place of the normal over-wing J-spout, I doubt you could actually fit the tip into your gas filler neck to pump directly into your car's tank. Either way I was actually speaking of 1) an anti-bacterial additive so you don't get bacterial contamination in your fuel system (major problem in certain environments), and 2) some sort of a special lubricant. I can't remember the chemical names of these additives, but thats what they do. PRIST is to my knowledge the civilian band-aid for not having the same anti-ice additive that JP-5 and JP-8 have. Probably too much information, but in a past life I worked as a line service attendant at an airport (the gas kid), so I have a weird interest in fuels.
 

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Prist is an anti-ice agent that prevents water from coming out of the fuel and forming ice crystals in the fuel system and causing a blockage. I try to keep my SD out of the flight levels but I do get to Vr on several occasions on my way to work :) I'd look at using on of the Power Service additives for additional lubrication to protect the injectors and the IP. One of them is also an anti-gel agent. Again, I'm a bit reluctant to try this without a TIT gauge to see what's going on. I can get jet fuel all day long but I don't want to be putting the hurt to my 299,650 mile old engine just yet. This would be a great project for someone to do some field test to compare the fuels. You might float this over to the W123 forum and see if anyone there has any experience or data.
 

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Actually PRIST is normally an add-on which is either pumped through an auxillary system on the fuel truck, or by hand by the line attendant....so its not technically going to be present unless you had a truck come over to your car and pump it in. Not sure how they do it with the heavies on the ramp of a major airport, but I assume they have some sort of a system to inject it there as well. Even w/ a "rogue" spout in place of the normal over-wing J-spout, I doubt you could actually fit the tip into your gas filler neck to pump directly into your car's tank. Either way I was actually speaking of 1) an anti-bacterial additive so you don't get bacterial contamination in your fuel system (major problem in certain environments), and 2) some sort of a special lubricant. I can't remember the chemical names of these additives, but thats what they do. PRIST is to my knowledge the civilian band-aid for not having the same anti-ice additive that JP-5 and JP-8 have. Probably too much information, but in a past life I worked as a line service attendant at an airport (the gas kid), so I have a weird interest in fuels.
We don't use Prist at the airlines! Our aircraft move so much fuel through them that's from surveyed sources that we don't sweat it. My aircraft has a fuel heating system once it's out of the tank so it's no issue with small amounts of water. I figure I did my fair share and burned 120,000 lbs in my little turboprop in Feb. I ain't going to do that again anytime soon!
 

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Discussion Starter #11
My 300SD has about 300,000 miles as well. I figured hell, it's been through 26 years of running all sorts of diesel, nothing can slow this thing down. What's worse, doing a Jet fuel experiment on a brand new diesel engine or a very old diesel engine? I drove it 223 miles round trip today. That's the rest of the Jet-A i put in it; about 300 miles total. I guess if I keep doing it I should come up with something better than a little motor oil to add for a lubricant.
 

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My 300SD has about 300,000 miles as well. I figured hell, it's been through 26 years of running all sorts of diesel, nothing can slow this thing down. What's worse, doing a Jet fuel experiment on a brand new diesel engine or a very old diesel engine? I drove it 223 miles round trip today. That's the rest of the Jet-A i put in it; about 300 miles total. I guess if I keep doing it I should come up with something better than a little motor oil to add for a lubricant.
Here's a link to the PS products: Power Service Products, diesel fuel additives, prevent gelling, clean injectors, disperse water, boost cetane, reduce emissions, improve fuel economy

Did you notice any difference in power or fuel mileage with the jet-a over #2 diesel?
 

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Discussion Starter #13
Thanks alot for the link. I average 24 mpg on the highway with no. 2 diesel. When I calculated my mileage yesterday it was about the same, no discernable difference I could tell. As far as power goes, there is no more power after the enigne is hot, but in the morning there is a difference. It was below freezing when i started her this morning and it was the first morning in a while i didn't have to crank it for awhile. It just cranked right over. Also, if I don't give it time to warm up after I crank it, it is extremely sluggish until it gets up to temp. Very little acceleration. But this morning, it seemed to respond much more quickly to acceleration.
 

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We don't use Prist at the airlines! Our aircraft move so much fuel through them that's from surveyed sources that we don't sweat it. My aircraft has a fuel heating system once it's out of the tank so it's no issue with small amounts of water. I figure I did my fair share and burned 120,000 lbs in my little turboprop in Feb. I ain't going to do that again anytime soon!
ahh...yeah, I suppose that makes sense. I'd say over 50% of the corporate traffic that came through our FBO passed on the PRIST as well, at least anything larger than a CJ1. Plus for widebody fuel loadouts, that would be a lot of damn prist haha.
 

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I have put plenty of gallons of JP8 through my VW golf 1.6NA diesel with no problems yet. I also added a bit of motor oil, or vegetable oil to it in an attempt to add some lubrication. I would say my fuel consumption is about the same after burning it for about 700 miles or so.

To my knowledge, and if anyone wants to chime in JP8 and Jet A and JetA1 are very close to the same thing.

To FLYNAVY:
My NATOPS says JP8 and JETA and JETA1 are close to the same thing.
 

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To FLYNAVY:
My NATOPS says JP8 and JETA and JETA1 are close to the same thing.
Sure thing....never said they weren't, just that JP8 has an anti-ice additive from the refinery, and Jet-A doesn't, hence the need in some cases for PRIST when using Jet-A

There IS a small difference between any sort of Jet fuel/Kerosene and Diesel fuel, but that very well might not matter anyways.

From my NATOPs:
Fuel Types and Specifications. When
commercial jet fuel is used and does not contain
anti-ice/fungicide (PFA55MB, MIL-I-27686, or equiv-alent),
it must be added during fueling per approved
method to assure proper anti-icing protection and
long-term fungus control. Fuels having the same NATO
code number are interchangeable. Jet fuels conforming
to ASTM D-1655 specification may be used when
MIL-T-5624 fuels are not available. This usually occurs
during cross-country flights when aircraft using NATO
F-40 (JP-4) are refueled with commercial ASTM Type
B fuels.
 

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As a side note, I used to run a 50/50 mix of 100LL avgas and regular no lead fuel in my 1962 MGA 1600 MkII. Also ocassionally in a '72 TR-6. Since 100 low lead avgas has more lead in it than the old premium grades of gas before the no lead now used, the old cars ran much better. The MG's engine was designed to run on leaded gas.
 

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As a side note, I used to run a 50/50 mix of 100LL avgas and regular no lead fuel in my 1962 MGA 1600 MkII. Also ocassionally in a '72 TR-6. Since 100 low lead avgas has more lead in it than the old premium grades of gas before the no lead now used, the old cars ran much better. The MG's engine was designed to run on leaded gas.
Just don't try to run AVGAS on a fuel injected vehicle with a catalytic converter. And as I said previously, you can be hit with a serious fine for running Av fuel in any car anywhere (even off-road). Like 10 times the value of your car....
 

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Just don't try to run AVGAS on a fuel injected vehicle with a catalytic converter. And as I said previously, you can be hit with a serious fine for running Av fuel in any car anywhere (even off-road). Like 10 times the value of your car....
Sorry to say I don't own either of them anymore. Run avgas in a modern car? Why the hell would anyone want to? Avgas is way more expensive than the premium our cars use.
 
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