(Hollywood Physics) Does Jet Fuel Explode?

HomeBuiltAirplanes.com

Help Support HomeBuiltAirplanes.com:

BJC

Well-Known Member
HBA Supporter
Joined
Oct 7, 2013
Messages
11,233
Location
97FL, Florida, USA
I have no idea how much actual difference there is between Jet A and diesel fuel, nor how long it would take to damage an engine. You couldn't run it in anything that has to have an inspection, since it won't pass due to the higher Jet A sulfer content. I do know diesel has lubricity additives that Jet A does not, plus Jet A has things like anti-microbial additives and anti-icing additives that probably do nothing for your diesel engine. Diesel is also slightly heavier than Jet A, although I don't know the exact differences and, it has a few more BTU's per gallon. Rik, if you ran your Rabbit on Jet A that long I'd say you were probably lucky... or the thing leaked enough engine oil into the fuel to keep it going. Rabbits leaked everything into everything else! I drove my buddies Rabbit (no Jet A in this one) from Tucson to Las Vegas and literally had it floored the entire time, just trying to keep up with the heavier trucks - but not succeeding very well! We got there, which is what counts. If nothing else the thing kept running and running!
Cheers,
crkckr
I put over 200,000 miles on my diesel Rabbit. Never had any leaks. Only corrective engine maintenance was to replace a glow plug. Added gasoline, about 20 to 25 % to the fuel during cold weather (20F and below). It would get to 75 MPH on the Interstate with no headwind, and still get 55 MPG.

Burned lots of Jet A in small industrial boilers in lieu of No. 2 Fuel Oil circa 1982. It was cheaper because the fuel terminal operator had a take-or-pay contract and the airlines were in a slump.


BJC
 

Rik-

Well-Known Member
Joined
Sep 13, 2019
Messages
378
Location
San Rafael, California
Never mind, just thought you might want to know there are people on this site that help build the car you drove. But I was wrong, you will now go on the totally ignore list, not many on this list on this site, a lot of nice people.
Sorry, but from the comment I didn’t know what you were trying to say as in this comment you clarified it.

No problem it just wasn’t paraphrased correctly to make it understood is all.
 

Pops

Well-Known Member
Log Member
Joined
Jan 1, 2013
Messages
8,139
Location
USA.
I put over 200,000 miles on my diesel Rabbit. Never had any leaks. Only corrective engine maintenance was to replace a glow plug. Added gasoline, about 20 to 25 % to the fuel during cold weather (20F and below). It would get to 75 MPH on the Interstate with no headwind, and still get 55 MPG.

Burned lots of Jet A in small industrial boilers in lieu of No. 2 Fuel Oil circa 1982. It was cheaper because the fuel terminal operator had a take-or-pay contract and the airlines were in a slump.


BJC
My son put over 300,000 miles on a 1981 Rabbit and it still looked new. He still waxed the painted metal under the hood. Working for VW at the time I could buy 6 month old company cars for about 1/2 price. The VW gas had nice power but the diesel was low on power but high on mileage. We also made parts for the little rabbit truck. I would like the have a diesel Rabbit truck that was like new.
 

Rik-

Well-Known Member
Joined
Sep 13, 2019
Messages
378
Location
San Rafael, California
My son put over 300,000 miles on a 1981 Rabbit and it still looked new. He still waxed the painted metal under the hood. Working for VW at the time I could buy 6 month old company cars for about 1/2 price. The VW gas had nice power but the diesel was low on power but high on mileage. We also made parts for the little rabbit truck. I would like the have a diesel Rabbit truck that was like new.
My only problem with the car was the glow plugs went out at a little over 100K miles. I paid $400.00 for it and put new tires on it. Drove it to San Francisco for 2 years and parked it, climbed out the sun roof and found it where I left it every time.

Think I was getting in the 30's mpg range but I was beating it like a dirty towel the whole time.
 

Pops

Well-Known Member
Log Member
Joined
Jan 1, 2013
Messages
8,139
Location
USA.
The Rabbit was the first very high MPG full size car if memory serves. It was all the rage the first time gas prices went nuts.
Was bad about rusting until 1981. First year using the galvanized coated steel. VW of Germany said the American built Rabbit was a better built Rabbit than the German built Rabbit because of the better steel used.
Local man found a diesel Rabbit on Ebay this last year that was very nice, paid a huge price for it. More than it cost new.

Always wondered what happen the the 100 aluminum bodies that were stamped out. I didn't have anything to do with it, but I did check out the aluminum alloy and knew they were going to have problems with the hard aluminum in the draw press. They did, and had splits everywhere until getting the correct aluminum for the job.
 
Last edited:

Aerowerx

Well-Known Member
Joined
Dec 1, 2011
Messages
5,568
Location
Marion, Ohio
I put over 200,000 miles on my diesel Rabbit. Never had any leaks. Only corrective engine maintenance was to replace a glow plug. Added gasoline, about 20 to 25 % to the fuel during cold weather (20F and below). It would get to 75 MPH on the Interstate with no headwind, and still get 55 MPG.

Burned lots of Jet A in small industrial boilers in lieu of No. 2 Fuel Oil circa 1982. It was cheaper because the fuel terminal operator had a take-or-pay contract and the airlines were in a slump.


BJC
Forget what model year (1986 or 1987??) it was, but I used to have a 5-speed turbocharged diesel Jetta. I got 55mpg on the highway. 40 in city driving. And it had a 20 gallon tank. I could have gone 1000 miles between fill ups, but the most I ever did was 800.

It was all mechanical injection, and the last model year before they went to electronic injectors whenever that was. Got it at a good price, I remember, as it was the last one they had in stock after the new model year came out.

Hated to get rid of it, but was having knee problems. The clutch spring was the stiffest I had ever seen. (Besides, got married and the Mrs. couldn't drive a stick shift.:()
 

BJC

Well-Known Member
HBA Supporter
Joined
Oct 7, 2013
Messages
11,233
Location
97FL, Florida, USA
The VW gas had nice power but the diesel was low on power but high on mileage.
Shift to first gear, immediately switch the AC off, accelerate through the gears (with lots of patience), then switch AC on. It made a difference.


BJC
 

PMD

Well-Known Member
Joined
Apr 11, 2015
Messages
242
Location
Martensville SK
OT: diesel will both burn and explode, but not likely at atmospheric pressure. When diesel fuel is injected into the combustion chamber, if everything is right, it burns. BUT: if you remember the clatter and knock of old diesels, sometimes the charge would explode resulting in a big knock that would blow the water off of the cylinder liner on the cooling side and result in bad cavitation damage when the resulting bubble imploded. This "knocking" is why old tech diesels were so heavy - they had to tolerate the explosions that went with poor timing, chamber airflow/turbulence and bad atomisation of low pressure injection. I guess it MIGHT explode at lower pressures, but you would need a hell of a pile of energy to cause that to happen. It all depends upon what you call/define "explosion" (usually supersonic travel of flame front).

Off Topic: being an ex VW guy I would KILL to find one of those aluminum Rabbit (US Golf) bodies. Would make a dandy solo racer/sleeper. I will take great exception over the statement that the US made cars were in any way "better" than the German production ones. Our dealer council (Canada) REFUSED to accept the Westmoreland cars until 1981, even then over great protest. That plant and the products from it were a QA/QC disaster, even if they did rust less! But, I would grab an aluminum one in an instant.
 

Pops

Well-Known Member
Log Member
Joined
Jan 1, 2013
Messages
8,139
Location
USA.
OT: diesel will both burn and explode, but not likely at atmospheric pressure. When diesel fuel is injected into the combustion chamber, if everything is right, it burns. BUT: if you remember the clatter and knock of old diesels, sometimes the charge would explode resulting in a big knock that would blow the water off of the cylinder liner on the cooling side and result in bad cavitation damage when the resulting bubble imploded. This "knocking" is why old tech diesels were so heavy - they had to tolerate the explosions that went with poor timing, chamber airflow/turbulence and bad atomisation of low pressure injection. I guess it MIGHT explode at lower pressures, but you would need a hell of a pile of energy to cause that to happen. It all depends upon what you call/define "explosion" (usually supersonic travel of flame front).

Off Topic: being an ex VW guy I would KILL to find one of those aluminum Rabbit (US Golf) bodies. Would make a dandy solo racer/sleeper. I will take great exception over the statement that the US made cars were in any way "better" than the German production ones. Our dealer council (Canada) REFUSED to accept the Westmoreland cars until 1981, even then over great protest. That plant and the products from it were a QA/QC disaster, even if they did rust less! But, I would grab an aluminum one in an instant.
Yes, they had a OC problem at the stamping plant were I worked. We supplied all the panels for Westmoreland and also did stamping for Ford, GM and Dodge. Until the new computer measuring equipment was installed in the QC department there was a problem. I installed the equipment. Equipment made in Germany and all instructions and prints were in German. Had a factory rep from Germany that came with the equipment and could speak very little English. I got the help of one of the Tool and Die machinist that was from Germany. Was drafted in the German army when he was 16 years old and said the day he was captured by the U.S. Army in Italy a year latter was the greatest day of his life. I introduced AL to the factory rep, they talked German for a few minutes and Al turned to me and said the rep was from northern Germany and I'm from Southern Germany and I can't understand anything the Ba***rd is saying. So the Rep was send back to Germany and I can read a little German and with AL's help when I needed it, I got the equipment installed and working. (Wife's mother side of the family are German Jews).
Made a huge change in the QC. I can't remember the year but 1981 or so sounds about right.

What did you do for VW of America ?
Yes, I would love to find one of the aluminum bodies. QC put two bodies together and the rest of the body panels were sent to Westmoreland. The 2 at our plant was scraped. I watched as they were shoved in the large dumpster to be hauled off to the scrap metal place. Scrap metal place had a contract with VW that all of the scrap metal had to be bailed.
 
Last edited:

Twodeaddogs

Well-Known Member
HBA Supporter
Joined
Jan 18, 2009
Messages
899
Location
Dunlavin, County Wicklow,Ireland
The VW Golf Diesel (Rabbit to you guys) was a fine car, I had two. It had no turbo so it wouldn't pull the skin off a sausage but it gave you back 55 mpg all day long, as long as you never tried to overtake a truck on the motorway. Or any other kind of vehicle, for that matter. Except maybe a mobility scooter or a milk float. The engine, if serviced properly, would easily last 250,000 miles and on Irish roads in the 80s, that's saying something. Golfs always had a reputation for being tough, too and they sold in their millions for good reason......as for running diesels on Jet A1, crkckr is perfectly correct. You can do it as long as you add some lubricant, otherwise the first thing you'll ruin is the expensive injection pump. I've known people add oil in the same ratio as for a two-stroke engine; 50 to 1 for old engines, 40 to 1 for newer units.
 

Pops

Well-Known Member
Log Member
Joined
Jan 1, 2013
Messages
8,139
Location
USA.
Remembered when that happen in the news.
 

Kyle Boatright

Well-Known Member
Joined
Nov 11, 2012
Messages
930
Location
Marietta, GA
Shift to first gear, immediately switch the AC off, accelerate through the gears (with lots of patience), then switch AC on. It made a difference.
BJC
I still do that. SWMBO always questions why I'm forever turning the A/C on and off in the car.

How much HP is required to run a typical auto A/C system?
 

BJC

Well-Known Member
HBA Supporter
Joined
Oct 7, 2013
Messages
11,233
Location
97FL, Florida, USA
I still do that. SWMBO always questions why I'm forever turning the A/C on and off in the car.

How much HP is required to run a typical auto A/C system?
I think that the Rabbit AC consumed 5 or 6 HP; a significant percentage of the engine’s 54 HP.


BJC
 
Top