# Pulse Jet Engine new improved design.



## Rocket Man (Mar 21, 2014)

Experimenting with pulse jet engines has been very educational for many years. I am tired of building piston engines I have 18 of them. Now I have 14 pulse jet engines and 1 rocket engine. I put all I know into this new engine body design. Using the stock Dyna Jet head, the stock factory fuel orifice, the new engine produces a full 6 lbs of thrust on gasoline. The factory engine claims 5 lbs of thrust but it really produces only 4 lbs of thrust. 

I started out experimenting with the factory Dyna Jet head with my new engine body design. I expected it would destroy the .006" reed valves and it did. The new engine body produces 5 lbs of thrust on gasoline and the reed valves lasted about 3 minutes on the test stand. 

Next I replaced the factory reed valve retainer with my new reed valve retainer design and tested the engine again. Reed valves open .200". The engine ran for 4 minutes on the test stand, no damage to the reed valve, reed valves show no signs of getting hot either, thrust is 5.250 lbs.

Next I tried a .008 reed valve thrust is down to 4.75 lbs of thrust. No damage to the reed valve.

Next I tried a .010 reed valve engine will not start.

.006 reed valves is working the best so I continued to experiment with it. I rounded the tips of the new retainer so it matches the round tips of the reed valve. The engine produces 5.75 lbs of thrust on gasoline. It ran 4 minutes and no damage to the reed valves.

Next I opened the reed valve retainer up to .230" using the same .006 reed valve again. The engine produced a full 6 lb of thrust for 4 minutes on gasoline.

Some of my best information comes from an engineering book called, Liquid Fuel Rocket Engine Technology. Dyna Jet engine combustion chamber is too short for the burn rate of gasoline. The diffuser on the tip of the exhaust pipe gives the engine more pushing power. A Pulse Jet engine is really a liquid fuel rocket engine that runs on AIR and LIQUID fuel.

I have not tried a larger fuel orifice yet and I have not tried Alcohol yet. My math shows this engine will produce 8.4 lbs of thrust on alcohol.

Photos shows the new engine body next to a factory made dyna jet body. The new body is made from 24 gauge steel welded with an 80 amp Harbor Freight wire flux welder.

I have redesigned the factory fuel flow jector so it has a needle valve. This is a big improvement over the trial and guess method by switching the fuel injectors to see which one works best for your altitude, geographical location, humidity, air temperature. The engine starts very easy on any fuel, propane, gasoline, gas/kerosene, gas/diesel, Methyl Alcohol at 20% throttle and can be throttle up to 100% throttle with the needle valve.

The test stand is a 7"x21" railroad car on a 36" long RR track. Fuel tank is on the front if the RR car. The car pushes a bell crank the pulls down on the scale.

I built a new engine head this design is so much easier to build, it saves about 10 hours work and it works just as well as the original factor head.

I have been building my own reed valves from Blue String steel. Brand new very sharp aviation snips work great for cutting these parts out. One sheet of blue spring steel will make 30 reed valves. I don't need all these reed valves anymore improvements to the engine makes the reed valve last for many hours. They use to last only 3 to 4 minutes before they were totally destroyed.

http://i43.photobucket.com/albums/e358/gary350/pj1_zps41ccc811.jpg

http://i43.photobucket.com/albums/e358/gary350/IMG_20140314_162639_549_zps84266ae9.jpg

http://i43.photobucket.com/albums/e358/gary350/IMG_20140314_162602_163_zps8529c732.jpg

http://i43.photobucket.com/albums/e358/gary350/SR-71-5.jpg

http://i43.photobucket.com/albums/e358/gary350/IMG_20140302_105004_879_zpscab3af0a.jpg

http://i43.photobucket.com/albums/e358/gary350/IMG_20140305_212501_137_zpsfd04a429.jpg

http://i43.photobucket.com/albums/e358/gary350/PJ-5-6.jpg

http://i43.photobucket.com/albums/e358/gary350/RV-005.jpg

http://i43.photobucket.com/albums/e358/gary350/RV-006.jpg

http://i43.photobucket.com/albums/e358/gary350/RV-007.jpg

http://i43.photobucket.com/albums/e358/gary350/RV-008.jpg

http://i43.photobucket.com/albums/e358/gary350/DJ-RV.jpg

http://i43.photobucket.com/albums/e358/gary350/orifice_zps26c88ed4.png

http://i43.photobucket.com/albums/e358/gary350/IMG_20140311_102136_310_zps85d36bc7.jpg

http://i43.photobucket.com/albums/e358/gary350/IMG_20131113_193736_645_zps87036fea.jpg

Bending fixture.

http://i43.photobucket.com/albums/e358/gary350/bendingfixture_zps7fe0d1b8.png

I also have a 20 lb thrust engine.

http://i43.photobucket.com/albums/e358/gary350/000_0043.jpg

http://i43.photobucket.com/albums/e358/gary350/000_0044.jpg

http://i43.photobucket.com/albums/e358/gary350/000_0045.jpg

I have built a 100 lb thrust pulse jet engine too.

http://i43.photobucket.com/albums/e358/gary350/IMG_20131008_125303_590_zps8aaf3ccf.jpg

http://i43.photobucket.com/albums/e358/gary350/IMG_20130802_214911_685_zpsa37faf84.jpg

http://i43.photobucket.com/albums/e358/gary350/FuelSystem_zpse916355f.png

Next project is a 900 lb thrust pulse jet engine.

http://i43.photobucket.com/albums/e358/gary350/photo-1_zps3d1a8464.jpg

http://i43.photobucket.com/albums/e358/gary350/photo-4_zps65138c2e.jpg

Videos

https://www.youtube.com/watch?v=1VNyTsUT2Xg

https://www.youtube.com/watch?v=pwz7AvufWG4

https://www.youtube.com/watch?v=1uMttzqoGo0

https://www.youtube.com/watch?v=lt7V0yrHc_w


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## RonGinger (Mar 21, 2014)

Wow! I went through all your photobucket images, you have done a lot of interesting things. I like the camper and the TV antenna. I live in a fringe area and have to pay for cable to get any TV- does that antenna work for all the standard TV channels?


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## Rocket Man (Mar 21, 2014)

RonGinger said:


> Wow! I went through all your photobucket images, you have done a lot of interesting things. I like the camper and the TV antenna. I live in a fringe area and have to pay for cable to get any TV- does that antenna work for all the standard TV channels?



That antenna will pick up all the TV stations up to 50 miles crystal clear and 65 miles very good. I cancelled cable TV many years ago. I receive 44 channels free, and it is good stuff and movies too. If you build that antenna use a 48"x48" reflector screen it works even better. Buy some top rail for chain link fence the 1.250" pipe fits together end to end so you can make a 30 Ft TV tower for $30. Put a flat washer at each pipe connect, drill 3 evenly spaced holes 1/4" dia for cables to hold up the tower. 

I have another photo bucket page too loaded with just as much stuff. And my computer still has a lot of my stuff but I did loose 100s of photos when the hard drive crashed once. I have built over 400 projects in the past 40 years. Some are old style pictures on photographic paper. I have a lot of hot air fans, hot air engines, steam engines from .500" bore up to 4" bore, electric engine, tesla coils, BB machine guns, rockets, airplanes, go karts, mini bikes, bicycles, and more. I made plans for every project. It accidently turned out to be a good retirement plan for ebay.


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## apointofview (Mar 27, 2014)

Can you give me a link to the other projects would be neat to see them


Sent from my iPhone using Model Engines


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## Rocket Man (Mar 28, 2014)

apointofview said:


> Can you give me a link to the other projects would be neat to see them
> 
> 
> Sent from my iPhone using Model Engines



Click the photos to photo bucket and go there you can look at all the photos I have listed.

Click the videos you can see all my videos on YouTube.

 I have photos on another photobucket account but you can not go there unless I post a pic from that list of photos.  

 I have photos on my computer but no place to upload all of them.

 I have 100s of color slide film, old super 8 movie film, black and white photos, and color photos in a box.


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