PyroJoes Recipe for Beginners

[metiz]

You can try putting your propane tank in some hot water to get more pressure. It's very close. I've ran the dreadnought on a single propanetank but that engine had an expanded tail. Slapping on an expansion will give you more thrust and a lower min throttle so it's worth the extra work

[ganuganu]

since we have diwali after five days, fabricators are little busy i think he will give the cone tomorrow. I have a doubt here will i get 35pounds of thrust with this engine, the reason why iam asking is welder accepted to place the engine and gas cylinder over the bicycle. And joe shall i make the augmenter which you designed before..

[PyroJoe]

It would be better to continue to work on the fuel system.
As mentioned before it would help considerably if the propane tank was full and warm before each run.

If the fueling system can be made to start and sustain dependably, then build the augmenter.
The augmentor will represent about half the thrust of the engine but will be useless if the engine doesn't run.

[ganuganu]

ya i know. still i didnt fix the engine to the bicycle. I will fix it only after the engine is started and throttled successfully till that iam quiet.

[ganuganu]

i found the problem, the engine actually started i can see it high vibrations and high noise the problem is again there is a leak in the combustion chamber, those are major leaks i will fix it soon and post the video.. Iam sure the engine is success..

[PyroJoe]

Good detect,
Technical inspections are a very useful tool. Even the most talented and trained can miss things on occasion. I hope it gives less trouble on the next try.

[ganuganu]

somehow tried and succeeded in closing all the holes in the engine, now another problem here is temperature its 26 deg celcius. Engine is not giving any response to start acting worse than before. Do you say that its because of low temp here.

I had a doubt and tried to start my 13pounds engine it felt difficult to sustain, actually that engine is quick starter. What do you think?

[PyroJoe]

26 degrees celsius is plenty warm. Is the propane tank near empty?

[ganuganu]

no its 7.5kg of gas. Dont know what to do?????

[PyroJoe]

Need to know the status of the engine.
2 injectors or 4?
where are the injectors placed?
tail cone or no tail cone?

To test the injectors:
Take the injectors off the engine.
Go to a sheltered, fire proof, ventilated area.
Point the injector in a safe direction.
Light the four injectors, slowly open the tank valve. (video if possible)
Should be seeing a roaring flame of equal volume from each.

Poorly crimped ends will have no sustaining flame.

you say low temp, is it cold enough to wear a jacket there?

[ganuganu]

used tail cone
2 injectors
injectors are perfect iam 100% sure
injectors are placed at the tip of he flare

http://youtu.be/G50SxdQLxs0

[PyroJoe]

Do you still have the 4 injector setup?

If so there is a technique I use to diagnose where the trouble is.

The technique requires the 4 injector setup and no blower.

Position1: Typically Good
The injectors work well when placed nearest the tailpipe side of the intake.
This is common among most back enders.

Position2: Moderate to needs more air
Typically the design has a small deficiency in aerodynamic valving, or an overly large intake area.

Position3: Aerodynamic valving is poor
The CC wall is creating a condition that hinders the intake to aerodynamically valve.
The sidewall creates a loss in containment and a high quantity intake leak is occuring nearest the CC wall.

A tolerable engine can start and run in any of the positions.
A moderately tolerable engine can run typically in the Position2.
A failed aerodynamic valve typically will only run in Position3.

With backenders, injector depth can vary from flare to midway into the intake.

Occasionally I will find a batch of propane that has very poor flame speed, and will fail to pass the open air test I described previously. Typically will use that for something else.

[ganuganu]

k do you say that i have to try with a new tank. And does it fail in the open air test.

the video which you saw earlier in which the injector were placed in first position.

[PyroJoe]

Looks like the injectors need a little more crimp. There should be very little "fluffy yellow" slow flame and much more "ripping blue" fast flame. As the tank valve is near full pressure the flame should almost be completely blue and almost fast enough that the flame cannot keep up with the speed of the fuel. Often it will be to fast for the flame to stay lit.

It would be better to have 4 injectors producing ripping fast blue flame, but may not be possible with the setup.

The quality of the gas looks good. The volume looks low for some reason, is it cold there? Maybe there is a fuel restriction somewhere?

[ganuganu]

temp is not that low its about 27 deg c.shall i try with a new cyl.