HX 82 102/255 " Money Pit "

[Chuks]

congratulations Andy.

[Deleted]

May 16, 2019 9:21:33 GMT -5 Chuks said:

congratulations Andy.

Thanks

Here is the second test

[monty]

Andy,

Looks and sounds GREAT!!

Monty

[CH3NO2]

PURE AWESOMENESS!

Great job Andy.

[Deleted]

So the plan was Saturday..... start the engine, see if I could lower the idle setting, see how the engine would react to throttle input and then try the afterburner

So this happen




Not what was expected, so after another try....... it was clear something was not happening. The ignition was firing... fuel was going in but

Only thing to do was pull the engine out. Half expecting to see the injectors burnt away, after all they are a new idea ....... or flametube damage, disappointed but that's what happens
when building your own engines.... some times things go wrong

So the engine was pulled apart


upload image


So..... apart from a little soot on the inside of the front wall .... every thing else, well look better than i could hope. nothing looks like its been getting over hot

So guess it time to check other things....

[madpatty]

May 26, 2019 23:53:13 GMT -5 andym said:

So the plan was Saturday..... start the engine, see if I could lower the idle setting, see how the engine would react to throttle input and then try the afterburner

So this happen




Not what was expected, so after another try....... it was clear something was not happening. The ignition was firing... fuel was going in but

Only thing to do was pull the engine out. Half expecting to see the injectors burnt away, after all they are a new idea ....... or flametube damage, disappointed but that's what happens
when building your own engines.... some times things go wrong

So the engine was pulled apart


upload image


So..... apart from a little soot on the inside of the front wall .... every thing else, well look better than i could hope. nothing looks like its been getting over hot

So guess it time to check other things....

Hi Andy,

The internals couldn't have looked any better than this.

I am wondering what was going on there. Clearly you have rotation(which was there judging from the rotor sound), fuel going inside(from fuel pressure) and igniter firing(not sure) but clearly fuel not igniting(from your temp gauge).

Maybe just that fuel isn't getting ignited due to some reason or maybe you are putting in too little fuel if you already changed the idle fuel flow (idle fuel set too low) that there is not a proper spray or spray isn't reaching the plug.

Sort of reminds me of my engine testing when I was using gaseous fuel for starting and whenever fuel pressure was too low the ignition always got way problematic.  Just replaced it with new gas cylinder and boom, ignited in the first go.

Pretty sure you will sort it out.

Cheers. 


 

[Johansson]

What fuel are you using? Proper aviation kero or the watered down crap they sell as diesel fuel at the gas station?

[Deleted]

May 28, 2019 13:34:01 GMT -5 Johansson said:

What fuel are you using? Proper aviation kero or the watered down crap they sell as diesel fuel at the gas station?

Hi am using Kero.... but mixed with petrol.... which on the last run i added more petrol than before

But perhaps a little to much petrol.... John and I have been chatting over a few ideas....

Did notice i had perhaps dialled fuel pressure back a little to much, or even the addition of too much petrol had thinned the fuel a little and the pump was not working as well ? long shot?

But petrol/gasoline is 0.600 Centistokes Kerosene is 2.5 Centistokes viscosity..... it is not much, but did some testing with ignition today, and got a much reactive reaction from kero
on the plug than petrol ?

So, who knows, will be putting engine back together this week, and see if it wants to fire up perhaps Saturday


Thanks every one

[Johansson]

Keep a blowtorch ready in case it fails to ignite again, too bad to have to abort a test run just because the fuel wont ignite.

[turboron]

Andy, when I first tried to start my DIY I had several issues. I solved part of the problem by grounding the ignitor directly to the battery post with a lower gauge wire. My spark plug was also bridging from the terminal to the side. I always clean the plug before each start. I have a higher voltage system waiting to be implemented one day.

Thanks, Ron

[CH3NO2]

Hi Andy,

The hardware all looks 1st class in design, fabrication and post firing condition. The one big variable that changed since it was last fired is the addition of the after burn chamber section.

Could this have something to do with the starting difficulty? Perhaps reducing the air mass flow rate and causing excessive fuel richness at the spark gap location?

Tony

[Deleted]

May 29, 2019 7:26:31 GMT -5 turboron said:

Andy, when I first tried to start my DIY I had several issues. I solved part of the problem by grounding the ignitor directly to the battery post with a lower gauge wire. My spark plug was also bridging from the terminal to the side. I always clean the plug before each start. I have a higher voltage system waiting to be implemented one day.

Thanks, Ron

Hi Ron

had hoped with this ignition i would not have any issues



Will soon know, should be testing again Saturday

Thanks Andy

[Deleted]

May 29, 2019 3:23:00 GMT -5 Johansson said:

Keep a blowtorch ready in case it fails to ignite again, too bad to have to abort a test run just because the fuel wont ignite.

Yep.... will give it a few more tries, with better kero mix, and hope the issue is no more

[Deleted]

May 29, 2019 7:40:44 GMT -5 CH3NO2 said:

Hi Andy,

The hardware all looks 1st class in design, fabrication and post firing condition. The one big variable that changed since it was last fired is the addition of the after burn chamber section.

Could this have something to do with the starting difficulty? Perhaps reducing the air mass flow rate and causing excessive fuel richness at the spark gap location?

Tony

Yep did cross my mind. But speaking to John we don't think so, time will see.... next start will be with out A/B then after that i will refit ?

well only if the next start works

[Deleted]

So after a failed test last week here is the update.... sorry about the sound being a little out of sync. But i hope you enjoy.. do need to drain a little oil, increase the rev's on the oil pump... but it is only running at 50% as it is now, so plenty of room for improvement