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Feb 12, 2020, 12:17 PM
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Thread OP
no. once it's closed it's closed. i suspect a moderator can reopen it but otherwise....
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Feb 12, 2020, 12:42 PM
Still gassin' it.
Then the issue is moot...

By the way, today messed with the radial, drilled three tiny holes in the intake boss, intended to blow the oil, clinging to the wall, back into the airstream, in hope of getting a better mixture distribution.

It seems to have helped, engine seems to be running more "round" in the midrange, gained 200~300 RPM top end, and the oil from the crankcase drain has considerably brightened up.

However, got a few strange quirks back: around 5K RPM, cylinder 5 seems to drop, but comes back around 4K, where cylinder 2 seems to drop, and around 3K all cylinders are firing again.
Very strange, and I have to look into that.

Improved fuel distribution (1 min 21 sec)
Feb 12, 2020, 02:24 PM
Whats that drip ?
ClubFlyer's Avatar
Quote:
Originally Posted by 1967Brutus

By the way, today messed with the radial, drilled three tiny holes in the intake boss, intended to blow the oil, clinging to the wall, back into the airstream, in hope of getting a better mixture distribution.

It seems to have helped, engine seems to be running more "round" in the midrange, gained 200~300 RPM top end, and the oil from the crankcase drain has considerably brightened up.

However, got a few strange quirks back: around 5K RPM, cylinder 5 seems to drop, but comes back around 4K, where cylinder 2 seems to drop, and around 3K all cylinders are firing again.
Very strange, and I have to look into that.

https://www.youtube.com/watch?v=USXAiRpQ9Jk&t=5s

So you introduced a fixed air bleed into the intake?
Last edited by ClubFlyer; Feb 12, 2020 at 03:13 PM.
Feb 12, 2020, 02:32 PM
Registered User
Quote:
Originally Posted by 1967Brutus
Even for a closed account?
Your account is not suspended whatsoever.
it was you who asked the admin to close it down because you had a 'hot' discussion with him
Now if you want to get your account back you just need to contact the same admin.
anyway you cannot have two active accounts and the admin will likely ban either of them.
if the admin had a bad day and thinks you are a troll he will suspend both accounts
in this case do not contact him with your current account and use an email instead (PM me if you want)
but if you are happy enough with your current account then it's fine.
Feb 12, 2020, 03:56 PM
Still gassin' it.
Quote:
Originally Posted by coreless
Your account is not suspended whatsoever.
it was you who asked the admin to close it down because you had a 'hot' discussion with him
Now if you want to get your account back you just need to contact the same admin.
anyway you cannot have two active accounts and the admin will likely ban either of them.
if the admin had a bad day and thinks you are a troll he will suspend both accounts
in this case do not contact him with your current account and use an email instead (PM me if you want)
but if you are happy enough with your current account then it's fine.
It is a bit beyond me why you bring it up in the first place, and go on about it in the second, actually…

I am totally happy the way things are right now
Feb 12, 2020, 03:59 PM
Still gassin' it.
Quote:
Originally Posted by ClubFlyer
So you introduced a fixed air bleed into the intake?
Yup... It seems to work, at least the behaviour of the engine has improved pretty much in most of the midrange, in that the engine seems to run more smooth and consistent.
Still have to figure out why at different throttle positions different cylinders seem to drop, but other than that, temperature between cylinders are much more balanced.
Feb 12, 2020, 05:14 PM
Registered User
Quote:
Originally Posted by 1967Brutus
I am totally happy the way things are right now
I didn't realize until today that you had another new account
your account is only 2 months old and your posts counter is already nearly 1000 posts
it's clear enough that you can't live without RCG for a second
it's ok if you feel good with this account but I thought you might actually use the other one
unless you want to preserve your older account just in case you get this one banned.
all this said, welcome back to the forum and enjoy it as much as you can until FAA shut the hobby down
Feb 12, 2020, 05:37 PM
Registered User
Thread OP
So replacing the fuel hose fixed it. I've now got 70 ounces of fuel thru it and it's idling at 1200, peaking at 7500. Cht never topped 240f. I think I've got a winner here.

Sent from my Pixel 2 using Tapatalk
Feb 12, 2020, 07:19 PM
Whats that drip ?
ClubFlyer's Avatar
Quote:
Originally Posted by 1967Brutus
Yup... It seems to work, at least the behaviour of the engine has improved pretty much in most of the midrange, in that the engine seems to run more smooth and consistent.
Still have to figure out why at different throttle positions different cylinders seem to drop, but other than that, temperature between cylinders are much more balanced.

Saito had an issue with dropping cylinders with their early Radials, due to fuel distribution issues. ASP uses a distribution rotor, so the cylinders get better contribution of the air/ fuel mixture. Possibly the air/fuel mixture leans at those throttle settings, since you are running on gas with a much leaner air/fuel ratio, the engine is more sensitive to lean mixtures than would be with methanol / glow fuel. Have you tried changing the Solenoid duty cycle at those throttle positions to see if the dropped cylinder issue improves?
Feb 12, 2020, 11:12 PM
Still gassin' it.
Quote:
Originally Posted by raleighcopter
So replacing the fuel hose fixed it. I've now got 70 ounces of fuel thru it and it's idling at 1200, peaking at 7500. Cht never topped 240f. I think I've got a winner here.

Sent from my Pixel 2 using Tapatalk
Pfhew! Happy it was just the tubing, you got me worried there for a moment...

Yup... you definitely have... Now remember, when you get it in a plane, to richen up the upper 3/4 (everything above say, 3000 RPM) of the throttle range a touch before first flight. Rich engines Run, lean engines quit when running gasoline.

Your engine shows real good numbers, especially WRT temperatures, mine all run noticable hotter. Congrats!

Now all I can say is: happy flights, MANY happy flights (and if you are anything like me, it will rack up the hours like no other).

By the way, 70 oz… that's quite a bit. For me that would be close to 7 hours of actual flying time... You seem to really like running it
Last edited by 1967Brutus; Feb 13, 2020 at 03:06 AM.
Feb 12, 2020, 11:23 PM
Still gassin' it.
Quote:
Originally Posted by coreless
your account is only 2 months old and your posts counter is already nearly 1000 posts
it's clear enough that you can't live without RCG for a second
It is not that I cannot live without RCGroups. It is that I have a slight case of Aspergers, and my mind is basically 24/7 in "problem solving mode", and my job, on the most of demanding days only takes one or two hours of that time. What to do with the remaining 22 hrs?

Messing with engines and helping others…

But I can live without RCGroups, no probs, I just need to find something else to occupy my mind with.
Feb 12, 2020, 11:32 PM
Still gassin' it.
Quote:
Originally Posted by ClubFlyer
Saito had an issue with dropping cylinders with their early Radials, due to fuel distribution issues. ASP uses a distribution rotor, so the cylinders get better contribution of the air/ fuel mixture. Possibly the air/fuel mixture leans at those throttle settings, since you are running on gas with a much leaner air/fuel ratio, the engine is more sensitive to lean mixtures than would be with methanol / glow fuel. Have you tried changing the Solenoid duty cycle at those throttle positions to see if the dropped cylinder issue improves?
Actually, it was Saito that in their early radials used a distribution rotor, don't know if they still do.
The ASP just has 5 stationary, spiral shaped intake channels.
They serve to create a low point and a high point in each channel, so fluid can never directly flow from carb to combustion chamber during standstill. That spiral shape is an anti-flooding measure.

And yes, I have tried to get those cylinders to come back by ricing up the mixture, but somehow that doesn't work. A cylinder dropping like that, can only be because of fuel shortage, but strangely enough, the engine does not sound as if one cylinder is not playing along. so it is somehow firing, it is just not developing heat.

So I have to take a look at the actual gas flow pattern in that intake system to figure out what causes it. Maybe I plug up the holes again, and fit a freewheeling mini-turbine in the plenum to mechanically distribute the mixture, or maybe I need to fit the carb straight on the intake (which I rather would not do because the originally designed placement of the carb is an anti-flooding measure).
Feb 22, 2020, 05:06 PM
Registered User
Read the whole thread, learned alot. Special thanks to Bert for some offline help too!

raleighcopter, I'm looking forward to hearing how the high voltage driver turns out. I run life a123 batts on all my gassers.

Unfortunately my Spectrum DX8 gen1 Transmitters do not have curve programming in aero mode (except for throttle channel) to facilitate the use of the fuel solenoid. I REALLY don't want to fly my planes in heli mode but it's looking like I may have to if I want to join in the game using my current gear.

I have little heli knowledge. Can I use the pitch curve to control the solenoid and still have differential ailerons, gear, flaps and the rest?
Feb 22, 2020, 05:12 PM
Registered User
Thread OP
I've been incredibly busy with work and home projects. As a result, I haven't spent time on the Arduino driver. I did manage to install a new cooktop (adding gas and reducing the rough opening in my counter top) as well as lighting in my kitchen so all that's left is painting. Still need to finish a radio repair too Hopefully I'll be back on it shortly.

Regarding your transmitter, I don't run spektrum but I'd imagine it can be programmed one way or another.

Sent from my Pixel 2 using Tapatalk
Feb 22, 2020, 05:17 PM
Registered User
Nice work!


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