Evolution 46 HELP!!!
#1
Thread Starter
Senior Member
Joined: Dec 2005
Posts: 553
Likes: 0
Received 0 Likes
on
0 Posts
From: Chewelah, WA
I have a new Evolution 46. It will idle like a dream jump to high speed. Run at high speed great and then quite if I don’t cut the throttle back. Once I get it to run good at high speed I lift the plane up, runs good tip it down the engine wants to die. I tipped it down and adjusted the high speed needle until it ran good, tip it up the rpm changes but still runs. In flight it will run good all day at ½ throttle. At high speed it will run for a short wile then quite if I don’t cut it back to ½ throttle. Could this be the glow plug?
#2
This doesn't sound like a glow plug issue to me, PA BEN. My first impression was that the high speed needle is simply too lean.
If you're confident that you have the high speed needle set rich enough and the engine isn't really hot when it quits running, I'd recommend you go back through your fuel lines and fuel tank plumbing.
I had a similar problem with a Magnum XLS .52A that would idle and transition great, but would die when I revved it up to full throttle. I found I had a split in the fuel line inside the tank that connected to the clunk. The engine could draw enough fuel to idle, but as I revved it up the tear in the fuel line would prevent it from drawing enough fuel to keep running.
Good luck.
If you're confident that you have the high speed needle set rich enough and the engine isn't really hot when it quits running, I'd recommend you go back through your fuel lines and fuel tank plumbing.
I had a similar problem with a Magnum XLS .52A that would idle and transition great, but would die when I revved it up to full throttle. I found I had a split in the fuel line inside the tank that connected to the clunk. The engine could draw enough fuel to idle, but as I revved it up the tear in the fuel line would prevent it from drawing enough fuel to keep running.
Good luck.
#3

Joined: Apr 2006
Posts: 2,275
Likes: 0
Received 0 Likes
on
0 Posts
From: Warialda NSW, AUSTRALIA
G'day Mate,
When you lift the nose up, at full throttle, if it is rich enough, the engine should pick up some revs, if it does it's ok to fly, if not, richen HS mixture until it does gain some revs, when nose lifted.
No reason not to change glow plug, if in doubt. they are cheaper than a new plane if the engine cuts, just after take off.
When you lift the nose up, at full throttle, if it is rich enough, the engine should pick up some revs, if it does it's ok to fly, if not, richen HS mixture until it does gain some revs, when nose lifted.
No reason not to change glow plug, if in doubt. they are cheaper than a new plane if the engine cuts, just after take off.
#4
Thread Starter
Senior Member
Joined: Dec 2005
Posts: 553
Likes: 0
Received 0 Likes
on
0 Posts
From: Chewelah, WA
I can lift the nose up runs fine, nose down wants to die. Also the fuel tank is lower then the carb. Would this cause this? I took a Magnum 70 off and put the Evolution on it ran great then I crashed it. Before the crash the engine was side ways now strate up.


#5

My Feedback: (3)
How old is the .46NT? Was this the original plug that came with the engine?
Mine always runs great. Peak your highspeed needle valve and then back off at least 300 RPM. Also, I would suggest trying an OS A3 plug in this particular engine. Some people will tell you that the OS 8 is the perfect plug, but it isn't for most Evolution engines. They like hotter plugs. You may find it solves your issues and gains quite a bit more power. I haven't tried the A3 yet because a friend gave me a few of the older type of Tower's plugs. I'll go to the A3 when those are gone. I ran the Evo .455 with a Saito SS plug, but I didn't see as good of an improvement as with those older plugs. The newer Tower's plugs seem to be colder and not much of an improvement, and is the same as the Saito plugs.
If you rebuild, check the tank and lines like Biged suggested.
Mine always runs great. Peak your highspeed needle valve and then back off at least 300 RPM. Also, I would suggest trying an OS A3 plug in this particular engine. Some people will tell you that the OS 8 is the perfect plug, but it isn't for most Evolution engines. They like hotter plugs. You may find it solves your issues and gains quite a bit more power. I haven't tried the A3 yet because a friend gave me a few of the older type of Tower's plugs. I'll go to the A3 when those are gone. I ran the Evo .455 with a Saito SS plug, but I didn't see as good of an improvement as with those older plugs. The newer Tower's plugs seem to be colder and not much of an improvement, and is the same as the Saito plugs.
If you rebuild, check the tank and lines like Biged suggested.
#6
Thread Starter
Senior Member
Joined: Dec 2005
Posts: 553
Likes: 0
Received 0 Likes
on
0 Posts
From: Chewelah, WA
ORIGINAL: blw
How old is the .46NT? Was this the original plug that came with the engine?
Mine always runs great. Peak your highspeed needle valve and then back off at least 300 RPM. Also, I would suggest trying an OS A3 plug in this particular engine. Some people will tell you that the OS 8 is the perfect plug, but it isn't for most Evolution engines. They like hotter plugs. You may find it solves your issues and gains quite a bit more power. I haven't tried the A3 yet because a friend gave me a few of the older type of Tower's plugs. I'll go to the A3 when those are gone. I ran the Evo .455 with a Saito SS plug, but I didn't see as good of an improvement as with those older plugs. The newer Tower's plugs seem to be colder and not much of an improvement, and is the same as the Saito plugs.
If you rebuild, check the tank and lines like Biged suggested.
How old is the .46NT? Was this the original plug that came with the engine?
Mine always runs great. Peak your highspeed needle valve and then back off at least 300 RPM. Also, I would suggest trying an OS A3 plug in this particular engine. Some people will tell you that the OS 8 is the perfect plug, but it isn't for most Evolution engines. They like hotter plugs. You may find it solves your issues and gains quite a bit more power. I haven't tried the A3 yet because a friend gave me a few of the older type of Tower's plugs. I'll go to the A3 when those are gone. I ran the Evo .455 with a Saito SS plug, but I didn't see as good of an improvement as with those older plugs. The newer Tower's plugs seem to be colder and not much of an improvement, and is the same as the Saito plugs.
If you rebuild, check the tank and lines like Biged suggested.
#8

My Feedback: (3)
Be critical when you swap out plugs. Look for the engine to fire up and take full throttle right away. Look for signs of it stumbling, blubbering, or just not running smoothly. This is a dead giveaway on these particular engines, along with the Evo .455. I would stick with the A3, but am curious now about the H9 plug. Let me know, okay?
#9
I believe McCoy makes the Hangar 9 plugs... I have noticed that the H9 "Super Plug" that comes installed in the Evo 2 strokes looks just like a 4 stroke plug. I have a feeling that it's probably the McCoy 4 stroke plug? That would figure, right? The Evo seems to like a hotter plug, and the long reach works well in the Evo head that has an angled plug hole.
#10

My Feedback: (3)
Yes, they do like hotter plugs. Mine came with an OS 8 plug. I don't know what the .455 came with because I bought it off of a friend.
I wish I had tached my engine the day I put the older Tower's plug in the .46NT because I really would like to know how much power I gained. It was a huge leap for that engine. Maybe it was just mine, but it was a lot.
I wish I had tached my engine the day I put the older Tower's plug in the .46NT because I really would like to know how much power I gained. It was a huge leap for that engine. Maybe it was just mine, but it was a lot.
#11
Thread Starter
Senior Member
Joined: Dec 2005
Posts: 553
Likes: 0
Received 0 Likes
on
0 Posts
From: Chewelah, WA
Ok the hotter glow plug helped but it still dies at hi speed. It will run all day at half throttle. Which is plenty for this Plane “Heckley”. So I put another Evolution 46 on that I know is broke in and runs good. It will fun good at full throttle, but after I fly a wile the engine will cough but not die and when I do loops or rolls at full power it will cough but in a hover or a slow striate climb out it will not cough could the be a foaming issue? The new engine will die but the broke in engine will cough?
#12

Joined: Jan 2003
Posts: 258
Likes: 0
Received 0 Likes
on
0 Posts
From: Ovilla,
TX
I've been having a similar problem with my Evo 46's in a twin. At 3/4 throttle the engines will quit. I started to remove & replace the fuel tanks since I thought it might be a fuel foaming problem. Will change to A3's & report back.
Also Pa Ben: Can you see if any bubbles are in the fuel line when the engine is running? Just wanted you to check for fuel foaming issues.
Also Pa Ben: Can you see if any bubbles are in the fuel line when the engine is running? Just wanted you to check for fuel foaming issues.
#13
Thread Starter
Senior Member
Joined: Dec 2005
Posts: 553
Likes: 0
Received 0 Likes
on
0 Posts
From: Chewelah, WA
Yes I see some bubbles. But on the bench at full throttle it doesn’t quite or show signs of foaming. Only in the air flying. I’ve checked the tank for leaks by the way.
#15

Joined: Jan 2003
Posts: 258
Likes: 0
Received 0 Likes
on
0 Posts
From: Ovilla,
TX
I'm at work right now, but will get back to you guys in the next couple of days. Will replace the fuel line from remote needle valve to carb and check out the tanks for leaks, then replace the glow plugs with A3's. (One step at a time)
If that all looks okay, I'm gonna replace the tanks with smaller ones, and report back.
Pa Ben:
From your pictures, it looks like the fuel tank is lower than the carb. Got an idea about how much lower? If I remember correctly, the standard rule of thumb is: the centerline of the tank should be at the same level as the centerline of the carb's throttle barrel. If it is much lower, it can cause lean runs, especially if you pull high g maneuvers.
If that all looks okay, I'm gonna replace the tanks with smaller ones, and report back.
Pa Ben:
From your pictures, it looks like the fuel tank is lower than the carb. Got an idea about how much lower? If I remember correctly, the standard rule of thumb is: the centerline of the tank should be at the same level as the centerline of the carb's throttle barrel. If it is much lower, it can cause lean runs, especially if you pull high g maneuvers.
#16
Thread Starter
Senior Member
Joined: Dec 2005
Posts: 553
Likes: 0
Received 0 Likes
on
0 Posts
From: Chewelah, WA
ORIGINAL: Prairie Mike
I'm at work right now, but will get back to you guys in the next couple of days. Will replace the fuel line from remote needle valve to carb and check out the tanks for leaks, then replace the glow plugs with A3's. (One step at a time)
If that all looks okay, I'm gonna replace the tanks with smaller ones, and report back.
Pa Ben:
From your pictures, it looks like the fuel tank is lower than the carb. Got an idea about how much lower? If I remember correctly, the standard rule of thumb is: the centerline of the tank should be at the same level as the centerline of the carb's throttle barrel. If it is much lower, it can cause lean runs, especially if you pull high g maneuvers.
I'm at work right now, but will get back to you guys in the next couple of days. Will replace the fuel line from remote needle valve to carb and check out the tanks for leaks, then replace the glow plugs with A3's. (One step at a time)
If that all looks okay, I'm gonna replace the tanks with smaller ones, and report back.
Pa Ben:
From your pictures, it looks like the fuel tank is lower than the carb. Got an idea about how much lower? If I remember correctly, the standard rule of thumb is: the centerline of the tank should be at the same level as the centerline of the carb's throttle barrel. If it is much lower, it can cause lean runs, especially if you pull high g maneuvers.
#17
Senior Member
My Feedback: (3)
Joined: Dec 2004
Posts: 1,486
Likes: 0
Received 0 Likes
on
0 Posts
From: Martinsville,
IN
Once I get it to run good at high speed I lift the plane up, runs good tip it down the engine wants to die. I tipped it down and adjusted the high speed needle until it ran good, tip it up the rpm changes but still runs. In flight it will run good all day at ½ throttle. At high speed it will run for a short wile then quite if I don’t cut it back to ½ throttle. Could
Since pointing down or up and changing running so drastically tells you it is all about tank. Have you even touched the low speed needle ? Your fix will be ,side mount the engine, or even inverted to get carb down in level.............
#18
Thread Starter
Senior Member
Joined: Dec 2005
Posts: 553
Likes: 0
Received 0 Likes
on
0 Posts
From: Chewelah, WA
Thats my next move. Thanks. It's a fun plane, and flys real nice with this engine. I had a magnum 70 on it before, made it to heavy.



