R/C Tech Forums

Go Back   R/C Tech Forums > General Forums > Nitro Off-Road

Reply
 
Thread Tools Search this Thread
Old 05-20-2009, 08:27 AM   #1
Tech Apprentice
 
Join Date: Nov 2008
Location: Tampa, FL
Posts: 89
Trader Rating: 6 (100%+)
Default Engine Cutting out When Applying Throttle

Hello, I've got an 8ight RTR with the Mach engine. Just getting around to trying to break it in. It will start up and idle fine, however as soon as I go to give it gas, it cuts out. I assume it is way rich as shipped from the factory, however I tried leaning out the low speed screw some with no success. If it idles, I can actually pour fuel out of the pipe, which is why I figured it's way too rich. I also tried going back to factory settings 2.5 out from bottom with no success. I figured I'd ask first before screwing anything up. Any advice?
__________________
Mitch B
MitchFX is offline   Reply With Quote
Old 05-20-2009, 08:33 AM   #2
Tech Lord
 
Jaz240's Avatar
R/C Tech Elite Subscriber
 
Join Date: Aug 2008
Location: Dwindle city
Posts: 12,492
Trader Rating: 52 (100%+)
Default

Try an hour leaner on the HSN..sometimes its too rich up top..make sure you have good smoke from the pipe..what fuel and % are you using?
__________________
nothing to see here................................
Jaz240 is offline   Reply With Quote
Old 05-20-2009, 08:39 AM   #3
Tech Apprentice
 
Join Date: Nov 2008
Location: Tampa, FL
Posts: 89
Trader Rating: 6 (100%+)
Default

Thanks Jaz, I actually tried an hour or two up top as well, with no luck. I'm using Nitrotane 20% Race. I'm not getting smoke, presumably because it's just idling and I can't get any acceleration without it shutting down.
__________________
Mitch B
MitchFX is offline   Reply With Quote
Old 05-20-2009, 08:47 AM   #4
Tech Lord
 
Jaz240's Avatar
R/C Tech Elite Subscriber
 
Join Date: Aug 2008
Location: Dwindle city
Posts: 12,492
Trader Rating: 52 (100%+)
Default

Change the glowplug..dont check it, just change it..I am not too familiar with the 427 engine but it can only be a few things..Your tune, your clutch/bearings, your glow plug, or an air leak..

Is the engine new?
__________________
nothing to see here................................
Jaz240 is offline   Reply With Quote
Old 05-20-2009, 08:57 AM   #5
Tech Apprentice
 
Join Date: Nov 2008
Location: Tampa, FL
Posts: 89
Trader Rating: 6 (100%+)
Default

Yep, it's a new engine, new buggy, never been run. I changed out the glow plug with the same results. Could the clutch be worn out from idling for various amounts of time trying to get this thing running? Supposedly this engine is the easiest to tune, but for my first nitro experience I'm about to take a hammer to it!
__________________
Mitch B
MitchFX is offline   Reply With Quote
Old 05-20-2009, 09:16 AM   #6
Tech Lord
 
Jaz240's Avatar
R/C Tech Elite Subscriber
 
Join Date: Aug 2008
Location: Dwindle city
Posts: 12,492
Trader Rating: 52 (100%+)
Default

No if everything is new, it should be fine..It has to be either your tune or an air leak..Air leaks can come from the gas tank, the fuel line, or somewhere on the engine..Its really hard to help on-line without being able to see, hear your engine. It may be something stupid like a broken Clutch shoe spring, or your carb is not seated all the way into your engine..Sometimes the people that put them together make mistakes..You should try and find someone local to help you...or try the Losi eight thread..Good luck
__________________
nothing to see here................................
Jaz240 is offline   Reply With Quote
Old 05-20-2009, 09:23 AM   #7
Tech Apprentice
 
Join Date: Nov 2008
Location: Tampa, FL
Posts: 89
Trader Rating: 6 (100%+)
Default

I figured it was probably an air leak or the clutch. From my experience tuning jet skis, it would still run, just run rough. This thing has been nothing but issues from the start. So much for it being "RTR"
__________________
Mitch B
MitchFX is offline   Reply With Quote
Old 05-20-2009, 09:26 AM   #8
Tech Lord
 
Jaz240's Avatar
R/C Tech Elite Subscriber
 
Join Date: Aug 2008
Location: Dwindle city
Posts: 12,492
Trader Rating: 52 (100%+)
Default

99 out of 100 times its just something silly and stupid..these things happen, welcome to Nitro RC..Dont get discouraged, it'll be fine
__________________
nothing to see here................................
Jaz240 is offline   Reply With Quote
Old 05-20-2009, 09:41 AM   #9
Tech Apprentice
 
Join Date: Nov 2008
Location: Tampa, FL
Posts: 89
Trader Rating: 6 (100%+)
Default

Any idea where to start? I've put a few tanks through it just trying to tune it, get it to accelerate, which I can't imagine is real good for it. Should I yank the engine off and check the clutch?
__________________
Mitch B
MitchFX is offline   Reply With Quote
Old 05-20-2009, 09:44 AM   #10
Tech Elite
 
Join Date: Mar 2009
Location: Aurora, Colorado
Posts: 3,644
Default

When you pull the trigger what does it do?

Do it take off quick and boggs or slow down (go one hour lean on HSN)

or

Do it bearly take off (go one hour lean on the LSN)
__________________
TLR - Spektrum - Horizon - TLR 8ight 4.0 - TLR 8ight-T 4.0 - TLR 22 4.0 - Orion
token is offline   Reply With Quote
Old 05-20-2009, 09:47 AM   #11
Tech Fanatic
 
mfrosty's Avatar
 
Join Date: Jan 2009
Location: Baltimore
Posts: 920
Trader Rating: 14 (89%+)
Default

Keep leaning the top an hour at a time until you can keep it running getting into the upper % of the throttle. Sometimes factory setting are WAY too rich. Like my +4 I'm breaking in now. I've went 1/4 turn on both the bottom and top to keep the temps around 200, and that's with the head wrapped in foil!
__________________
~TQ Racing~O.S. Engines~AKA~Answer R/C~
http://www.youtube.com/user/frostyone1977
mfrosty is offline   Reply With Quote
Old 05-20-2009, 09:57 AM   #12
Tech Apprentice
 
Join Date: Nov 2008
Location: Tampa, FL
Posts: 89
Trader Rating: 6 (100%+)
Default

Quote:
Originally Posted by token View Post
When you pull the trigger what does it do?

Do it take off quick and boggs or slow down (go one hour lean on HSN)

or

Do it bearly take off (go one hour lean on the LSN)

It doesnt take off at all, as soon as I start pulling the throttle it cuts off. Doesnt matter how slight of a pull, it will shut off.
__________________
Mitch B
MitchFX is offline   Reply With Quote
Old 05-20-2009, 10:02 AM   #13
Tech Apprentice
 
Join Date: Nov 2008
Location: Tampa, FL
Posts: 89
Trader Rating: 6 (100%+)
Default

Quote:
Originally Posted by mfrosty View Post
Keep leaning the top an hour at a time until you can keep it running getting into the upper % of the throttle. Sometimes factory setting are WAY too rich. Like my +4 I'm breaking in now. I've went 1/4 turn on both the bottom and top to keep the temps around 200, and that's with the head wrapped in foil!

Frosty, I probably went the equivalent of a 1/4 turn at 1 hr increments yesterday and got the same results. Then I thought maybe the settings were off from factory so I started over at 2.5 turns out from bottom. I tried that, only leaning the bottom, with no results. Figured I should ask before ruining something. I was trying to get temps up, even with foil only got to 112, presumably b/c I couldnt get it moving.
__________________
Mitch B
MitchFX is offline   Reply With Quote
Old 05-20-2009, 10:24 AM   #14
Tech Fanatic
 
mfrosty's Avatar
 
Join Date: Jan 2009
Location: Baltimore
Posts: 920
Trader Rating: 14 (89%+)
Default

Don't be scared, lean on the top a little more, if it's dying when your trying to go past say 30-50% throttle your top is too rich. And those low temps also tell me that you're too rich. Also have you been pre-heating your engine. It's always a good idea for the first 1/2-1 gallon, you'll find it'll run better when you first get it started if it's already warm, usually it'll start easier too.
__________________
~TQ Racing~O.S. Engines~AKA~Answer R/C~
http://www.youtube.com/user/frostyone1977
mfrosty is offline   Reply With Quote
Old 05-20-2009, 10:26 AM   #15
Tech Fanatic
 
mfrosty's Avatar
 
Join Date: Jan 2009
Location: Baltimore
Posts: 920
Trader Rating: 14 (89%+)
Default

And when you go to give it throttle are you slowly rolling it on or blipping it? Makes a difference in a rich motor.
__________________
~TQ Racing~O.S. Engines~AKA~Answer R/C~
http://www.youtube.com/user/frostyone1977
mfrosty is offline   Reply With Quote
Reply

Similar Threads
Thread Thread Starter Forum Replies Last Post
Electric 1/8th Scale conversion kits. DJ1978 Electric Off-Road 19923 06-12-2017 05:16 AM
Engine Tuning 101 (General Tuning) Kemorc Onroad Nitro Engine Zone 41 11-19-2007 06:04 PM
RB Concept V12 Circuit 3 Ports 'Rody' acutts Onroad Nitro Engine Zone 9 02-13-2005 01:14 AM



Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are Off



All times are GMT -7. It is currently 04:39 AM.


Powered By: vBulletin v3.9.2.1
Privacy Policy | Terms of Use | Advertise Content © 2001-2011 RCTech.net