Go Back  R/C Tech Forums > General Forums > Nitro Off-Road
Help with my .26 buggy >

Help with my .26 buggy

Help with my .26 buggy

Old 01-04-2014, 11:48 AM
  #1  
Tech Rookie
Thread Starter
 
Join Date: Dec 2013
Posts: 12
Default Help with my .26 buggy

Blew off the dust on my OFNA ULTRA. Been about 5 years since this thing ran. Stored it improperly with the last runs worth of sludge hardened in the motor.

I stripped it down gave a thorough cleaning with alcohol, soaked the one way bearing and carb overnight etc. I had changed the sleeve and piston in this, as well opened up the ports on the sleeve. I remember this thing used to just chug fuel lol.

Now when I run it, I get spurratic high peaks in the RPM while at idle. The throttle is in the idle position and out of nowhere it revs to approx 40% and stalls if I dont kick on the brake.

Could this be simply running too rich? or possibly a bad flow of fuel? Im so rusty at this, and I want to get some time out of this motor before its replacement comes when I have the $$.

Here is a video I shot to give a better idea. Its 6 min and shaky, so just skim it and see if there is anything im missing. There is too much snow on the ground so I still have to take it for a run.. Today I just wanted to get it running and loosened up. May also have a bad seat on one of the crank bearings, heard a bit of a 'whirl' on the first few startups.

+ YouTube Video
ERROR: If you can see this, then YouTube is down or you don't have Flash installed.

Last edited by ModThis; 01-04-2014 at 12:54 PM.
ModThis is offline  
Old 01-04-2014, 02:45 PM
  #2  
Tech Rookie
Thread Starter
 
Join Date: Dec 2013
Posts: 12
Default

No suggestions??? Any ideas??? hmmm...
ModThis is offline  
Old 01-05-2014, 11:03 AM
  #3  
Tech Champion
iTrader: (68)
 
ThePanda's Avatar
 
Join Date: Jul 2013
Location: Michigan
Posts: 7,170
Trader Rating: 68 (100%+)
Default

How is the sealing on the carb? Stuff like needle seals, and the main seal? I'm not a hardcore nitro person, but it might be a carb problem.
ThePanda is offline  
Old 01-05-2014, 11:53 AM
  #4  
Tech Addict
iTrader: (26)
 
jhold87's Avatar
 
Join Date: Oct 2010
Location: Toney Alabama
Posts: 513
Trader Rating: 26 (96%+)
Default

sounds like its way lean. May have a air leak also just from the way it sounds on the vid.
jhold87 is offline  
Old 01-05-2014, 03:16 PM
  #5  
Tech Rookie
Thread Starter
 
Join Date: Dec 2013
Posts: 12
Default

Originally Posted by ThePanda View Post
How is the sealing on the carb? Stuff like needle seals, and the main seal? I'm not a hardcore nitro person, but it might be a carb problem.
Well the whole thing was gummed up, id assume the carb was as well, perhaps not as bad as the block.. I wanted to avoid pulling the carb completely apart just because its been so long and I forget all the tuning procedures, but that may be the route.

Originally Posted by jhold87 View Post
sounds like its way lean. May have a air leak also just from the way it sounds on the vid.
I stripped the motor down, the seals were a bit gunked up, but after some solvent and cleaning the seals appeared to be good. I used heavy oil while reassembling prior to the first start which is when it started acting up.

The first time the RPM's took off I thought the tank was empty, sounded just the same as air in the line, but that was not the case

Maybe this just needs a few high speed runs, though will have to wait until this snow clears up a bit. In the mean time I am going to open up the carb and see if there isnt some sort of blockage occurring at idle.

Regarding a lean mix, I had it set very rich to the point that raw fuel was coming out of the exhaust. It sat for so long I didnt want to chance any lean runs..
ModThis is offline  

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


Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service - Do Not Sell My Personal Information

Copyright 2018 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.