Model Forum / Radio Controlled / Land Models / January 2007

One of two things:

1) Small hole somewhere in the fuel tubing or fuel tank
2) Engine overheating and boiling fuel out of carb due to a lean tune

I'd wager it's number 2 due to the fact that the bubbling is accompanied by
the engine dying.  Richen up the LSN and HSN one full turn each and see if
it gets any better.

Doc

Hi there.
As Doc said, ot is probably a lean mixture, it happenned in my car. It comes
improperly adjusted from factory and you have to keep mixture way rich to
avoid over-heating the engine.
I'd advise you to get an onboard thermometer to keep an eye on runnig
temperature.

HSN (High Speed Needle) is the mais adjuster for the carb and is placed on
left side of engine, where the fuel hose attachs the carburator (part number
42 if you have the engine schematics).

LSN (Low Speed Needle) adjusts the mixture at low throtle use and is placed
in the arm that is activated by the servo (part 45 oh the same schematic).

To richen mixture you have to back out the adjuster (turning it
counter-clockwise) and to lean mixture you have to scren in the adjuster
(turning it clockwise). Usually this adjustments are made at 1/8 of turn at
a time.

If you do a search in this group and some 'net forums you can find a lot of
info about tuning your engine, as the included manuals are garbage.

By the way, prepare you to get a lot of spare parts, as these chinese
imitantions of an r/c car seem to desintegrate themselfes.

Hope it helps you out somehow.

Rodolfo Barros
louco_pt@hotmail.com

----- Original Message -----
From: "da_linuxguru" <dhavaljdesai@gmail.com>
Newsgroups: rec.models.rc.land
Sent: Tuesday, January 23, 2007 1:47 PM
Subject: Air Bubble in fuel linke