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<DIV>Ed,</DIV>
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<DIV>Long shot - but double check throttle servo mount/linkage, and mounting of engine, softmount, nosering, pipe, etc - any of that stuff gets loose, funny things can happen.</DIV>
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<DIV>Anderson should have fuel for you.</DIV>
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<DIV>Dave</DIV>
<DIV> </DIV>
<BLOCKQUOTE style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #1010ff 2px solid">-------------- Original message -------------- <BR>From: "Ed Miller" <edbon85@charter.net> <BR><BR>> Have an OS 140RX that has developed a rough and inconsistent idle. Engine <BR>> runs perfectly except for idle. It has a Mintor head with either an OS F or <BR>> K&B 1L in center plug and an OS A5 in the angled plug position, a Perf Spec <BR>> AAC piston/liner assembly and a Boca sealed SS rear bearing. I have the head <BR>> mounted with angled plug towards the front or carb side of engine. Fuel is <BR>> S&W 20 nitro, 16 synthetic and 2 castor. Engine has 7 gallons of fuel run <BR>> through it. Prop is an APC 15.75 x 11 3 blade by Dave Lockhart. The lowest <BR>> I can get the idle before it quits is 1900 ~ 2000 rpm and it is rough, <BR>> sounds like it is firing every other revolution. Idle mixture screw is <BR>> working, I can richen idle to point wher
e engine will barely transition from <BR>> being rich and I can lean mixture so the transition is fine but engine slows <BR>> at idle like it is too rich. While it is slowing with either the idle <BR>> mixture screw lean or rich, engine is rough, again like it often fires every <BR>> other revolution at times. I used to be able to reliably idle this engine at <BR>> 1300 rpm. I have a second OS 140RX set up exactly the same except it doesn't <BR>> have the AAC piston/liner and it runs/idles perfectly. Tried cleaning the <BR>> carb/spray bar with no change. I once had a Super Tiger that exhibited <BR>> similar characteristics due to a worn out con rod. Is it possible the con <BR>> rod on this OS could cause this issue ?? Any suggestions will be greatly <BR>> appreciated. <BR>> Ed M. <BR>> _______________________________________________ <BR>> NSRCA-discussion mailing list <BR>> NSRCA-discussion@lists.nsrca.org <BR>> http://lists.nsrca.org/m
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