[NSRCA-discussion] OS 140RX Need Help

Sun Aug 9 08:41:31 AKDT 2009

I pushed some Denatured Alcohol through the pump and it seemed to clear that
up quite a bit...If I let it sit it will drip a little now and not at all at
idle. So that seems to be under control...

Now it idles very well and I can adjust top end. I'm getting about 7,900 on
a 4 bladed prop 15.5x12 APC w/ PM Mean Green (15% w/ 18% all synthetic oil).

However, once it idles for any length of time or even 1/2 throttle, it will
bog down and quite as soon as I start to advance the throttle. If I pinch
the fuel tube it will pick up and run. If I go high then low and back to
high throttle without too much delay it transitions well. If I'm at idle for
about the same time as stall turn down line (2 or 3 seconds) it will bog
down...

This is what I'm assuming everyone has keyed in on as the symptom of a main
<http://www.rcuniverse.com/buynow/keywordclick.cfm?bid_id=6534> bearing
going bad...

Off to surgery...now I get to see what the inside of a 140RX looks like...

Again, Thanks for all the help....

  _____  

From: nsrca-discussion-bounces at lists.nsrca.org
[mailto:nsrca-discussion-bounces at lists.nsrca.org] On Behalf Of Lisa n Larry
Sent: Sunday, August 09, 2009 9:15 AM
To: pnahobbies at sbcglobal.net; 'General pattern discussion'
Subject: Re: [NSRCA-discussion] OS 140RX Need Help

I have the stock needle..

My main spare bearing is a Boca Bearing.P/N 6904Z and it is either shielded
or sealed.

There appears to be no detectable play in the main bearing currently
installed in the motor.

My strategy is to flush the pump first and see how it responds.If no go,
then replace the main bearing.

Thanks for all the help, I will keep you posted.Hopefully we will get a few
practice flights in yet today.

Larry

  _____  

From: nsrca-discussion-bounces at lists.nsrca.org
[mailto:nsrca-discussion-bounces at lists.nsrca.org] On Behalf Of Ihncheol Park
Sent: Sunday, August 09, 2009 3:46 AM
To: 'General pattern discussion'
Subject: Re: [NSRCA-discussion] OS 140RX Need Help

losmg7025.jpg

61FX needle is longer than the one on 70A.

losmg7052.jpg

Stock needle for 70A carb.

From: nsrca-discussion-bounces at lists.nsrca.org
[mailto:nsrca-discussion-bounces at lists.nsrca.org] On Behalf Of Lisa n Larry
Sent: Saturday, August 08, 2009 10:37 PM
To: 'General pattern discussion'
Subject: Re: [NSRCA-discussion] OS 140RX Need Help

Dennis, as always you are right on the money.

I have not touched the pump or anything else other than the HS needle.I
believe it is either an OS # 8 or a "F".I don't have a 61 FX.

Always coming back to the main bearing.There seems to be a trend here.

I haven't flown a contest in over two years.Looking to get back in the
saddle.I appreciate all the help..

Larry

PS, Dennis you just want to see my caller LOL.

  _____  

From: nsrca-discussion-bounces at lists.nsrca.org
[mailto:nsrca-discussion-bounces at lists.nsrca.org] On Behalf Of Dennis Bodary
Sent: Saturday, August 08, 2009 10:31 PM
To: General pattern discussion
Subject: Re: [NSRCA-discussion] OS 140RX Need Help

I am assuming this engine has sat for awhile. try injecting some straight
methanol into the pump inlet line just in case the oil in the pump is
congealed. denatured alchohol will work fine for this. 

Do not take the pump off the backplate thinking you can clean it out. Bad
stuff will happen as the backplate is part of the pump you may or may not
even be able to put it back together. 

Also try a OS F plug or the YS 4 stroke plug. never had any luck with the A5
plug that came with it. 

Another thought is check the needle valve against a OS61FX if the needle
valve looks the same you are okay. If the needle taper part is different try
the 61FX needle valve. It may already be in the engine as it comes with the
engine as a optional part. 

If all else fails try replacing the rear bearing. 

--- On Sat, 8/8/09, Lisa n Larry <lld613 at psci.net> wrote:

From: Lisa n Larry <lld613 at psci.net>
Subject: [NSRCA-discussion] OS 140RX Need Help
To: "'General pattern discussion'" <nsrca-discussion at lists.nsrca.org>
Date: Saturday, August 8, 2009, 9:56 PM

I'm trying to get a plane going to make the Quincy , OH contest next
weekend.

When running at idle or the engine isn't running, fuel leaks out of the
carb. I can get it started, but loads up in about ten seconds and bogs down
and dies when increasing the throttle.

If I pinch the fuel line, it leans out and recovers. As long as I stay near
full throttle it's fine.When at half throttle and lower it will bog down..

HS needle is at about 1-3/4 out leaned from about 2 turns out. I don't know
the pump settings.

This is a used engine already installed in a plane.

Is it just a matter of the pump pressure being too high or do I have other
problems to deal with.???

Larry Diamond

NSRCA 3083

-----Inline Attachment Follows-----

_______________________________________________
NSRCA-discussion mailing list

<http://us.mc517.mail.yahoo.com/mc/compose?to=NSRCA-discussion@lists.nsrca.o
rg> NSRCA-discussion at lists.nsrca.org
 <http://lists.nsrca.org/mailman/listinfo/nsrca-discussion>
http://lists.nsrca.org/mailman/listinfo/nsrca-discussion

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.nsrca.org/pipermail/nsrca-discussion/attachments/20090809/7037aec7/attachment.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: image/jpeg
Size: 17765 bytes
Desc: not available
URL: <http://lists.nsrca.org/pipermail/nsrca-discussion/attachments/20090809/7037aec7/attachment.jpe>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: image/jpeg
Size: 19663 bytes
Desc: not available
URL: <http://lists.nsrca.org/pipermail/nsrca-discussion/attachments/20090809/7037aec7/attachment-0001.jpe>