IO-240B idle settings

[Tri4874]

I need to adjust the idle setting on an IO-240B. Does anyone have any literature, maintenance manual or installation info that may help...thx

[airlina]

I have the IO-240B on my Series 5 , and guidance from Continental in SID98-10 used to be an idle RPM setting of 850 RPM preferred which I found was too high for my Kitfox if you want to land at some point. This SID is the bulletin that details the entire fuel system setup that should be done regularly. Typically I do the fuel system setup every 100 hours or if I notice any anomolies that require it done. SID 98-10 is now superceeded by SID 97-3E (you can google this and find it in PDF form ) and Continental says in this bulletin to set idle RPM to aircraft manufacturer specs. Since I am the aircraft manufacturer, I set my idle RPM to no more than 700 RPM , and with the addition of one PMag electronic ignition a few years back, I found that 600 RPM was doable after getting rid of one traditional mag. The Pmag does a much better job of firing at low RPM which a traditional mag can't handle. Hope this helps . Bruce N199CL

[PapuaPilot]

I think the best source of data for this engine is the Continental M-0 "Standard Practice Maintenance Manual'. This covers nearly everything on every Continental engine, including the procedures and settings for the IO-240 engine. The latest revision was in February this year.

I should try a lower idle RPM too, mine is around 850.

I confirm my full throttle static RPM metered fuel pressure at every condition inspection (it's displayed on the G3X engine screen) and have not needed to adjust anything in the last couple years.

To adjust the fuel system you need to hook up an accurate and calibrated pressure gauge that reads to a 1/10 PSI.

[n85ae]

All of the previous comment are close, but no cigar ...

The latest greatest is SID 97-3G and if you need to adjust idle, you really should do a fuel injection
pressure run through.

Here's a link to a copy of the doc:

https://www.twincessna.org/pdf/SID97-3G.pdf

Jeff

[n85ae]

Actually if you have never done an IO-240B Fuel Pressure setup, while it's not super complicated
it would be a good idea to get somebody who know's how and has the gauges, etc. Most any shop
that has serviced Continentals will know how to do it.

It's a bit tedious, because you need to go back and forth between metered, unmetered, and then set
the idle mixture, and throttle stop. Each adjustment tends to affect the others, so it takes 2-3 iterations
to get it right ... I've replace my fuel pump twice, and while I'm getting pretty good at it, it's still not
the most fun thing to do.

Jeff

[PapuaPilot]

All of the previous comment are close, but no cigar ...

The latest greatest is SID 97-3G and if you need to adjust idle, you really should do a fuel injection
pressure run through.

I beg to differ Jeff. While SID 97-3G works for the job in question this bulletin no longer exists. It was one of 20+ bulletins that were incorporated into the M-0 manual. Any updates to these procedures will end up in chapter 6 of the M-0 manual.
www.continental.aero/support/maintenance-manuals.aspx (http://www.continental.aero/support/maintenance-manuals.aspx)

Unfortunately this manual needs to be purchased. I don't see any differences for the IO-240 from SID97-3G, go ahead and use this document.

[n85ae]

Thanks Phil

Interesting, I just downloaded the 97-3G last fall from Continental when I replaced my Pump. Good to know about
this manual. I see the website is password protected, any chance you could let me grab a copy of the M-O manual
from you in pdf?

Jeff




I beg to differ Jeff. While SID 97-3G works for the job in question this bulletin no longer exists. It was one of 20+ bulletins that were incorporated into the M-0 manual. Any updates to these procedures will end up in chapter 6 of the M-0 manual.
www.continental.aero/support/maintenance-manuals.aspx (http://www.continental.aero/support/maintenance-manuals.aspx)

Unfortunately this manual needs to be purchased. I don't see any differences for the IO-240 from SID97-3G, go ahead and use this document.

[Tri4874]

Thanks to all the replies..👍