VansAirForceForums  
Home > VansAirForceForums

- POSTING RULES
- Donate yearly (please).
- Advertise in here!

- Today's Posts | Insert Pics

  #1  
Old 05-20-2016, 11:22 AM
Carl Froehlich's Avatar
Carl Froehlich Carl Froehlich is offline
 
Join Date: Dec 2007
Location: Dogwood Airpark (VA42)
Posts: 2,596
Default pMags on the IO-390

Just installed a dual pMag set up on an RV-14 getting close to engine start. For those of you thinking of this, the IO-390 uses long reach plugs. eMag sells long reach plug adapters so you can use auto plugs. The correct plug for this application is the Denso IKH27. Amazon has them: http://www.amazon.com/Denso-Iridium-.../dp/B000M6URAA

BTW - if anyone wants a set of new IO-390 mags, harnesses and plugs, let me know.

Carl
Reply With Quote
  #2  
Old 05-20-2016, 11:38 AM
n982sx n982sx is offline
 
Join Date: Apr 2010
Location: Chicago, IL
Posts: 356
Default

Carl,

I'm thinking of doing at least one but maybe both. When doing both, does the left one have the impulse coupler, and do you need to buy a replacement gear?
__________________
Bob Meyers

Built and Flying RV-14A N626KM SN 140093 http://n626km.com
Built and Flying Sonex N982SX http://n982sx.com
Reply With Quote
  #3  
Old 05-20-2016, 12:00 PM
Mike H Mike H is offline
 
Join Date: May 2014
Location: Savannah
Posts: 806
Default

The IO-390 does not use an impulse coupled mag.
__________________
Mike Hammond
A&P IA PPL ASEL
RV-14A kit S/N 140170
Reply With Quote
  #4  
Old 05-20-2016, 12:21 PM
Carl Froehlich's Avatar
Carl Froehlich Carl Froehlich is offline
 
Join Date: Dec 2007
Location: Dogwood Airpark (VA42)
Posts: 2,596
Default

Quote:
Originally Posted by n982sx View Post
Carl,

I'm thinking of doing at least one but maybe both. When doing both, does the left one have the impulse coupler, and do you need to buy a replacement gear?
You do use the gear off the right mag. You cannot use the gear that is on the left mag (the one with the impulse coupler). eMag will sell (and install if you like) a gear for you for the left side. eMag buys standard Lycoming mag gears in bulk and sells them to customers at a discount.

Remove the left mag and then remove the mag impulse coupler spacer. As you no longer have the mag impulse coupler spacer on the left side, you may wish to replace the mag engine studs with shorter ones to match what is on the right side.

Carl
Reply With Quote
  #5  
Old 05-20-2016, 12:38 PM
rvbuilder2002's Avatar
rvbuilder2002 rvbuilder2002 is offline
 
Join Date: Jul 2005
Location: Hubbard Oregon
Posts: 9,035
Default

Quote:
Originally Posted by Mike H View Post
The IO-390 does not use an impulse coupled mag.
The one in the prototype does and it starts just fine with just the left mag being an Impulse.
__________________
Opinions, information and comments are my own unless stated otherwise. They do not necessarily represent the direction/opinions of my employer.

Scott McDaniels
Van's Aircraft Engineering Prototype Shop Manager
Hubbard, Oregon
RV-6A (aka "Junkyard Special ")
Reply With Quote
  #6  
Old 05-20-2016, 01:03 PM
Mike H Mike H is offline
 
Join Date: May 2014
Location: Savannah
Posts: 806
Default

Quote:
Originally Posted by rvbuilder2002 View Post
The one in the prototype does and it starts just fine with just the left mag being an Impulse.
Hmm...I guess I am having a silly brain moment. I thought mine had a left mag that was set up for a Slick Start. I will have to open the box and look again. I guess that is what I get for thinking sometimes...
__________________
Mike Hammond
A&P IA PPL ASEL
RV-14A kit S/N 140170
Reply With Quote
  #7  
Old 05-20-2016, 05:13 PM
APACHE 56 APACHE 56 is offline
 
Join Date: Jan 2008
Location: MERRITT ISLAND, FL
Posts: 360
Default NGK plug

Quote:
Originally Posted by The correct plug for this application is the Denso IKH27. Amazon has them: [url
http://www.amazon.com/Denso-Iridium-Spark-Plug-IKH27/dp/B000M6URAA[/url]

Carl
I used the Denso for a few years on my IO 390 but found this alternative: NGK LZFR5C-11 Spark Plug #NGK-92174

I don't know that fine wire is really necessary with an electronic ignition. The NGK's are much less expensive and work just as well.

Don
__________________
Don Stiver
RV8 "Little Pill" N6371S, Merritt Island, Fl.
BPE IO-390, Dual P-mag, MT 3-blade, AFP system
Steen Skybolt: Sold
Reply With Quote
  #8  
Old 05-20-2016, 07:20 PM
N941WR's Avatar
N941WR N941WR is offline
 
Join Date: Jan 2005
Location: SC
Posts: 12,887
Default

What is the standard timing on the IO-390 engine?

I ask because you want to make sure the P-mags are configured correctly, which can be done with either the EICAD program available on the Emag website or with our EICommander.

The P-mag w/o the jumper in is set to a little over 30 degrees, which is great if you are flying behind a Continental A65 but not so good for a Lycoming O-320 or larger.

With the jumper in, they fire at 26 degrees before TDC, which works for most standard parallel engines. However, if you have high compression pistons, you might want to think about moving it down a few degrees and if you have an angle valve engine, it should be set to 20 degrees.

If you are buying new P-mags, they will have firmware version 40 (or higher) and should be set to TDC when timing them. There is no need to clock them as some have done with light props and earlier firmware versions.

PS. I will be demonstrating the P-mags and the EICommander at OSH again this summer. Watch the forums for the date, time, and location.
__________________
Bill R.
RV-9 (Yes, it's a dragon tail)
O-360 w/ dual P-mags
Build the plane you want, not the plane others want you to build!
SC86 - Easley, SC
www.repucci.com/bill/baf.html

Last edited by N941WR : 05-20-2016 at 07:22 PM.
Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT -6. The time now is 01:52 AM.


The VAFForums come to you courtesy Delta Romeo, LLC. By viewing and participating in them you agree to build your plane using standardized methods and practices and to fly it safely and in accordance with the laws governing the country you are located in.