Hangar Flying

Hangar Flying => Hangar Flying => Topic started by: mnmills on January 24, 2011, 12:56:32 AM

Title: Manifold Pressure line for EIS, O-235
Post by: mnmills on January 24, 2011, 12:56:32 AM

I just bought the Electroair electronic ignition system.  I have an O-235 with a Marvel Schebler MA-3A carbuerator.  I hear that you can pick up the manifold pressure line off of the carb, but Im not sure where and what fitting I need.  Anyone done this before or have another idea where to pick up the pressure line?  I thought about tapping a nipple into the intake manifold on cylinder 3 or 4 but I dont want to disrupt the fuel flow to a cylinder with the threaded nipple.

Thanks,
Mike

Title: Re: Manifold Pressure line for EIS, O-235
Post by: Bruce Hughes on January 24, 2011, 01:35:50 PM

Hi Mike

Do you have an owner's manual?  I think you will find a reference to 2
ports on each cylinder.   I am using a O-320 and I think the O-235 is the
same for ports.  Look them over.

I use one port for MP (on cylinder #3) and one (on every cylinder) for
priming.   BTW: Use VERY good quality FLEXIBLE hoses for those lines.
Do NOT run the hoses directly from port to firewall; they need more support
than that.  And use the correct union fittings with silver soldier on the ports.
I have stainless steel braded teflon lined hoses for both MP and priming
(different sizes so they cannot be accidentally reversed).

Bruce Hughes   :)

Title: Re: Manifold Pressure line for EIS, O-235
Post by: mnmills on January 24, 2011, 10:53:31 PM

Bruce,

Do you mean a O-235 manual?  I dont have one but Ill go search for one online.

Mike

Title: Re: Manifold Pressure line for EIS, O-235
Post by: mnmills on January 24, 2011, 11:47:18 PM

Just read the O-235 manual, only shows one but Ill check in the morning to see if there are two.

Title: Re: Manifold Pressure line for EIS, O-235
Post by: Bruce Hughes on January 25, 2011, 05:07:26 AM

Hi.   1 port per cylinder will do because you do not have to prime all
4 cylinders.   I think you will find 2 per cylinder.   Look very carefully
at the cylinders all around the end of the cylinder near the spark plug,
and valves.   There will be threaded plugs in the ports.

I am away from home just now or I could look in my owner's manual.
Also, the owner's manual may not show it; a rebuild manual is more
complete.

Bruce   :)

Title: Re: Manifold Pressure line for EIS, O-235
Post by: mnmills on January 26, 2011, 08:07:04 PM

Only one per cylinder, cut the primer line.  Im good now...thanks!

Title: Re: Manifold Pressure line for EIS, O-235
Post by: Bruce Hughes on January 26, 2011, 08:21:33 PM

OK but you should ask an engine guy; I think you have 2 ports per cylinder.
The O320E2A does.

Bruce Hughes    :)