What's new
Van's Air Force

Don't miss anything! Register now for full access to the definitive RV support community.

IO-540

N

N-336TX

I'm New Here
Howdy, I've got a few questions vis-a-vis engines for a -10.

Van's recommends either a 235hp or 260hp version of the IO-540

I have heard the 235hp version uses low compression pistons and is thus more friendly to automotive gas. True?

With its designation "IO" does that mean it's fuel injected only? Is there a carburetor version of this available? Pros/cons

Does the injected version require battery to run or is there a magneto set-up for that?

Is the model number for the 235hp version IO-540-B4B5?

Sorry for the newbie questions. My familiarity with engines is 1960s Ford Mustangs (and my Hyundai). I'm looking for a set-up that will be fairly easy to maintain myself without the need for a computer or too much special equipment. I like getting my hands dirty and using my mechanical mind to make stuff purr.

Thanks in advance!
 
The leading I in the engine designation is what signifies it is injected. A carbed engine would be a O540. The O means opposed bty.

The engine will run without a battery after starting, unless it has an electronic ignition system. The battery is for the starter, and the boost pump.
 
Injection + Magnetos?

Mike S said:
The engine will run without a battery after starting, unless it has an electronic ignition system. The battery is for the starter, and the boost pump.
Click to expand...

So even the Fuel Injected versions have magnetos?

Sorry for the dumb questions, I'm just getting my pitch together to sell my wife on the idea of building an RV-10 ;)
 
Yes, the fuel injection is completely mechanical and not tied in any way to the ignition system (unlike your Hyundai).
 
N-336TX said:
Howdy, I've got a few questions vis-a-vis engines for a -10.

Van's recommends either a 235hp or 260hp version of the IO-540

I have heard the 235hp version uses low compression pistons and is thus more friendly to automotive gas. True?

Yes

With its designation "IO" does that mean it's fuel injected only? Is there a carburetor version of this available? Pros/cons

Both carbureted and injected are available.

Does the injected version require battery to run or is there a magneto set-up for that?

No battery required for either engine to run unless running an electronic ignition.

Is the model number for the 235hp version IO-540-B4B5?

The TCDS (see link http://www.tvbf.org/docs/lycoming-o-540.pdf) shows 8 model numbers with 235 hp, including the O-540-B4B5

Sorry for the newbie questions. My familiarity with engines is 1960s Ford Mustangs (and my Hyundai). I'm looking for a set-up that will be fairly easy to maintain myself without the need for a computer or too much special equipment. I like getting my hands dirty and using my mechanical mind to make stuff purr.

Thanks in advance!
Click to expand...

Good luck with your quest.
 
N-336TX said:
So even the Fuel Injected versions have magnetos?
Click to expand...

Magnetos are the standard setup, but there are alternatives available.

Some alternatives are magneto based, like G3 ignitions offers, or the Slick Lasar system, and there are the full electronic units like EFII and Lightspeed etc.

The basic way the engine will come from Lycoming is with mags, unless specified differently.
 
If you are building a -10, and investing in an expensive machine, there is a simple answer.

IO540D4A5 260HP.

Like most things Vans recommend, it is for a good reason. ;)

Save the agonising decisions for things like paint scheme, interior colours and trim, avionics, your rego number.
 
Engine

Vans also recommends the 235hp version. At double the cost, I think I'd like to run Automotive Gas. (sanz ethanol)

Not to mention, it looks like 100LL will be going away some time if the EPA has its way.
 
N-336TX said:
Vans also recommends the 235hp version. At double the cost, I think I'd like to run Automotive Gas. (sanz ethanol)

Not to mention, it looks like 100LL will be going away some time if the EPA has its way.
Click to expand...

I don't believe that is their current thought. To my knowledge, there is only one of them flying.
 
N-336TX said:
Vans also recommends the 235hp version. At double the cost, I think I'd like to run Automotive Gas. (sanz ethanol)

Not to mention, it looks like 100LL will be going away some time if the EPA has its way.
Click to expand...

My engine is the IO-540 V4A5, 260 hp with low compression pistons. At the Lycoming tear down seminar held at Oshkosh a few years ago, I point blank asked the Lycoming representative if I could run mogas in it and he stated absolutely yes,,,and it would be very happy doing so.
 
Ranging compression/gas

aerhed said:
The 260's have 8.5:1 compression... They love 91UL.
Click to expand...

I think the 235hp version has 7.2:1 compression, so it might like 89 octane ethanol free (and that's under $3 a gallon right now, some places 100LL is $6!!!)
 
There are several of us running a 235 hp engines

I built an RV10 and put an 0-540 J3C5D in my airplane. I got a very good deal on a low time engine and prop. My engine is limited to 2400 RPM and is 40 Lbs lighter than the standard engine Vans sells.

I am about 5 knots slower at cruise and I can get about 1200 fpm climb out of it on a cool day at about 100 knots.

5 knots in a 10 hour day of flying is 50 nautical miles. At 150 knots that is about 20 minutes.

I was willing to save $25,000 at the expense of a few extra minutes flying.
Yes, I am sure when I go to sell it I won't get as much out of it, but selling is likely to be a long way off for us.

I am very happy with my setup.



rleffler said:
I don't believe that is their current thought. To my knowledge, there is only one of them flying.
Click to expand...
 
You must log in or register to reply here.
Back
Top