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IO-360 Fuel Injection

bryannortje

Well Known Member
Hi Guys

I wonder if someone can help. I have an IO-360 Parallel valve 180Hp w/CS prop. At WOT full rich I only get 13.8-14 gph fuel flow which seems low based on some reading I have done.

What should I expect to see and whom would you guys recommend to send my fuel servo in to for a IRAN check and service. I am based in NC.

Thanks
Bryan
 
Hi Bryan,

I typically see 16.5-17.0 GPH on take-off with the same engine/prop you describe. Your flow does sound low. Is your fuel flow sensor well calibrated? I assume you are seeing that flow at a low altitude (<1500 feet)?

I have an Airflow Performance injection system. I have had it serviced only once by Don Rivera at Airflow Performance. Very good service from Don.

Good luck,

Dean
 
Fuel Flow

Hi Dean

Fuel flow in gph reading is within one gallon over 4 hrs of flying. Our field elevation is 740ft.

Thanks
Bryan
 
I would suggest you call Airflow Performance. They are located in Spartanburg, SC. Your fuel flow sounds low, but you should do some EGT tests before sending in the servo. Don at Airflow Performance can help you with what to look for.
 
Brian---youre at Gold Hil-----Kahuna and Ron Schreck are both there and could possibly help.
Don Rivera is an easy flight to Spartanburg---

Tom
 
Check the simple stuff first. Make sure you?re hitting the stops for throttle and mixture.
 
EGT

What is your EGT? It seems like if you were running lean (not enough flow for the air) your EGT would be reading high, otherwise plenty of flow for the air mixture.
 
photo's

zLmuuR


https://www.flickr.com/photos/161051606@N06/shares/36531L
 
If the one pic is wide open and full rich, 1400 EGT does seem high like the mixture is a little lean (not enough fuel flow). Mine is down around 1250 full rich and wide open.
 
info

So, how I see it is that I should have a guide based on the engine, what the typical fuel flow should be at WOT (2700 rpm) full rich. The EGT's are a reference number rather than a target temp as I have yet to check if they are mounted exactly the same distance from ?? or if there is actually a specified or recommended distance from exhaust mounting flange.

Thanks
Bryan
 
Download Lycomings Power Chart. You can readily see that something isn?t right and you are way too lean on a full rich full power takeoff. Things seem to match up better in your cruise settings.
Download the installation manual for your EFIS. It should give you the recommended distance for the EGT probes to the flange.
Unless they where grossly out of spec, your EGTs are high on take off. You should see EGT?s around 400degF below max EGT.
You?re way to lean on take off. Now time to figure out why.
Again, I would check to make sure your mixture is indeed hitting the stop.
If it is, check your injectors and seen what size they are. Good info to have at hand before you call Precision or Don.
 
One note - his MAP was only 27.0". I don't have a chart handy, but I often see 29" at takeoff. Is that two inches enough to drop Fuel Flow that much?
 
One note - his MAP was only 27.0". I don't have a chart handy, but I often see 29" at takeoff. Is that two inches enough to drop Fuel Flow that much?

No.

I am about 1400 ft higher in Asheville than the OP so my MPs are down but the fuel flow is still a lot higher than shown and my EGTs are in the 1200s.
In regards to EGT probe position, I think it would be unusual for EGTs to read higher if the probes were farther away from the cylinder. Mine are in the positions described by GRT (the monitor in the OPs images), which are pretty close to the pipe flange. 1400 is way too high for takeoff.

That motor is too lean on takeoff, plain and simple.

Is there any motor history? Is it a Lycoming through Vans? I know my documents from the Vans/Lycoming purchase showed the test run and critical values such as we are discussing.

I'd take a really hard look at the mixture lever travel on the injector servo and make sure it is hitting the stops. With the custom belcrank for the RSA-5, I found it a bit fiddly to get everything hitting the stops and operating smoothly throughout the range.
 
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Just for easy reference, I have an app on my phone called the IO-360 Power Calculator (available for both iOS and Android) for the 200 HP angle valve engines.

You just set the percent power desired, altitude and OAT and you get manifold pressure and the associated fuel flow. There are options for both best power and best economy. It is dirt simple and fast to use, although your particular installation might be a bit off the numbers depending on intake, compression ratio, etc.

Example output- @1500' and 54?F, max power available is 90% at 2700 RPM and 14.5 gph (or 2600 @14.4 gph). In order to get 95% at 1500', you have to be below 52?F, where you can get it 2700 RPM and 15.1 GPH.

I find this to be a good guideline for operations.
Andy
 
App is gone! :(

Well, ****. :mad: After someone pinged me that they couldn't find the app, I went to the Air Dave web site and found that it has been removed from both app stores. There are some explanatory notes why at the bottom of this web page.
If anyone knows how it might be possible to "transfer" an app to another user, please advise. Mine is Android, BTW.
Sorry,
Andy
 
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