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Adjust Airflow Performance FM-150

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ksdflying

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I am looking for someone keen on the AFP FM-150. I have a lycoming io-360-M1B. I would be happy to pay someone to visit and help me adjust my throttle body. Anyone here willing and able or know someone that I can get contact info for. I am located east side of Atlanta area. Again I am happy to pay for this help. Right now it is running very rich, and I need WOT adjusted as I am only getting 2620 RPM. Need tribal wisdom and onsite help!
 
Dan,

I mean no insult, but have you reviewed the installation and setup documentation yet? It can be found here -- https://airflowperformance.com/wp-content/uploads/2018/12/API-Installation-Service-Manual-9003.pdf

Also, a static RPM of 2620 on a fixed pitch prop isn't too far off the mark, it will get faster as the aircraft accelerates. For a constant speed propeller, I would adjust the High RPM limit screw stop >ON THE GOVERNOR< 1 turn per test run until you achieve 2690 ~ 2710.

That said, the good folks at AFP are just up the road from you in Spartanburg SC.
 
I am looking for someone keen on the AFP FM-150. I have a lycoming io-360-M1B. I would be happy to pay someone to visit and help me adjust my throttle body. Anyone here willing and able or know someone that I can get contact info for. I am located east side of Atlanta area. Again I am happy to pay for this help. Right now it is running very rich, and I need WOT adjusted as I am only getting 2620 RPM. Need tribal wisdom and onsite help!

Please define "very rich". Fuel flow/throttle settings/ambient conditions/?. Also need confirmation of prop - fixed or constant speed?
 
Take a trip!

+1 on going to Spartanburg to have AFP balance your FI. The cost is minimal and you will probably spend less than you would spend on injectors you might buy and not use while trying to balance your injectors yourself. I flew three test hops at AFP to get the perfect balance which enabled me to run 50 degrees lean of peak at any altitude. The money I saved in fuel over 2200 hours of flying probably paid for my engine overhaul! Do it right. Let AFP do it.
 
There is no external adjustment for fuel flow at WOT at least on the bendix style and assume the AFP is the same, but not sure. Various things can be tweaked inside the unit to set fuel flow to any given air flow, but that requires a tear down and a specialized shop.

Parts wear and things drift inside of these servos, so I would not expect every servo out there to provide the exact same fuel flow at any given air flow. Flow is controlled by rubber diaphragms and springs, along with needle valving. If full rich is too rich in your installation, you either need to have the unit overhauled or manually manipulate the flow with the red knob.

Ultimately the pilot can easilly control fuel flow at WOT via the red knob. The Bendix on my 320 is way richer than I would like at WOT, so I simply don't use full rich on the red knob. With a bit of experimentation while observing EGTs, you can adjust the red knob for either best power (~100* ROP) or any point rich of that point that suits your performance goals and detonation margin goals when operating at WOT. There is no rule that you must be at full rich, though anything but full rich requires a knowledgeable and attentive pilot. The guys living at 5K+ altitudes are very familiar with this process and are likely to share their best practices for working the red knob at WOT conditions if you ask.



Larry
 
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There is no external adjustment for fuel flow at WOT. Various things can be tweaked inside the unit to set fuel flow to any given air flow, but that requires a tear down and a specialized shop.

Larry

Absolutely not true. Read the manual. It explains how to check and adjust WOT in the field.
 
Absolutely not true. Read the manual. It explains how to check and adjust WOT in the field.

I edited my post to say "on the bendix and have no knowledge of the AFP" apparently after you quoted this. Apparently the AFP provides field replaceable jets for adjusting WOT mixture so my apologies here. No such jet on the Bendix style servos.
 
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Constant Speed (hartzell) prop

Hi all, thank you.
1. Yes I have the AFP install manual and have been studying it.
How do I say this; it is a matter of mentor vs master type of desire here. Yes I think I can adjust this. But in all psychology of things, confidence being just one, for me in all things new here and time is of essence too, everything is way better if I could have a teacher here.
2. I haven't done first flight yet. So injector balancing is in the future via flying over to AFP home, but thank you for that! I WILL make a visit there for their services! Thank you! I want this thing producing the power it should for first flight. But again, at this point in time, for first flight prep, I want someone else by my side teaching and guiding me. Besides this is a two person job anyways.
3. Defining the running RICH bit.....humm, I am not sure how to answer that. Again, why I want to PAY someone to come here and teach. If any one of you want to make some money....come on. But, in attempt to explain this question, the day I ran it the ambient temps where in the 90's, a fairly low humidity day. At the time of the Full Throttle Test, a 15 second test during the 15 minute test at 1500rpm, but at this Full Throttle timing, the CHT's were at average 325, AND it clearly did not like Mixture at Full Rich.....black smoke was biggest indicator, slight roughness. Basically in all my taxiing of this 15 minute test period with rpm at 1500, even especially at idle, it was NOT HAPPY at all at full mixture rich. I even flooded it two times trying to start it due to advancing to full rich.

Hope this helps.
I really want some one onsite. I will pay for it!!!!! Please.
 
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I understand you are looking for someone who can come troubleshoot on-site...

But, the first question Don at Airflow Performance might ask is "what is your full throttle, full rich fuel flow?" Tie it down safely and do a runup to full power.

If you do not have a fuel flow indicator, things related to mixture will be more difficult to solve.

For ground ops, there should be no reason to run it full rich.
 
Adjust the idle mixture first, very unlikely the main jet needs changing.
Small adjustments do a lot, no more than 1/2 turn at most on the rod.
 
Thx Walt. This seems to be the consensus. Per AFP if any adjust at all right now just that, and explicitly only turn the turn buckle on the mixture cable adjust only 1 flat of the hex rod, and only maybe two flats. I talked to two different authorities on this and both blatenly said get the plane in the air and work on breaking that engine in or my fingering around things right now will ruin the good break in of the engine. So I will go through checklists very carefully of both the AFP FM-150 and the Prop govenor. And stop there with the perfection nonsense. I'll do one more fire up to check idle mixture and stop, then fingers crossed it flys. Apparently getting this engine up and flying to 75% power and temps and get the break in process going ASAP is extremely critical on these primitive tractor boxer engines. I was told to get it flying and only after 10 hours do I remotely start thinking about adjusting anything. Fingers crossed I've not screwed anything up. Honestly all I am doing is following Lycoming service instruction and doing due diligence.
I guess I am okay. Nervous but okay.
 
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