Electronic Fuel Injection

[Wingsoverafrica]

Managed to get a Welder to the aircraft today and tagged the injector bosses in place, carried on with some more wiring. Finalized the return line to the hopper tank.

Tomorrow,,,,flight in a cessna 170 then back to work...Wiring, cut panel,

Black Knob on the panel is for setup and fine tuning, anti- clock lean, clockwise fully rich.....centre 0 as per last setup.

[Wingsoverafrica]

So today decided to fit the new alternator. This allows for 45 amps constant to be available. This was planned anyway as the one fuel Injection pump uses 20 amps to start and runs at about 5 amps constant. ECO uses 1 Amp and though forth. Current charge system only gives out 16 amps on a good day but nothing while idle, so one can imagine what would happen to your batteries by the time you airborne. Alternator has a build in regulator so spend some time removing the old regulator and all redundant wiring. Also decided to loosen all the covering and go through the wiring in the engine bay with a fine tooth comb. Still need to change the earth buzz,,,mondays problems.

Installed the airbox cover and Scat hose to check for fit and clearance between the scat hose and throttle arm on the throttle body , very little clearance but nothing is touching.

Anyway I'm impressed with the quality , all part CNC machine from Billet aluminum nice and light weight. Alternator belt is very thick , can't see this to be an issue, recommended 100 hr inspection on the belt. When removing everything its important to install the left coil before you and the adapter plate , learnt the hard way had to remove everything and start again. Also adjust the coil gap....

[ZuluBen]

I like that alternator

[Wingsoverafrica]

I like that alternator

I like is as well ... . It solves a whole bunch of issues.

[jetjr]

Both Rotec and Camit in Oz do them now, I think Camit can leave original in place too as backup?

[Wingsoverafrica]

Both Rotec and Camit in Oz do them now, I think Camit can leave original in place too as backup?

I would prefer removing the old unit. Discovered yesterday that its actually quite heavy, the magnet ring, bracket and alternator / generator thing weight actually nearly offsets the new unit. Besides why leave it in, you never had a backup before. More wiring more to worry about. How often does you vehicle alternator fail??

[checkride]

Having dual alternator in a jabi is just over the top. you can leave dual alternator for proper IFR aircraft.

[jetjr]

All true, not suggesting its agood feature but i have had plenty of automotive altenators die and belts break over years

[T4flyer]

Just a question. If the original alternator only supplies about 16 amps how much more HP will the new 45 amp alternator draw over the original one?

Cheers, Don.

[Wingsoverafrica]

All true, not suggesting its agood feature but i have had plenty of automotive altenators die and belts break over years

That's why you pre-flight. I have never had a alternator or belt break been driving for 35 yrs, you must be bad luck. I Don't think you can compare the usage of an alternator on a vehicle to one on an aircraft. i think the unot on a vehicle is subject to much more abuse/ use than that on an aircraft. Our max RPM is 3300 pretty constant were that on an vehicle would be anything from 500 rpm to 7000 depending if you a lunatic or not,your driving style etc very different wear and tear.

Our maintenance standards are a lot more OTT compared to that of a vehicle .

[Wingsoverafrica]

Today did the final fit of the LCD programmer for the EFI. Repositioned the RDAC for easy access and maintenance and continued removing redundant wiring. Looks a mess for now but watch this spot......

Don don't know how to answer your HP question.

Anyway tomorrow need to have a new Battery box constructed . Intake manifolds with Injectors should be back from the welders. Hopefully we can start finalizing things....

[Wingsoverafrica]

Having dual alternator in a jabi is just over the top. you can leave dual alternator for proper IFR aircraft.

If we loose alternator we have Dual batteries , should be good for at least 30 min with min avionics and one pump running. We running dual battery's below are the specifications.

Aerovoltz 12 Cell Lithium Battery
12V-20 PbEq/AH - 410 CCA
112MM (L) x 86MM (W) x 103MM (H)
1100 grams (2.5 lb)
Amperage: 20 A/H @ 10 A/H Rating
Pulse Cranking Amps: 410 amps
Operating Environment:
18°C (0°F) to 60°C (140°F)

[scsirob]

Just a question. If the original alternator only supplies about 16 amps how much more HP will the new 45 amp alternator draw over the original one?
Cheers, Don.

1HP = 745 Watt. When you draw 45A then that would mean 45A x 13.8V = 621 Watt. That's about equal to 0.8HP. Add a little bit for friction losses (belt, mechanics) and you lose 1HP.

The alternator only loads the engine for as much as you demand. If your system draws 20A then you are closer to 0.4HP.

[scsirob]

Having dual alternator in a jabi is just over the top. you can leave dual alternator for proper IFR aircraft.

It's a trade-off between weight and redundancy. Electronic ignition introduces a single point of failure. It doesn't work without electrical power. Leaving the original alternator in place with just the regulator and a small battery will mean continuing your planned flight if you lose the main alternator, main battery, or the wiring in between. Having a spare source of electricity means continued flight over that long stretch of open water. No 30 (hopefully) minute battery life to worry about.

[checkride]

I understand, but you design an aircraft electrical for the type of aircraft and mission. I dont see anywhere in the near future that I will do long trips over water
with the Jabi. The VAAL Dam does not count.

I have flown an aircraft that both Alternators fail one right after each other.