HKS-700E restarted.

[rwaltman]

I'm working on putting my KF-IV back into service.

Today I started the engine, (an HKS-700E with ~80 hours,) after 2 and 1/2 years of inactivity.

Asked for, and received advice, ranging from the equivalent of "count the plugs, if you have four fly it" to "it's probably a total loss."

The last thing done to the plane (by an A&P) was install a new battery, new plugs, new oil and fuel filters, and drain the oil and gas tanks.
The last step was because I wanted to fill the tanks in small increments to calibrate the gauges and a measurement stick. I was also switching from Mogas without ethanol, (which the previous owner used but I could not buy) to 100LL.

So today, with great hesitation, the procedure was:

* Reinstall the battery - I had it at home hooked to a BatteryMinder in "maintenance/desulphating" mode for more than a week. Seems to have survived the deep discharge. (Odyssey PC680)
* Connect in parallel a DieHard jumpstarting unit.
* Fill in new oil
* Close fuel valve, Fuel pump 'OFF', Both ignitions 'OFF'
* Remove the plugs
* Spread a small amount of WD40 inside the cylinders via the plug holes.
* Repeat five times:
Crank the engine for 3-4 seconds, to pump some oil around.
Wait 4-5 minutes to allow the oil to spread.
* Reinstall the plugs
* Load 4 gallons of fuel
* Ignitions 'ON', Fuel pump 'ON', 'Clear Prop!'
* Start the engine, and the damn engine started!

I let it run for 5 minutes, oil temperature slowly raised up towards normal, pressure was a bit low, but I never gave much power. EGT ~1000, CHT very low, I suspect the senders or instruments are bad.
Shakes as hell below 2200 RPM, relatively smooth above 2500.
I wanted to do some taxi testing, but decided to wait because I wasn't sure about the brakes condition.

The plane is scheduled for annual inspection tomorrow. The guys are up to date with the plane history and condition, and I asked them to be more thorough than with the 'regular' annual. They should double check the engine, run a compression test, sync the carbs, etc. I'll also do an oil analysis with the company they normally work with.

I'll be there during the procedure.

Crossing fingers,

Roberto.

[Av8r_Sed]

I would recommend tearing down / cleaning the carbs thoroughly. A clean carb is a good starting point for tuning your motor.

[rwaltman]

I would recommend tearing down / cleaning the carbs thoroughly ...

Yes, thanks, that is the most common recommendation I received, that they may have "gunked up"
I asked the people doing the inspection to open, check and clean the carbs even if the engine seems to run fine.
( In the future I plan to do as much of the maintenance as I can, but this time, due to the “special circumstances”, I am leaving everything to the A&P)

News from the inspection front:

Unfolded the wings to be ready to move the plane, under its own power, from the hangar to the shop and was greeted by a fuel leak on the passenger's side. One of the hoses coming from the tank developed a crack. Luckily this happened on the ground.
The previous owner never folded the wings, I believe the same holds for the one before him.
I need to fold at least one wing after every flight to make the plane fit in a half-T hangar, I am stressing oldish and semi-dried hoses that didn't have to move till now.
Therefore I asked the A&P to replace all the fuel lines on both sides.

So, instead of the Kitfox moving majestically under its own power, the wings went aft, and if you saw three guys moving a funny looking yellow plane with folded wings in KMGJ that was us.

Once in the shop, a small leak was found on one of the oil tank fittings – O-ring needed, or something equally trivial. All electrics are good, all lights work, the wheels are still inflated, a CHT sender I though was bad wasn't.

I described to the mechanics the steps I followed to restart the engine and asked if I did anything that could have damaged it. They say no. Best of all, the engine agreed by passing the compression test with flying colors. (Pun intended. From memory, 175/179)

They didn't have the right type of fuel lines on hand, so the plane will remain there for a few days, but other than loosing the instant-gratification factor, things are looking good!

By the end of the week, give or take a couple days, for the first time since I bought it both me and the Kitfox will be legal to fly.

Roberto.

[Mnflyer]

Hi Roberto, yes to replacing all the old fuel lines / hoses once they have had fuel in them and then sit dry with no fuel for a time they dry rot and will leak, if fuel had been in them they would have been ok. Sounds like your getting close to doing some flying. Keep us updated, your going to like the HKS, they start right up and run great and burn only 3 GPH. Did you get the carbs synchronized, that will make a big difference on idle smoothness. I can idle mine at about 2000 for warm up and after a flight for cool down it idle very nicely at 1700.

[rwaltman]

... Did you get the carbs synchronized, that will make a big difference on idle smoothness.

I asked the A&P to do it. If for any reason he can't, I'll do it later. That, and prop balancing.
Somebody mentioned bringing a prop balancing tool to the NE Fly-in, which I am planning to attend. Most likely my KF won't be there, but at least I can learn about the process and arrange to do it at a later date.

I can idle mine at about 2000 for warm up and after a flight for cool down it idle very nicely at 1700.

Thanks, I'll keep these as references. What type of fuel do you use?

Roberto.

[Mnflyer]

Hi Roberto, 91 octane non alcohol auto gas, I have run maybe 10 /15 gals of Av Gas over the years. What prop do you have on the engine, the lighter the prop the smoother it will idle also, I have a 68" 2 blade Warp Drive and am very pleased with it. If I were to change I'd go with the Aerolux that APSU HKS Engines & Support sells. I have a very simple prop balancer but it works good but the biggest thing is to gat the carbs synd. Good luck hope your in the air soon.

[rwaltman]

> 91 octane non alcohol auto gas

That's what the previous owner(s) run on mine, but I can buy it around here.
I'm just curious about what performance/behavior changes can be expected when switching from Mogas to 100LL.

> What prop do you have on the engine, the lighter the prop the smoother it will idle

A 3-blade Powerfin. Don't remember the diameter now. I trust it was chosen by people that know more than me.

> hope your in the air soon.

That's the plan

Roberto.

[Mnflyer]

Hi Roberto, you will not notice much if any change switching to 100LL, but it is recommended that you change the oil every 25 hrs. Also I recommend to use Decalin Runup fuel additive to help with the lead savaging.
http://www.aircraftspruce.com/search/search.php

[rwaltman]

... What prop do you have on the engine, the lighter the prop the smoother it will idle also

Was thinking about this - Shouldn't it be the other way around, the heavier the prop the smoother the operation?

As in, the larger the moment of inertia of the propeller, the more it behaves as a flywheel to even-out the piston's firing and vibration?

Roberto.

[Av8r3400]

The motor (like a Rotax) has its own flywheel. The heavier prop just makes more pronounced the (necessary) gear lash in the reduction gearbox due to the torsional power pulses at low rpm. That is why the lighter the prop the better.