Thorp Air Command - T18.net

If your elevator hinge is built to plans, the bolt is not the hinge pin. The bushing is the hinge bearing. The bolt captures the bushing. Since the bolt and bushing don't move, the AN365 is the correct nut.

_________________
Bob Highley
N711SH
SN 835
KLAL

Good info John. I really appreciate it.

Successful engine start on Saturday after all the new wiring and throttle/mixture cables were hooked up. The engine sounded great and we took it up to 1700 RPM.

This Lycoming O-290G engine has 191 hours on the tach since converted to an aircraft engine. This is the original engine since N12055 was built in 1974. It is a low-time engine and then sat in a dry hanger for 12 years before I bought the aircraft. I started it two years ago and it ran great, then I removed the cylinders/pistons a year ago to change the O-rings and pushrod seals. There is no corrosion on anything we inspected such as the camshaft or wrist pins, pushrods, etc.

Question - I'm assuming that the rings are seated properly from the '70's. So, in your opinion, is it best when I'm flying it to either 1) run it normally because the engine is already broken in or 2) run it harder to ensure everything is still seated. I'm planning to use regular aviation oil and nothing special.

_________________
John Twigg N12055 SN.79 Pittsburgh, PA (KFWQ)

Congrats John. I would think the engine should be good to go. But you dont have to guess. Use your instruments. Check the oil temp, CHTs and oil consumption. Check the quality of the oil within a few tenths.
Cubes

Compression test ? If all #'s are good I would do what Cubes said .

RB

A compression test before running doesn’t hurt but is of very limited value. A cold test will normally yield lower than normal results. If the cylinder walls were oiled/greased during reassembly then they will likely test higher than normal. About the only thing a compression test at this point would reveal is a bad valve (which there shouldn’t be any since since it was just reassembled). I usually wait around 10 hours if I am curious about compression after performing top maintenance to give things a chance to settle in.

_________________
Thorp T18
O-320-B3B (160 HP)
68x74 Sterba Propeller

"The joke in aviation is, 'If you want to make a million, you'd better start with £10m.' " -Bruce Dickinson

Just got back from vacation in New York today and back out to the airport tomorrow (Sunday) to work on N12055. The brakes are rebuilt with new o-rings and I received the new hoses yesterday. Got my full coverage insurance for her this week. The (hopefully) final inspection is scheduled for Sat, 9/29. Lots to do yet!

_________________
John Twigg N12055 SN.79 Pittsburgh, PA (KFWQ)

Hi Cubes,

How does October look for transition training? I'll be vacationing the first week of October, but the rest of the month is good for me. This training is contingent upon N12055 passing her inspection on 9/29,

I tried to PM you twice about this, but it’s not sending for me...

John

_________________
John Twigg N12055 SN.79 Pittsburgh, PA (KFWQ)

Hi Jeff and Rich,

I’m going to take your advice (and Cubes) and do a warm compression test probably after doing numerous taxi tests.

I ran the engine again today and it started very easily. It has no mechanical or electric fuel pump, so the best practice found so far for cold starting her is to do 1-2 pumps of the throttle, throttle to idle, then pull about 6-8 blades by hand until I smell gas, then climb in and hit the starter with the throttle cracked. It fires up in 1-2 blades. Hot start was just as easy with throttle cracked and hitting the starter.

I’ll tell you she has good compression pulling the prop by hand!

_________________
John Twigg N12055 SN.79 Pittsburgh, PA (KFWQ)

Hi John,
I have Thursday starts in October (Thursday, Friday Saturday). In fact, I'll be in PIT 11, 20, and 25 October.
My number is 702 232-4261. My wife and I leave this Tuesday until the 28th to celebrate our 30th anniversary. We will be in BoraBora, so I'm not sure if I'll get any messages until the 28th.
Cubes

Happy Anniversary, Cubes! I'll see you when you get back and I'll PM you now that its working for me.

_________________
John Twigg N12055 SN.79 Pittsburgh, PA (KFWQ)

Hi All,

N12055 had her first taxi on Saturday and I taxied her again last night. I really like how she handles on the ground. There is no mechanical or electric fuel pump, but nevertheless starts very easily. I pump the throttle twice, pull the prop thru 6 times to get fuel into the cylinders, and hit the starter. Only 1-2 blades and the engine's running. I'll try starting next time without pulling the prop through. Just taking baby steps for now.

My IA found four mandatory squawks for me to fix:

1. a nut at the bottom of the co-pilot stick that didn't have 2 threads past nut. I had seen it and had already acquired a low-profile steel lock nut to change it, but didn't change it before the inspection. Good eyes. It's changed now. I use the same steel lock nut on the pilot side.

2. the IA found a wire too loose on my generator - the stud threads were stripped. I pulled the generator and it's at the generator shop getting its studs replaced. In a year or two I'll replace the generator itself, but for now I don't want to redo the bracket and pulley alignment. I want to fly it.

3. The flap springs were both rubbing against the bottom of the rear spar. Cubes and I messaged about it and said this is a rather common problem and I will bend the springs slightly the next time I'm at the airport. Cubes can explain better if he wants or maybe the forum knows all about this.

4. One of the prop flange lug nuts was spinning in the prop flange causing me not to be able to tighten the bolt that holds the prop extension on. It's supposed to be an interference fit. Fortunately, I was able to get the bolt back out without the lug spinning. Whew! Some ideas given to me by EAA boys were to raise some metal on the lug by using a center punch or by knurling it. If I don't do that, I'll get new lugs from Saber Engineering. What are you all's thoughts?

The IA will be back out in two Saturdays.

_________________
John Twigg N12055 SN.79 Pittsburgh, PA (KFWQ)

Looks like a good plan to me.

I don’t like reinventing the wheel so, when it comes to alternator conversions, I prefer to buy a conversion kit. That solves all of the bracket and alignment problems and can have the plane ready to fly again in less than a day. Granted, it does cost more but in terms of time, aggravation and quality of installation (no oddball connectors spliced in) I consider it money well spent.

_________________
Thorp T18
O-320-B3B (160 HP)
68x74 Sterba Propeller

"The joke in aviation is, 'If you want to make a million, you'd better start with £10m.' " -Bruce Dickinson

Hey thanks, Jeff. I didn’t know such things existed! I hope one exists for an O290 unless an O320 would work. I’ll see what the word is from the generator shop is and then go from there. I appreciate it!

_________________
John Twigg N12055 SN.79 Pittsburgh, PA (KFWQ)

Gotta final-torque wing spar bolts at the mid-wing joint in the next couple of days. What do you guys do? Do you use the standard AN torque values for each bolt size? I'm only asking in case there has been a reason not to.

_________________
John Twigg N12055 SN.79 Pittsburgh, PA (KFWQ)