Warbird Information Exchange

I was taught that the length of hte prop blade on most aircraft coupled with the gearing can give you enough leverage to allow you to pull right though a minor lock withought realizing you are doing damage. If you think about that and the fact that the starter is coupled to the motor closer in to the crank and does not have the leverage of the blade it makes sense that the starter will actually have less of a chance to push into or through a locked cylinder.

On Thunderbird (and all of hte LSFM aircraft) we NEVER pull the props through by hand, alwasy using the starter and to my knowlegde that has never caused a problem.

Steve S

I was at the show in Starkville Miss. a few years ago And saw first hand a b-25 started without pulling the props through by hand. The # 1 engine started, but # 2 did about two blades then kicked back. A walk around inspection was made of the engine. It was then restarted took off and you sure could here it mis firing in flight. Landed and did not fly again that day.

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I hitched a ride to that show in the L-39 and remember that incident as well. I couldn't believe they took off as I heard it misfiring on run-up. Then they got the nose wheel cocked over on the B-25, and I thought they were going to break it off trying to power out of it. I also remember someone in a highly polished Mustang turned too sharp on the taxiway and put the taxiway light inside of the right gear. I was a little nervous flying back to Reform as I thought those guys might have used up everyone else's good luck!

Didn't see the mustang. I thought the B-25 was going to crash on those low passes. Spit pop mis pop.

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*When you meet a Veteran shake his or her hand and thank them. They earned your freedom*

Pull it thru, I trust my hand more than a clutch on a starter.

I have pulled thru R-2800s by myself, it can be done.

Back when I worked around air tankers I would see all kinds of different methods used. A lot of it was based on the captain of the airplane, we had one captain who had been flying tankers since there inception he was flying a DC-6 and his normal morning preflight was to go out and pull 9 blades through by hand on each engine. Had another crew on a P-2V that would pull 8 blades through on each engine in the morning. Then we had a crew on a DC-7 that would go fire up the APU and turn 12 blades through with the starter on each engine and shut the APU down. There was also a crew on DC-4 that pull the props through by hand, but in reverse of the standard rotation. The only time I ever pulled props through to check for oil in the jugs was when I was told to do so by the bigman in charge! Otherwise the only time I did this was when we were doing compression checks.
Scott..........

On the B-29 FIFI we use the starter to turn through eight blades, it has never failed us. We have found several oil filled cylinders using this method. What happens is the prop just stops, we go and pull the least accesible plug (it always is) and drain the oil. Go read Randy Sohn's excellent article about hydraulic lock on www.douglasdc3.com.

I would imagine that the crew chief/ plane captain pulled the prop through before the arrival of the Aviators when refering to the NATOPS manual. The crusty old timers I learned from told me to always pull the blades through, clutch or no clutch on the starter.
Hey, I just made my first post!

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All I did was press this red button here...

And an auspicious one at that! Welcome!!!!!

so you guys are talking about the thing where you grab a blade with one hand and put your body weight into it, hoping that it won't chop you into two halves, right? It's these little discussions that make me keep hanging out at WIX!

I always wondered why you turn the prop before starting --makes perfect sense now! thanks!

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"I knew the jig was up when I saw the P-51D-20-NA Mustang blue-nosed bastards from Bodney, and by the way the blue was more of a royal blue than an indigo and the inner landing gear interiors were NOT green, over Berlin."

Starter clutch only on the A-1E.

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Eric

"I spent most of my money on alcohol, women and skyraiders....and the rest of it I just wasted."

Russ you certainly opened up a can of worms. Seems the real only right answer to your question is...........it depends.

I pull everything through by hand. I've seen enough starters that have not been adjusted properly or catch the hydro lock on the fourth or fifth blade. That's a tremendous amount of inertia to slam against the the locked cylinder. We pull through slowly and at the first hint of resistance, we pull plugs. It's messy and it takes time but worth it. But it also needs to be said that inexperienced help pulling blades through can also end up being very expensive.

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The more I learn about aircraft, the more I realize I still have to learn.

I pull everything through by hand. I've seen enough starters that have not been adjusted properly or catch the hydro lock on the fourth or fifth blade. That's a tremendous amount of inertia to slam against the the locked cylinder. We pull through slowly and at the first hint of resistance, we pull plugs. It's messy and it takes time but worth it. But it also needs to be said that inexperienced help pulling blades through can also end up being very expensive.

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The more I learn about aircraft, the more I realize I still have to learn.

that was the idea - learn as much as possible. I also opened this up on the Yahoo T-28 group. As someone said, this has been talked about as long as there have been radial engines, and deservedly so. I've studied the books and know all the recommended proceedures, but I want to hear as much discussion as possible.

The most conservative recommendation came from Javier at Vintage Radials (who did my cylinders) - he said it was well worth the few minutes it took that if the plane had sat beyond 3 days, to quickly pull the lower two plugs and hand walk the crank through a couple of revolutions. With so much at stake in these older single engine planes, it seems good advice. I think also since we are blessed with some good shops here in Texas, I may pop the starter off to ensure the clutch pop off pressure is correct.

I am also opting for the tank shut off and sump scavenge - the "Darton Clean Kit" that has proven so successful in other engines along with the Airwolf filter.

See you at the field!