Tee Bee

Look what's protruding thru the crankcase. This was a new TD .049. I did some break-in runs last night at home, then took it to the field today and got 1 flight of approx 3 minutes before this happened. Never seen that before. Reckon it's still covered under warranty?

MJD

My Feedback: (1)

Did the piston seize or just the rod break?

Wow!

MJD

Tee Bee

Only the rod broke. The piston looks new. Maybe the starter cracked it prior to the failure?

skaliwag

My Feedback: (1)

Did it puncture the case?

icerinkdad

The starter was the first mistake... flood a Cox even a bit and the rod will break using a starter. Also the original Cox company went out of business several years ago. The folks that bought the company may be able to get you replacement parts but dont expect any warrenty work. Also if you were not using fuel with at least 20% oil and 100% of that castor the even the old Cox company would not guarantee an engine. Sadly the connecting rod is permanently connected to the piston and if the TD is old enough it had a tapered grind. Currently available pistons do not so will not run quite as fast. A Cox engine should start with a good flip with a "chicken stick" made from a dowel rod long enough to hold and engage the prop. Unless you are wearing a leather glove dont flip these by hand as the little prop cuts way too well....
Bob

Tee Bee

Yep. Poked out the bottom. I was joking about the warranty. Not my first .049, just my first rod failure. Maybe others have better luck(most likely skill), but I've rarely had any luck hand-starting these things. I use a Sullivan Hornet 1/2A starter. In this cold weather, I've had to use it even on engines that I normally can start with the spring snap-starter. The TD, though, isn't equipped with one.

Doc.316

Hum....looks like you need some JB weld?
Steve

gkamysz

My Feedback: (19)

Was the piston unusually tight in the cylinder?

Tee Bee

Not very tight. The engine was running great. The piston came out easily with no galling or marks. I wasn't really trying to start a debate on the use of starters, just thought that it was an interesting failure to share with other 1/2Aers. Hopefully a rare incident. I've assembled another TD made from TD .051, TD .049, and Surestart parts. Might get a chance to fly it tomorrow.

soarrich

My Feedback: (98)

A little duck tape for the case some CA for the rod, he's back in business

combatpigg

My Feedback: (3)

I've never seen one break like that on glow fuel with a normal sized prop.
The starter might increase the odds of breakage, but I've never broken a rod running glow fuel. The prop screw should fly off long before anything breaks.

ChicaWolverina

BTW: Tee Bee... was that a standard size starter with an adaptor or something, or an actual 1/2A size one? Brand & model?

><
Tomasina

Andrew

Tomasina: Tee Bee... was that a standard size starter with an adaptor or something, or an actual 1/2A size one? Brand & model?

Sullivan is an accepted hi speed, low power starter for 1/2A's.

Tee Bee -

That's tough snapping a rod and holing the case to boot. VintageGlowEngines or Xenalook might have a replacement piston. As mentioned, JB Weld applied to a very clean case could get you back into the air if you're able to locate a piston and rod.

andrew

Tee Bee

Thanks all. I've got replacement parts to repair it but in the meantime, I've assembled another "hybrid" TD .049 to get the plane running again.

Jim Thomerson

I got careless on piston resetting and have a piston with the rod poking through the top. I have blown a rod on a 15 first model Special.

On hand starting Cox 049, 09, 15 engines, here is some advice from an old Mouse Racer. Flipping is futile. Do a head prime, turn the prop backwards to vertical, light up the glow plug like a flashlight, and whop it forward with your gloved finger. With a little practice you will get one hit starts every time. Do use a glove. I think 1/2A's have shed more blood than all other sizes combined, just because people didn't respect them.

BobHH

My Feedback: (18)

Yep, broken a few rod and cranks over the years. Just one of those things. I generally hand start but do used a home made started if I'm running a bladder. I'm not sure what causes it maybe a flaw in the rod. I've run the Tee Dee .049s with 50 nitro back in my 1/2A racing days with very little issues as long as you reset the ball and socket.

If my memory serve me correctly I've had more broken parts issues using synthetic oils instead of the old castor. Matter of fact, I don't recall blowing an engine with all castor fuel.

Bob Harris

Raymond LeFlyr

My Feedback: (2)

From my CL racing days; a one flip start on a Fox .35 was often a good bet (cold . . . hot was another matter). Getting the same results on Mouse racers was a little less of a sure thing. But in either case the main ingredient was plenty of fuel (not too much) and a healthy whack.

See, violence IS the answer sometimes.

Springs (ptui) I laugh at pain and blood.

Didn't need no steenkin mufflers either.

gcb

Will JB Weld hold?

You might try Alumiweld to seal that hole.

George

Andrew

ROTFLMAO!!!!

Tee Bee

I'm the only 1/2Aer in my RC club so it's nice to come here and correspond with like minded crazies. Without a little humor, this aspect of the hobby could get a tad frustrating at times.

ProBroJoe

Yea, but what's funny is when they stop waxing on their 33% and 40% gassers to come over and see what you're up to! It's happened to me more than once - and I even got a "Hey, that's pretty cool."

-Joe

jeffie8696

A Little Extra is quaranteeeed to get a few looks.

DeviousDave

What's that Raymond? Your racing a mouse? I can't hear you thru my tinnitis....

(in wasted youth),

Dave