Raptor 50 v2 comes to ground

[Slufoot]

Today i get my raptor back from the hobby store :smokin: ,fixing a big time tail shake ....The guy said that the engin was the problem ( not set right )....
So i am at the feild and i make 1 flight all is good the helie is perfect the new OS 50 Hyper is nice .. So i use 1st tank bring it in for landing ck the engin temp 168 deg .Smoking good
I go over the helie checking the blades stuff you allways ck. after aflight .. so i refuel take off and all is good fly maby 5 min thin POP/CRACK/BOOM the helie engin die maby 40feet from ground so i autorotate it to the ground for the first time ever , perfect landing .. This is the only thing good about this story .. I ck the eng. temp 470 deg eng so hot its melting the plactic frame :arggg: ........ What now , this engin is new , i use 1 gal of 30% fuel to break this engin in ,and this is not my first helie eng .. my first eng was an os37 it run perfect no problems any idea on this

[Badger50]

WOW, 478 degrees, did you have any steaks with you to cook?:) Just kidding my friend. That definately is not characteristic of an O.S. engine. Been flying mine for over a year with over 300 flights, and she still purrs like a kitten. Just some things I could think of are,
Needle valve may have moved to severely lean it out.
Did the fan or drive belt come loose? No load on the engine is certain death.
Was the fuel the same, bad batch maybe or something in the fuel line got caught in the needle valve to cause it to lean out, or a clog or cut in the fuel line. Or maybe the engine just decided to go bad for no reason. I'm sure others have more, but my little brain is only capable of only so much. hope you get it worked out. :thinking

[forjer]

Check the muffler bolts and head bolts. If any of them had come loose, it could have cause a lean condition which would result in a hot engine. Hope it's OK.

[BarracudaHockey]

Check the muffler bolts and head bolts. If any of them had come loose, it could have cause a lean condition which would result in a hot engine. Hope it's OK.

My guess is the head bolts. Might want to see if you melted a hole in the piston while you're at it.

[Slufoot]

I ck every thing all i can guess is that the glow plug was loose it was hand tite ,head bolts was good fuel line was new..... maby the glow plug wasnt put in tight .. but as hot as the engin got, every thing should be loose so ????????? i cked all the needle settings ,,,and the high needle was 1.7 turn out and the low was never messed with i dont have a clue ? I looked at the piston . it was BAD .it had a big hole ,like the whole top of the piston was gone from the ring up .. i mailed the eng . off today and changed everything back to a 30 . i will run the os37 till i get the 50 back Maby i will get to fly this helie sunday i fly only 1 time a week.. i work 6 days a week it sucks .
WITH MY LUCK LIGHTING will strike this helie

[guygate88]

Wow! Exactly the same thing just happened to me!
I'd had a pro do a full setup for me, including tuning the engine.
It was a cool evening I was hovering about, nothing fancy and never above 60 or 70% stick, about halfway through a tank the engine locked solid, I didnt have a temp guage but I couldnt keep my finger on the backplate for more than a second. It was hot!

By the time I stripped the engine out of the frame it had cooled down a fair bit and i was able to turn over by twisting the fan but it felt tight.

Now this is a pretty new engine, maybe 10 tanks old, and I still run it fairly rich, and it was smoking plenty right up to the moment it came down, so I dont think leaning out was the problem.

Now here's the strange thing. Once I'd removed the head I could easily turn the fan in the clockwise (normal direction of blades) but trying to turn it anti-clockwise it was really stiff.
I rebulilt it all and it ran fine but every minute or so it would just stutter for a nanosecond, I darent go above a low hover but after a tankful the engine was red hot again.

Here's some questions that could help me & Slufoot:

1) Would running the engine too rich cause it to overheat?

2) With the head off should I be able to spin the crankshaft in both directions with equal force?

3) If the answer to above yes, do I need new bearings?

Any help would be appreciated, thanks guys.

[Wyldman]

Check for a clogged tank clunk. The TT clunks are famous for early (like first flight early) failure. If it wasn't drinking properly, that would hot it up real good!

[Raptorman37]

the engine should definitely rotate smoothly both ways so something is going on there, i'd look at the bearings, if it got hot enough the plastic bearing cage may have distorted.
Also if the engine goes lean no matter how rich you set it, that is a sign of bad bearings, as the bearings wear they loosen up, eventually allowing air into the crankcase, if your rear bearing is bad, i will churn the fuel up so much i can foam up inside the motor, causing less fuel to make it to the combustion chamber. just a hunch, check all your fuel lines, clunk lines, muffler bolts, head bolts, backplate bolts. Try a new gallon of fuel, sometimes the fuel goes stale even though you kept the bottle closed.

[Slufoot]

Well i found the problem ,i changed every thing back to the os37 and 2 flights she is running hot 200 ---- 230 ...i pull the fuel tank off and the clunk line is very soft probly this ling is sucking together i will replace the fuel line tonight and fly tomaroe

[kas4j]

don't forget your header tank also. crappy fuel line got me twice.:thumbdown: use a good fuel tubing. first time was stock line. second time was a medium wall tube. thick wall will seem too stiff but it will loosen up after a few tanks. after all look what it did to the one in your tank. i fly with a few raptor guys, they suggested i change mine about every 50 flights or so.

[Raptorman37]

yeah, hayes black tubing or the sig stuff is supposed to be good.
i'd change the stuff out once every season, just cheap insurance.