R50 starting problems

[Whirly-Girl]

Brand new setup, so I must have missed something in the big picture:

Went to the field to break-in and hover a bit today and I couldn't get my O.S. 50H to start. My starter shaft is spinning the correct direction according to the O.S. directions (counter clockwise staring down the shaft from above). Glow plug was good, glow starter was heating it fine, and fuel was traveling to the carb. After a few start attempts, the rotor head wanted to spin clockwise (from top) as the starter was engaged, but the engine was not starting. And I noticed the head would not rotate freely backwards...it locked and would only spin one direction. I stopped the start engine attempts when this began happening because something didn't feel right.

Where do I begin trouble-shooting this?

[Ivan]

I would suggest you look and see if the clutch hub started coming loose.

If it spun a few times, then locked up, I would suspect the clutch hub came loose and as it unscrewed, it got into the bell locking up the clutch.

Tighten everything down again and put a drop of blue loctite on the crankshaft nut, it won't happen again.

Other possibilities are a broken clutch dog, or it is so grossly bent that it won't let go.

If that doesn't cure it, let us know.

Ivan

[porsche]

What probably happend is the motor got too wet and locked up this would cause the clutch to unscrew and tighten up in the fan houseing. Seen it a few times already. like said before you need to locktite this down and tighten it real good, also make sure your low end needle is not too rich to start with,the manuel that came with the motor will show you how to set it. Mine was perfect from the factory but my 50h also locked and spun the clutch off. I retightend it even more and also used the locktite AGAIN and now no problem.. once you get the hang of this motor you will love it, I do. Alan

[ThBrtmn]

Like the above... it initially may have been too rich to start and then when it hydrolocked...it may have spun the nut. Had that happened before...Double check your lighter to see if you get some glow. Are you using a remote glow adapter? If so...check your routing and grounding. If you dont have a good ground all your doing is drowning the motor.

[Dan Lewis]

This same scenario has happened to me about three times. The other day it happened to someone I was helping. We dropped the engine, re-loctited and re-tightened the nut (extremely tight), put it back together and were ready to go. I use a small socket wrench and a rag - grab the fan firmly with the rag and put everything you've got into wrenching the nut onto the crank. I've learned that you can get these too tight. Use a good crank lock tool or the end of a toothbrush.

One other thing I do is keep the fuel line closed until it turns over, then once it starts, I reach down and open up the line real quick - typically there's enough fuel to start and I forget to open it, so this often works well by accident. You can tell your idle needle is too rich if you have to pinch the line continously as you walk out your heli, but a pinch just before spool up can help to get it spinning easier. The fact that these engines like to be rich on the low, low end doesn't help, so there can be a fine balance if you keep to low end rich as I do (that is, you leave the set screw for the low needle at the factory setting). I just give it a pinch every now and then until the engine is a bit older.

[rob_jones]

One thing that I haven't seen mentioned is that the low speed needle could also be too lean. When it's cold out, I have a heck of time getting the OS 50 in my Sceadu to start. But if I richen the low speed about 1/8 turn, it usually does the trick.

[Whirly-Girl]

Wow, thanks for the suggestions! I definitely think it hydrolocked. When I pulled the fuel line off to the carb, fuel dripped out. Now that my husband is home, I'll drop the engine and have him put all his brut strength into tightening this sucker down. I did it by myself the first time WITH loctite, but I just don't think I have enough oomph to get it done well enough. I should have this and my T-Rex fixed up for this weekend...will let y'all know if both were a success!

Jeanette

[wolfdad]

:glasses2:
WG,
Please take note of Bimmer3's input as well. I think the inputs probably identified the problem, however my experience with the "small block" OS engines, and, more specifically the .30 size, has been that in cold weather (40°F and below), if you are a tad on the lean side, these little guys will require richening (and, sometimes considerably) to get them started. I concur with the hydra-lock diagnosis and loosening of the clutch. Another interesting phenomena I have only run into in cold weather is when they start and run backwards....now, seeing that will blow your socks off.
Doc

[ThBrtmn]

I did it by myself the first time WITH loctite, but I just don't think I have enough oomph to get it done well enough. I


When mine did it...I switched from blue to red.... Us a good Crank shaft locking tool and have not had a problem since.
Like this
http://www.ronlund.com/Merchant2/merchant.mv?Screen=PROD&Store_Code=heli&Product_Code=OSMR1003

[Whirly-Girl]

Thanks for the help guys!!!!!!! My Raptor 50SE was a success yesterday! :glasses2:

I dropped the engine and had my husband really crank down that nut. It was a nice, warm day so I left everything at the factory settings on the O.S. 50H. It started and idled fine with the first touch of my starter! I picked it up into a hover and it lifted around half stick so I kept richening it until it lifted around 3/4 stick. After 2 tanks of hovering, I went through the third tank with some figure 8's and on the fourth I did some fast forward flight figure 8 turns. On the fifth tank, a buddy of mine took it up and did some 3-D moves with it. There is power to SPARE with this engine even while richened up!!! He likes the chopper so much that I think he is buying one to beat around this summer too!

Thanks again! Woo-hoo!!! First flights rock!!!!!!!!!!!!!!!!!!!!!!!

[ausheli]

These Hypers are awesome, just got mine leaned out properly on Sunday after about 5 gallons and the SE50 is a FREAKIN WEAPON

[tqcookie]

WG, keep up the good work on the forward flight. We will have to get together soon.