Hydro lock on O.S. 50hyper.

[Badger50]

I'm sure there are threads out there on this topic, but help would be greatly appreciated. I run the 50hyp with CY MP5 pipe. Makes great power, but is a buger to start. After each run I drain the main fuel and header tank, take out the glo plug, lay the heli on the left pipe side, and use my starter to blow all the old oil and fuel out. This works great on my YS 91sr with the hatori pipe, and on my Redine 53. I still get wicked hydro lock the next time I go out to fly. Is there any real solution, or is this just the way it is? :confused:

[WayneBrown]

You need to adjust your low end needle, it's way too rich or you are not clamping off the inlet line when you refuel.

[Badger50]

I thought might be a probem too, but my low end needle is set to dead center, when I do the pinch test I get 2-3 seconds before she starts to speed up. The thing that is really perplexing is that, as soon as I'm finished with my after run proceedure, and put the glo plug back in, she is already in a hyper lock state and no fuel to be found anywhere. Go figure. Thanks for the reply. :lol:

[helical]

Are you using a fuel line clamp?

[Badger50]

Yes. Like I said, she is in a hydro lock state when I get done with my after run proceedure, before I put any fuel in it.

[WayneBrown]

the only thing that comes to mind is that you are so rich that unburnt fuel is collecting in the muffler, however if you lay it on it's side that should not be the issue..
Run without the gov for a flight or two and tune the engine, then try the gov again.
Other than that I'm stumped.

[Badger50]

Thanks for the advice Wayne. The thing is that I don't use a gov. My high speed needle setting is one turn out from completely closed. The other thing that I have noticed with the MP5 pipe is that it does not drain after you have completed flying. I have taken the pipe off and noticed that when you turn the front of the pipe down, a fair amount of oil drains out of the manifold opening, which would allow oil to drain back into the engine if it were attached. I am confused as all getout myself. Even the guys at Heliproz didn't have a good answer for me. Do you think it's the way the pipe baffles are designed? I don't have this problem with the Hatori pipes on my other 2 raptors. Do you think I should forego my after run proceedure, which I have read is a good thing to do, or maybe call CY enterpises. Your guess is as good as mine.

[WayneBrown]

I have no idea.
Could be an odd pipe without a bottom drain in the baffle.

[Badger50]

I was doing some tinkering tonight ( as usual), took the pipe off. Even with the pipe off and the glo plug in, the compression is so strong that is is difficult to turn over by hand with my hex shaft. Could it be possible that I am over tightening my glo plug? Or is the cylinder head too tight? There is still some oil in the crankcase, but I figure that is pretty normal. Any replies are welcome.

[WayneBrown]

All that's normal...

[Divot]

I think you are confusing a tight/dry engine with a hydrolocked motor.
I bet it is tough to start the first time during your flying day. Then all is fine.
If that is the case you starter/battery is a bit weak also.

[Raven_darkcloud]

Ya, I have done a hydro lock befor on my 60 (did not pay atention to tank level at fill up) and it striped the starter shaft and cup. I have found that on the os engines I have if i'm just before tdc then the compresion makes it hard for the starter to turn if I dont have a full charge on the bat. What I do is move the fan backwords to let the pistin get momentum first.

[Badger50]

Thanks guys for all the suggestions. I think Divot is onto something. I could infact be trying to drain too much oil out of the engine. She has well over 10 gallons of fuel through her so she shoud be well broken in. I also take great care to make sure my dynatron starter is fully charged before I head to the field. I run almost 24 volts through her, so she is plenty strong. Yes Divot you are correct, once I get her started, she does just fine the rest of the day. I think I'll stop my after run proceedure, and see how it works. Thanks again to all. :noteworthy

[awr]

I have the same engine in my Raptor 50. It's got less than a gallon through it and it's very hard to turn by hand due to the high compression.

I use a cordless drill (18 volt) with a hex shaft to start my engine. The drill I'm using has a
torque ring - allows you to set the maximum amount of torque on the drill (when you exceed the set torque limit , the drill makes a very loud clicking sound). I dial the torque down as low as possible so that I know when I'm hydrolocking the engine.

I'm sure there are some raised eyebrows but it works.


Wayne
Calgary, Canada

[Badger50]

Yeah, the drill thing works, that is until I stripped the one way bearings in my clutch on my Rap-90. I have found it less expensive to take out the glo plug, clamp the fuel line, and blow the excess fuel out of the engine with my starter. It's time consuming, but not as much as replacing the clutch. Oh well I guess if we knew everything when we started this hobby, we probably would'nt have started it.:YeaBaby:

[ghtracey]

I agree with the above. You'd have to have a lot of residual fuel to hydrolock the engine. Compression from the cyclinder being at or near TDC when you try to crank it is more likely. Unless I am laying mine up for more than a day or too, I just tilt it up and let the muffler drain and leave whatever is in the engine in there. Sometimes being too clean can be a problem, some things need the oily mess left on them. :P

My TT50Pro starts instantly every time, I give about a 1 sec burst with my finger over the exhaust for the first start of the day, every other time, just ignite and crank it. It'll sit there and idle until I run the tank dry.

[Badger50]

Yep, finally figured it out. When I'm done flying, drain all the leftover fuel out of the tank and let her be. I tried it today and she started up in a snap. Goodbye after run proceedure. At least on this heli. Heck I'll try it on all of them. Thanks again for all the great advice. :noteworthy