TT50 Fan installation

[OziPaul]

Hi All,

Building my first kit - a Titan 50. Various experienced pilots have warned about getting the fan tight on the engine or it will come loose the first time the engine is started.
So, I've read everything I could find on installing a Raptor fan.
Both RaptorTechnique and Team-Raptor suggest that it is not actually the fan which needs to be screwed down really tight but the nut which holds the fan. RT says something like "don't be an incredible hulk" and T-R says "slight to moderate pressure".
My plan then is to jam a plastic toothbrush handle down the inlet port, grab the fan and torque it down with "slight to moderate pressure". Then I'll make up a tool to hold the fan (using some 3mm bolts - not the ones from the kit in case they get weakened - where the clutch will attach) and use this to hold the fan while I tighten the nut "really tight" with a socket. As suggested, this should take the load off the engine internals. Of course I'll use blue threadlock on the threads.
However, being a newbie at Raptor construction (but definitely not at mechanical stuff in general), the terms "slight to moderate pressure" and "really tight" are (of necessity) very subjective and probably mean quite different things to different people. I personally wouldn't feel like putting too much oomph into the nut when it's being braced by two tiny 3mm nuts screwed into aluminum.

First question: Are my assumptions and suggested techniques correct?
Second: How did other newbies get this right first time or did most of you err on the side of caution and have the fan come loose? Or even worse damage something with too much torque?

Thanks,
Paul.

[Mike C]

OK Confessions :oops:

My first fan came loose :roll: ,,, I hadn't read anything and didn't know ( It will trash a motor)

You have read and do know :wink:
Tooth brush works fine,
We really have to count on the locktite doing it's job here, as you stated you can only put so much pressure on these small parts.

So the only thing I will add is to make sure that you have cleaned oil from parts before using the locktite.

If you ever have a hard time starting the heli , Make sure the fan has not spun loose :wink:

[OziPaul]

Thanks Mike,

I'll give the parts a good clean. I might also do the fan tomorrow and give the threadlock a chance to do its stuff. I won't be starting the engine for at least a week.

Cheers,
Paul.

[Rodan]

It's best to use the crank holding tool for this, but the toothbrush method appears to work. Definitely DO NOT use one of the tools that screws into the glow plug hole. I've seen several reports of damaged pistons from those...

I just went through this last week, as mine unscrewed. I added a lock washer between the nut and fan, but I'm not sure that will help, as they seem to unscrew together. Just loctite the crap out of it and hope for the best... and inspect routinely :wink:

[Mike C]

Clean it up , make the fan tool and pay attention - You won't have any problems :wink:

[BarracudaHockey]

Crank lock is best.

Clean the threads before applying locktite.

Let the locktite dry over night before attempting a start.

[Tintin]

Do not jam the toothbrush down the inlet port as you might damage pistonrod/bearings.
Take off the backplate and jam the crank in the same way you would with the crankcase tool.
Make sure to remove the washer before you put the fan on. Hold the fan with a towel or t-shirt and screw it down tight. It's very important to screw it down far enough (all the way) as otherwise it may come loose. You don't need to be a hulk even if it will feel like you're damaging it. I wouldn't screw on anything and use it as the holes not built to take a load that way and it's not necessary.