Freya 60/70 sufficent cooling.

[mf_read]

Folks,

I have a Freya with an OS 70 installed, I've had 2 fried pistons in 2 months, I have had them replaced under warranty but I can't believe that this keeps happening.

I'm starting to look into the cowling that directs the cool air to the top of the engine block from the fan. The engine looks fairly exposed within the frames compared to the Xcell range of Heli's. Is the ducting/cowling sufficient for the cooling for this machine or are modifications being made to improve this.

I'm running Magnum 12.5% and a MPII which I've just replaced with a Hatori 999, As I concerned the the MPII with this fuel type is not suited.
Once I get my enigne back for OS, I will be running it with Magnum 20%


Regards

Mike

[mudbogger2]

The cooling on the Freya is sufficent if your needles are set properly.
You need to make sure you are not running it too lean.

The OS .70's had a problem burning holes in the pistons when they were first released but I thought they had resolved that issue.

[mf_read]

Jon,
Thanks for the reply, The magnum fuel is very smokey due to the high oil content 22% and this is deceptive when tuning, The engine problems I've encountered is hot and cold, 1 tank of fuel throught the heli and the sump is cool then I lean the high speed needle 1 click and re fuel and the engine comes back roasting hot. I'm surprised that 1 click has had so much impact. The gurus at our club have not thought that I've been running too lean as the performance of the heli has not been that great testing climb outs etc..... I know that too lean also means poor performance but whith all that smoke coming out its hard to tell.

I'm going to start from fresh again when I get my new engine and go "rich" and see if I can get it working, I've heard that MPII are difficult to tune on the OS70 with so little nitro, and 30% in the UK is far too expensive for us over here. Hopefully the Hatori 999 pipe will be a success!

Regards

Mike

[Jafa]

One click should not have such a dramatic impact
I would suspect loose material in the carb - strip it and clean it real good
I really like using those carb and brake cleaner products in an aero-can
They clean stuff and evaporate away - very good indeed

You may also have a pin hole somewhere,
fuel line or the tank bung
This can loose the exhaust pressure and cause a lean condition

Make no mistake, blasting a hole in the piston is due to running lean

I run a OS91 in the Freya - engine runs cool and produces good power
Never heard of a cooling problem in a Freya

[mroy0404]

This may help with your cooling problems, I don't mean to spam you just help.

http://i41.photobucket.com/albums/e288/mroy0404/hirobo%20fans/freyafan003.jpg

I can send one if your interested.