700n Engine Alignment with Clutch

[waveydavey]

Anyone had issues with the one way in the clutch binding up a bit when the engine is fastened in the frame. Someone pointed this out yesterday and for the life of me I can't get it to run smooth. Short of installing a bit of shim behind the engine (YS91) fastening bolts I don't think it's going to line up.

Any tips?

[pgkevet]

I can't think of an easy reason why that might go out of alignment in the first place... assuming it has to have been fine before. Test the one way and starter out of the heli to be sure there's nothign wrong with that..recheck assembly of the clutch stack and bearings if you've had those apart..after that if it was a crash the next trick is to slacken off all frame bolts then re-tighten in case the frame has become stressed.

Do you remove engine with the frame bolts to engine fixing or just the engine to engine blocks?

[mark_w]

I have the same engine and its ok. How far out is it?

[tonystevens]

How much binding are we talking dave? mine doesnt run completely smooth but its never caused any bother but i know chris p had to put a shim between his engine and mounts to get proper alignment but im not sure if that was him just being slightly anal or not lol. its an align at the end of the day so unless its obviously well out of alignment id not worry too much it'll probably be fine.

[coolice]

Hi Dave.

I seem to remember there being a problem on some 700N's.
One fix is to take out the starter/clutch stack assembly at the top of the engine and elongate the alignment cutouts which the plastic assembly tabs locate in and then the securing bolts, to allow a little movement for this assembly to self align.
In fact, I have Vaughans Turbine next to me to remove the fan to check it's in balance and I've had to do the same on this model, as when I nipped up the screws the start shaft got tight to turn.
It's not by much, but any misalignment here causes the assembly to run tight and can lead to vibes.

Another option is to open up the engine mount holes, or machine a few thou off them or pop some shim steel inbetween the engine crankcase and mounts to push it towards the back of the model a bit.
Does it free up if the engine mounting bolts are left loose? If so it will be easy for you to grab some shim steel I am sure from work.
.

[waveydavey]

Thanks guys, thats what was pointed out to me yesterday. It's a bit stiff to turn but not horrible. I'm as you say Tony a bit anal about these things, I fitted the metal bearing housing so I'll give the frames a bit of a file.

[Tim Procter]

Hi Dave.

I had similar problems back in my 700n days.

Have to be honest it was a pain and very little I could do about it, I even bought an adjustable engine mount but still had some binding.

Funny thing was I broke the frames in a crash and it was perfect after the rebuild leading me to think the frames wasnt just perfect from the factory.

[Andy from Sandy]

Your model has standard bolts and not the supplied Align shouldered screws holding the engine mounts in place. I think you will find you can move the blocks around a bit to get a better alignment.

[waveydavey]

They're shouldered Andy, they're the Lynx upgrade ones.

[Andy from Sandy]

Well get some normal ones then to allow for movement. lol!

[waveydavey]

I think I'll probably go for Ian's fix and make a little bit of movement in the starter assembly. Cheers chaps