OS46H and Raptor 50 Titan

slink · Posted: Wed Jun 28, 2006 5:05 am Post subject: OS46H and Raptor 50 Titan

Hi there,

I have finally replaced an elderly Maverick with a Raptor Titan, and today tried to fit the existing OS46H into it. However, despite my best efforts, it doesn't fit...the end of the crank hits the bottom of the start shaft, not allowing the engine to go high enough to align the mount bolts.

Is this a known problem, and is there a known fix - like a different mount, or is it a case of resorting to filing something...

Thanks,
Steve.

Alex · Posted: Fri Jun 30, 2006 7:34 am Post subject:

Hi Slink
It sounds like the start shaft is not full pushed up when you are fitting the hex coupling or the gear is not screwed into the clutch. have you pics to show your setup?
_________________
Alex

barney · Member Joined: Dec 27, 2002 Posts: 80 Location: Inverness

When you fit the fan to the motor you must remove the crankshaft washer.

The fan is machined to be fitted directly onto the front bearing of the motor. Other possible maybe? engine mount upside down? Embarassed

Alex · Posted: Sat Jul 01, 2006 8:00 am Post subject:

barney · Member Joined: Dec 27, 2002 Posts: 80 Location: Inverness

All part of the service Laughing

but a possible

slink · Posted: Mon Jul 03, 2006 3:19 am Post subject:

Thanks for the replies! I'll see if I can get some pics tomorrow, but a few postings on Helifreak.com seem to think the 46 crank is indeed longer than the 50 crank, and it doesn't fit without a bit of minor surgery with a hacksaw - I'm thinking the surgery here may be the purchase of a 50!

I have checked through the install again, and everything is correct - the mount cannot go upside down as it's assymetrical, and the washer is indeed removed (although the engine actually fits the clutch with the washer fitted, but of course the mount still doesn't align).

Whilst on the subject, other than Marionville in Edinburgh, is there a decent model shop around the Falkirk / Stirling area, and has anyone got any info or contact details for the Falkirk Model Flying Club?

Thanks,
Steve.

geeo · Member Joined: Feb 04, 2005 Posts: 61

CMF hobbies in glasgow is not bad, i think they have some raptor bits too, good for fuel.
Falkirk clube meets at a farm Smile

sorry dont know the name on sat/sun up from the pineapple just outside Airth, best just to pop along or PM Alex on here for more info.

Ps i have a hyper 50 for sale if you are interested £80 low use (3 gallons) Razz

PPS @ Alex the site not work in firefox, cant login Sad

Alex · Posted: Mon Jul 03, 2006 8:01 am Post subject:

If you have a look at this

You will see its 66mm from the top mounting hole to the top of the clutch
check yours

Geeo why have you a hyper for sale??
_________________
Alex

geeo · Member Joined: Feb 04, 2005 Posts: 61

Picked one up from a dude in america but am converting/rebuilding completley old 50 sx-h i have, wanna buy it, nice engine and cheeeeeeap Smile

slink · Posted: Tue Jul 04, 2006 5:36 am Post subject:

Above is a pic of the engine assembled with the mount and clutch.

The engine measurements, taken from the engine block mounting hole nearest the front (i.e. the clutch end), with the crank pulled out to remove free play are:

Mounting hole - front edge of crankshaft taper (the fat bit on the crank) = 51mm.
Mounting hole - end of crank = 76mm.

The mount measurements, taken from the engine mount forward hole (eg the hole nearest the front) are:

Mount to end of main bearing housing (edge of engine block) = 23mm.
Mount to end of clutch = 66mm

As the 66 mm is the same as Alex's, I can only think it is the crank length that's the problem, as the clutch seems to fit ok, but the bottom of the starter shaft hits the end of the crank.

Steve.

Alex · Posted: Tue Jul 04, 2006 7:02 am Post subject:

OK now we are getting somewhere. If you measure the depth of the hole where the starter one way bearing sits, I get 12mm
_________________
Alex

slink · Posted: Tue Jul 04, 2006 7:28 am Post subject:

OK, inside the fan hub from the face where the clutch (or its shim) is bolted on to the bottom of the hub is 12mm. When the fan is fitted, the depth from the face of the fan hub to the end of the crankshaft is 2mm, which I suspect is the problem.

Alex · Posted: Tue Jul 04, 2006 8:28 am Post subject:

Have you time tommorow to bring it to our field at about 6:30 - 7:00
_________________
Alex

barney · Member Joined: Dec 27, 2002 Posts: 80 Location: Inverness

Had a wee look up OS part no's for the various motors

the OS 50 H & the Hyper 50 share the same crank

The OS 46 FX H has a different pt no for the crank.

slink · Posted: Tue Jul 04, 2006 9:15 am Post subject:

Alex,
Sorry, no time tomorrow or Wednesday as I'm working 1400 - 2200, but I'm then off until Monday morning, so will bring it on Sunday if I come over. I'm leaning more and more towards buying a 50 though, as there have been some pretty negative comments about the 46!
Steve.