os 50 max

[Darkstar]

have a helicopter with an os50 max engine in it
Is the liner tapered?Have some compression but very weak engine starts but
will not tick over. Took the head of but piston looks ok but when detached
from crank will do full stroke and can be removed from top or bottom
therefore if this was a tapered bore it should not come out the top.Anyone
give me any ideas

[Ron van Sommeren]

The OS MAX 50 FSR has a Dykes ring (L-shaped). A Dykes ring uses the
pressure of the explosion for a tight fit to the liner, it expands.

Met vriendelijke groet ;-) Ron van Sommeren
near Nijmegen, the Netherlands
--
Anti-Spam: my address must be modified.
"Darkstar" <crashtest709@ntlworld.com> wrote in message
news:kmdlc.222$gv5.194@newsfe1-win...
> have a helicopter with an os50 max engine in it
> Is the liner tapered?Have some compression but very weak engine starts
but
> will not tick over. Took the head of but piston looks ok but when
detached
> from crank will do full stroke and can be removed from top or bottom
> therefore if this was a tapered bore it should not come out the
top.Anyone
> give me any ideas
>
>

[Beav]

"Darkstar" <crashtest709@ntlworld.com> wrote in message
news:kmdlc.222$gv5.194@newsfe1-win...
> have a helicopter with an os50 max engine in it
> Is the liner tapered?

Not unless it's an ABC engine (no piston ring) and as far as I can remember,
OS never made an ABC "Max". It's more likely to be a normal ringed engine.

Have some compression but very weak engine starts but
> will not tick over.

Sounds like either your mixture and plug need looking at, or the engine is
in need of a new piston/ring/liner which could prove difficult to find.

Took the head of but piston looks ok but when detached
> from crank will do full stroke and can be removed from top or bottom
> therefore if this was a tapered bore it should not come out the top.Anyone
> give me any ideas

I'd say that if your engine IS an old Max 50, it's about time it was laid to
rest and a new one installed.


--
Beav


Please note my E-mail address is "beavis dot original at ntlworld dot com"
(with the obvious changes)

Beavisland now lives at
www.beavisoriginal.co.uk

[Christer Buschmann]

> > have a helicopter with an os50 max engine in it
> > Is the liner tapered?
>
> Not unless it's an ABC engine (no piston ring) and as far as I can
remember,
> OS never made an ABC "Max". It's more likely to be a normal ringed engine.

Both ringend and unringed OS engines are usally ABC.

Christer.

[Beav]

"Christer Buschmann" <buschman@online.no> wrote in message
news:Whvlc.1510$Yc.23690@news4.e.nsc.no...
> > > have a helicopter with an os50 max engine in it
> > > Is the liner tapered?
> >
> > Not unless it's an ABC engine (no piston ring) and as far as I can
> remember,
> > OS never made an ABC "Max". It's more likely to be a normal ringed
engine.
>
> Both ringend and unringed OS engines are usally ABC.

I do believe you'll have to point me to a site that can confirm that
Christer.


--
Beav


Please note my E-mail address is "beavis dot original at ntlworld dot com"
(with the obvious changes)

Beavisland now lives at
www.beavisoriginal.co.uk

[Courseyauto]

The Saito 4 strokes have a chrome plated linner and a ringed piston.
AAC set ups are suppose to expand at a more equal rate,keeping the compression
higher when it heats up.
DOUG