Saito Bearing Replacement

Saito Bearing Replacement

Post by pfrome » Tue, 03 Jul 2001 02:55:42



Hi,

I'm attempting to replace the bearings on a Saito FA-65 engine.  I've done
it before on an OS engine but I want to be sure I can set the timing on the
SAITO before I pull it apart.  Any ideas how to go about setting the timing?
On an OS engine you can look at the valve cam by removing the side cover and
mark the shaft position to cam position. I can't see the cam gear without
removing it and the timing will be lost by then.

Has anyone done this before and do you have any helpful suggestions?

Thanks in advance for your help!

Paul

 
 
 

Saito Bearing Replacement

Post by Bill bun » Tue, 03 Jul 2001 07:34:16


There is a punch mark on the cam gear which is supposed to be straight down with
piston at TDC. Unfortunately, when you drop the cam gear and housing into place,
you can't tell if the gear turned. Some recommend packing the gear housing with
stiff grease. The only way to be sure is to note the cam timing before you take
it apart and check it after assembling. Here is some info:

Now for the valve timing. Unless you have knowledge of the location of the
timing marks on the
cam and crankshaft gears, and know that they can be seen to mesh properly when
put together, my
recommendation is to use a degree wheel to learn the timing before pulling the
crank. A degree
wheel can be made very simply by tracing around a protractor on a sheet of
paper, turning it 180 to
make a complete circle. Mark off every 5 degrees, then mark one of these points
"0"TDC (Top dead
center).Go 90 degrees clockwise and mark 90ATDC (After etc.), 90 more is BDC
(Bottom etc.), 90
more is 90 BTDC (Before Top etc.). Now glue the paper wheel to a piece of 1\8
ply or aluminum
or whatever and drill a center hole of crankshaft size. Now mount the wheel in
place of the prop
using a spacer to tighten in place.

To determine the valve timing, mount the engine in a test stand or block with a
pointer at some point
on the wheel, preferably near the top. You can find Top Dead Center quite
accurately by inserting
a 3 or 4 inch piece of 1/16 music wire in the glow plug hole and gently turning
the crank. Go easy,
you don't want to pinch the wire. Approach TDC from both sides, split the
difference and holding
the crank from turning, turn the degree wheel so that TDC is at the pointer.
Repeat the operation to
see that you are right on the pointer. Now when you turn the crank with the
degree wheel, you will
see that at every other TDC both valves are open a little. This is the top of
the exhaust stroke.
Beginning at about 90 before TDC and turning the wheel clockwise, you will see
the intake valve
begin to open at some point before TDC. Locate this point exactly and make a
note of it. Then
continue turning to locate and note the point where the exhaust valve closes.
When you reassemble
the engine, make sure that the timing gears are set properly by repeating this
check. One tooth off
on the timing gear could be 10 or 20 degrees off and will seriously affect
performance.

 
 
 

Saito Bearing Replacement

Post by Brian D. Felic » Tue, 03 Jul 2001 08:23:19


Paul,

    There is a hole in the heel of one of the cam lobes on Saito engines. Put
the cam into the cam housing and rotate it until you can see this hold through
one of the push rod holes (actually the lifter holes). Insert a push rod into
this hole to hold it in this position while installing the cam housing. Rotate
the crankshaft until the piston is at T.D.C. (all the way up in the cylinder)
and install the cam and cam housing. Check the timing- you can do this by
rotating the engine until both valves are very slightly open at the same time,
and the piston should be at or extremely close to it's maximum travel toward the
top.

Best of luck,
Brian

http://users.ids.net/~bdfelice/

"You can always tell an Engineer....

but you can't tell him much."

Quote:

> Hi,

> I'm attempting to replace the bearings on a Saito FA-65 engine.  I've done
> it before on an OS engine but I want to be sure I can set the timing on the
> SAITO before I pull it apart.  Any ideas how to go about setting the timing?
> On an OS engine you can look at the valve cam by removing the side cover and
> mark the shaft position to cam position. I can't see the cam gear without
> removing it and the timing will be lost by then.

> Has anyone done this before and do you have any helpful suggestions?

> Thanks in advance for your help!

> Paul

 
 
 

Saito Bearing Replacement

Post by pfrome » Tue, 03 Jul 2001 08:37:16


Bill,

Thank you very much, I'll try this approach!  It's also good to know that
the marks are there on the gears but I couldn't have known that without
having first lost the timing.  I'll make degree notes before taking it
apart!  One step closer to completion!

Paul


Quote:
> There is a punch mark on the cam gear which is supposed to be straight
down with
> piston at TDC. Unfortunately, when you drop the cam gear and housing into
place,
> you can't tell if the gear turned. Some recommend packing the gear housing
with
> stiff grease. The only way to be sure is to note the cam timing before you
take
> it apart and check it after assembling. Here is some info:

> Now for the valve timing. Unless you have knowledge of the location of the
> timing marks on the
> cam and crankshaft gears, and know that they can be seen to mesh properly
when
> put together, my
> recommendation is to use a degree wheel to learn the timing before pulling
the
> crank. A degree
> wheel can be made very simply by tracing around a protractor on a sheet of
> paper, turning it 180 to
> make a complete circle. Mark off every 5 degrees, then mark one of these
points
> "0"TDC (Top dead
> center).Go 90 degrees clockwise and mark 90ATDC (After etc.), 90 more is
BDC
> (Bottom etc.), 90
> more is 90 BTDC (Before Top etc.). Now glue the paper wheel to a piece of
1\8
> ply or aluminum
> or whatever and drill a center hole of crankshaft size. Now mount the
wheel in
> place of the prop
> using a spacer to tighten in place.

> To determine the valve timing, mount the engine in a test stand or block
with a
> pointer at some point
> on the wheel, preferably near the top. You can find Top Dead Center quite
> accurately by inserting
> a 3 or 4 inch piece of 1/16 music wire in the glow plug hole and gently
turning
> the crank. Go easy,
> you don't want to pinch the wire. Approach TDC from both sides, split the
> difference and holding
> the crank from turning, turn the degree wheel so that TDC is at the
pointer.
> Repeat the operation to
> see that you are right on the pointer. Now when you turn the crank with
the
> degree wheel, you will
> see that at every other TDC both valves are open a little. This is the top
of
> the exhaust stroke.
> Beginning at about 90 before TDC and turning the wheel clockwise, you will
see
> the intake valve
> begin to open at some point before TDC. Locate this point exactly and make
a
> note of it. Then
> continue turning to locate and note the point where the exhaust valve
closes.
> When you reassemble
> the engine, make sure that the timing gears are set properly by repeating
this
> check. One tooth off
> on the timing gear could be 10 or 20 degrees off and will seriously affect
> performance.

 
 
 

Saito Bearing Replacement

Post by pfrome » Tue, 03 Jul 2001 09:31:23


Yep, I found it in the front lifter hole. I like this solution better than
marking the timing.

Thanks Brian!

PS, I like your web page, I had seen the wedge before!



Quote:
> Paul,

>     There is a hole in the heel of one of the cam lobes on Saito engines.
Put
> the cam into the cam housing and rotate it until you can see this hold
through
> one of the push rod holes (actually the lifter holes). Insert a push rod
into
> this hole to hold it in this position while installing the cam housing.
Rotate
> the crankshaft until the piston is at T.D.C. (all the way up in the
cylinder)
> and install the cam and cam housing. Check the timing- you can do this by
> rotating the engine until both valves are very slightly open at the same
time,
> and the piston should be at or extremely close to it's maximum travel
toward the
> top.

> Best of luck,
> Brian

> http://users.ids.net/~bdfelice/

> "You can always tell an Engineer....

> but you can't tell him much."


> > Hi,

> > I'm attempting to replace the bearings on a Saito FA-65 engine.  I've
done
> > it before on an OS engine but I want to be sure I can set the timing on
the
> > SAITO before I pull it apart.  Any ideas how to go about setting the
timing?
> > On an OS engine you can look at the valve cam by removing the side cover
and
> > mark the shaft position to cam position. I can't see the cam gear
without
> > removing it and the timing will be lost by then.

> > Has anyone done this before and do you have any helpful suggestions?

> > Thanks in advance for your help!

> > Paul

 
 
 

Saito Bearing Replacement

Post by Bob Tomasu » Tue, 03 Jul 2001 11:41:44


Quote:

> Hi,

> I'm attempting to replace the bearings on a Saito FA-65 engine.  I've done
> it before on an OS engine but I want to be sure I can set the timing on the
> SAITO before I pull it apart.  Any ideas how to go about setting the timing?
> On an OS engine you can look at the valve cam by removing the side cover and
> mark the shaft position to cam position. I can't see the cam gear without
> removing it and the timing will be lost by then.

> Has anyone done this before and do you have any helpful suggestions?

> Thanks in advance for your help!

> Paul

I haven't done this in a while (7~8 years), but the SA65/80/91 makes
use of a keyed hole in the camshaft. When you do the timing, remove
the lifter from the exaust side of the engine. The lifter can be
replaced from the topside after alignment is complete. Use the pushrod
as an alignment pin. Place the pushrod (from the top) down through the
hole in the cam housing cover into a predrilled hole in the camshaft.
This is the correct alignment. There's no mark on the gear as one
would expect. Install the cam in this alignment. Reinstall the lifter
and you're done.
 
 
 

Saito Bearing Replacement

Post by Al Womelsdo » Thu, 05 Jul 2001 00:35:20


In the manual it details how to set the timing. Once you get it apart
there is a hole or mark on the cam gear that matches with the crank
(as I recall it goes against the crank at TDC). These engines are not
that hard to work on once you get the first one under your belt!

If you need more help, check with Horizon or email me. I have an older
.65 as well.

Al



Quote:
>Hi,

>I'm attempting to replace the bearings on a Saito FA-65 engine.  I've done
>it before on an OS engine but I want to be sure I can set the timing on the
>SAITO before I pull it apart.  Any ideas how to go about setting the timing?
>On an OS engine you can look at the valve cam by removing the side cover and
>mark the shaft position to cam position. I can't see the cam gear without
>removing it and the timing will be lost by then.

>Has anyone done this before and do you have any helpful suggestions?

>Thanks in advance for your help!

>Paul