Broken pushrod on lightly used Saito 100
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Broken pushrod on lightly used Saito 100
Hi Guys,
I purchased a brand new Saito 100 in 2007 , broke it in according to the manual and flown it less that 12 times. I also set the valve clearance to .002-.003 after break-in . I pulled the vavle cover off today to do my winter maintance and found the broken pushrod. What would cause this, is this common on 4-strokes? Guess I will have to send it to horizon for repair.
thanks,
Frank
I purchased a brand new Saito 100 in 2007 , broke it in according to the manual and flown it less that 12 times. I also set the valve clearance to .002-.003 after break-in . I pulled the vavle cover off today to do my winter maintance and found the broken pushrod. What would cause this, is this common on 4-strokes? Guess I will have to send it to horizon for repair.
thanks,
Frank
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RE: Broken pushrod on lightly used Saito 100
I think that if you press the valve spring down the short end of the rocker will move up and away just enough. I'll try it on an .80 tomorrow.
#5
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RE: Broken pushrod on lightly used Saito 100
Iwould like to know what tach readings you are getting. I suspect it may be overrevving if its underpropped. It causes a lot of strain on the valvetrain.
#7
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RE: Broken pushrod on lightly used Saito 100
That isn't close to over reving on the ground. Saito says 11,000 rpm, so figure around 10,000 on the ground. It's a judgement call since we don't know how much it unloads in the air. I use about a thousand rpm for headroom.
I'm curious to see if Dave can slip one in on his 80.
I'm curious to see if Dave can slip one in on his 80.
#9
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RE: Broken pushrod on lightly used Saito 100
Well, You can slip the pushrod out of the socket by pushing down on the spring but the pushrod will not come up past the side of the rocker arm to get it out or the new one in.
I just remove the carb and back plate, then lift the cylinder/piston/rod off. Then install the new puchrod in the tube and stick it all back together.
I just remove the carb and back plate, then lift the cylinder/piston/rod off. Then install the new puchrod in the tube and stick it all back together.
#10
RE: Broken pushrod on lightly used Saito 100
I think I saw specs on an OS buggy 4-stroke engine that turned 20,000 rpms a few years back. Don't think I was dreaming. How did they do that?
#15
RE: Broken pushrod on lightly used Saito 100
I'm with w8ye in that it takes a real good flatblade screwdriver,a bit of muscle and a lot of luck to unlock the rocker pivot arm screw
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RE: Broken pushrod on lightly used Saito 100
ORIGINAL: Old Fart
I'm with w8ye in that it takes a real good flatblade screwdriver,a bit of muscle and a lot of luck to unlock the rocker pivot arm screw
I'm with w8ye in that it takes a real good flatblade screwdriver,a bit of muscle and a lot of luck to unlock the rocker pivot arm screw
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RE: Broken pushrod on lightly used Saito 100
There is a way, this is a .65, so if the 1.00 pushrod is not too fat.
http://www.horizonhobby.com/products...-qq-SAIE100#t4
http://www.horizonhobby.com/products...-qq-SAIE100#t4
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RE: Broken pushrod on lightly used Saito 100
I think its going to turn out that a valve was stuck open. Horizon is beyond fair with warranty issues but I can't answer that directly.
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RE: Broken pushrod on lightly used Saito 100
Well guys, thank you for all your help. I have been away from glow planes for a few years and flying electric planes and EDF`s. so I forgot allot. As it turns out , it seems that the rod was just stuck in the down position and after I put some air tool oil in the valve areas now it looks fine. I reset the valve clearance to .003 and everthing seems to be normal with the movment on the valves and rods. But I wondering if I should pull the rod out anyway to see if it is bent? I`m not sure why it would have stuck in the down position in the 1st place?
Frank
Frank