Welcome to Club SAITO !
Senior Member
Join Date: Jul 2002
Location: Brunswick, ME
Posts: 1,192
Likes: 0
Received 0 Likes
on
0 Posts
I have a Saito 100 mounted horizonatally on a Hangar 9 Katana 50. It kicks and bangs at idle and despite my efforts to lean the idle mixture it still tends to idle very rough and will quit if it idles too long. It is also gobbling up a full tank of fuel on about 8 minutes and there seems to be raw fuel all over the carburator and dripping out of the cowl. I have installed an OS "F" plug as suggested by a couple of people and the engine has just returned from a checkup at Horizon where they said it ran fine. It will stay idling fine with the glow driver attached so it looks like onboard glow will have to be added unless there is something else I can adjust or try. I had a Saito 91 mounted in the same configuration and it would kick and bang the same way.
Jaybird
Jaybird
Senior Member
Join Date: Jul 2002
Location: Brunswick, ME
Posts: 1,192
Likes: 0
Received 0 Likes
on
0 Posts
No, it's not a backfire, but it does make a very load pop every couple of revolutions that shakes the whole plane. It's a very rough idle in this position. This engine was previously mounted inverted on another airframe and idled fine with the same OS F plug. It is newly broken in and doesn't have a lot of run time on it.
Jaybird
Jaybird
Can anybody tell me if the Saito 91 is much bigger and heavier than the FA82, or just a bit bigger/heavier? I am building a Hangar 9 Corsair 50 (not the 60) and am wondering if it would work with the 91. I plan on unsing a 3-blade prop on it.
Senior Member
Join Date: Jul 2002
Location: Brunswick, ME
Posts: 1,192
Likes: 0
Received 0 Likes
on
0 Posts
Jaybird
Senior Member
Join Date: Jul 2002
Location: Brunswick, ME
Posts: 1,192
Likes: 0
Received 0 Likes
on
0 Posts
Jaybird
My Feedback: (17)
Join Date: Sep 2002
Location: Nokomis FL
Posts: 145
Likes: 0
Received 0 Likes
on
0 Posts
Regards,
Jim
Last edited by SRQFlyer; 08-14-2013 at 11:42 AM. Reason: spelling
My Feedback: (102)
Join Date: Dec 2001
Location: Colonial Beach, VA
Posts: 20,370
Likes: 0
Received 25 Likes
on
25 Posts
Jay, you need to get that 1.00 out of the airplane and onto a test stand where you see it all. Set the HS needle at full peak rpm and leave it there, then throttle down to the lowest idle you can get and procede to lean the LS 1/8th turn at a time checking the transition after every other change. Also keep chasing the throttle downward as the idle improves. At some point the engine will hesitate when opening the throttle, turn the LS CCW 1/16th to 1/8th turn, be willing to sacrifice a few idle rpm for the best transition.
Senior Member
Join Date: Jul 2002
Location: Brunswick, ME
Posts: 1,192
Likes: 0
Received 0 Likes
on
0 Posts
Agreed and it will be set up horizontally so I can reproduce the environment it will be operating in. It ran fine inverted but there is something about the fuel flow it doesn't like laying on it's side.
Thanks for the help and let you know how it works out.
Jaybird
Thanks for the help and let you know how it works out.
Jaybird
Senior Member
Join Date: Apr 2010
Location: Cairns, AUSTRALIA
Posts: 1,053
Likes: 0
Received 0 Likes
on
0 Posts
jaybird, consider the following, air leaks, fuel tank position relative to the carby and general crap in the fuel (long shot). on the 65 comp engines we frequently split the fuel line ends (pulling them on and off to confirm fuel levels). considering horizon had no problems (taking them at their word?) it could well be the installation.
My Feedback: (15)
Join Date: Apr 2009
Location: Highland, MI
Posts: 360
Likes: 0
Received 0 Likes
on
0 Posts
Jay, you need to get that 1.00 out of the airplane and onto a test stand where you see it all. Set the HS needle at full peak rpm and leave it there, then throttle down to the lowest idle you can get and procede to lean the LS 1/8th turn at a time checking the transition after every other change. Also keep chasing the throttle downward as the idle improves. At some point the engine will hesitate when opening the throttle, turn the LS CCW 1/16th to 1/8th turn, be willing to sacrifice a few idle rpm for the best transition.
My Feedback: (15)
Join Date: Apr 2009
Location: Highland, MI
Posts: 360
Likes: 0
Received 0 Likes
on
0 Posts
just fyi to all I worked on a Saito 180 that had been sitting for a long while. we pulled the prop hub and found rusty bearings. we also found the con rod seized on the crank shaft. the con rod will have to be replaced. the bearings will have to be done too.
my question to the gentry is how do we tell what engine this is? 120,150,180. do we measure bore and stroke? Are all the con rods the same? FYI, piston, ring, cylinder all look good.
symptom was that the engine kept dead stick - ing. then when landed the prop was hard to turn
my question to the gentry is how do we tell what engine this is? 120,150,180. do we measure bore and stroke? Are all the con rods the same? FYI, piston, ring, cylinder all look good.
symptom was that the engine kept dead stick - ing. then when landed the prop was hard to turn
Senior Member
Join Date: Apr 2010
Location: Cairns, AUSTRALIA
Posts: 1,053
Likes: 0
Received 0 Likes
on
0 Posts
assuming you have done all the usuals, bearings etc check and ensure that the crankshaft bearings are properly bedded. you might not believe it but one can get the alignment of the bearings skewed and even 1 degree misalignment can case the sort of problems you are talking about.
depending on the series bore size is a good start to check engine size. problem i find with these engines is that capacity is usually varied by the size of the con rod which leads to other interesting situations. the best one i had was an os 20 fourstroke that went like a bat out of hell, couldn't figure why but it was good in comps, (i had bought it second hand). when i pulled it down i found it had os26 fourstroke car bits inside.
use the factory part numbers when replacing bits and you should be ok.
depending on the series bore size is a good start to check engine size. problem i find with these engines is that capacity is usually varied by the size of the con rod which leads to other interesting situations. the best one i had was an os 20 fourstroke that went like a bat out of hell, couldn't figure why but it was good in comps, (i had bought it second hand). when i pulled it down i found it had os26 fourstroke car bits inside.
use the factory part numbers when replacing bits and you should be ok.
My Feedback: (15)
Join Date: Apr 2009
Location: Highland, MI
Posts: 360
Likes: 0
Received 0 Likes
on
0 Posts
assuming you have done all the usuals, bearings etc check and ensure that the crankshaft bearings are properly bedded. you might not believe it but one can get the alignment of the bearings skewed and even 1 degree misalignment can case the sort of problems you are talking about.
depending on the series bore size is a good start to check engine size. problem i find with these engines is that capacity is usually varied by the size of the con rod which leads to other interesting situations. the best one i had was an os 20 fourstroke that went like a bat out of hell, couldn't figure why but it was good in comps, (i had bought it second hand). when i pulled it down i found it had os26 fourstroke car bits inside.
use the factory part numbers when replacing bits and you should be ok.
depending on the series bore size is a good start to check engine size. problem i find with these engines is that capacity is usually varied by the size of the con rod which leads to other interesting situations. the best one i had was an os 20 fourstroke that went like a bat out of hell, couldn't figure why but it was good in comps, (i had bought it second hand). when i pulled it down i found it had os26 fourstroke car bits inside.
use the factory part numbers when replacing bits and you should be ok.
My Feedback: (15)
Join Date: Apr 2009
Location: Highland, MI
Posts: 360
Likes: 0
Received 0 Likes
on
0 Posts
http://www.horizonhobby.com/pdf/Larg...der_Manual.pdf
Scoll down to page 15 and check out dimension E
Scoll down to page 15 and check out dimension E
Last edited by jkr_1100; 08-14-2013 at 07:08 PM.
My Feedback: (15)
Join Date: Apr 2009
Location: Highland, MI
Posts: 360
Likes: 0
Received 0 Likes
on
0 Posts
One more Hobbsy.
I just put new bearings in the FA-50. When putting it back together i put the dot on the cam gear down, when the crank is at TDC. Is this correct?
Bearings from RCBearing.com $11 plus a couple for shipping. I think $15.88 and here in less than a week. I always recommend rcbearings.com.
I just put new bearings in the FA-50. When putting it back together i put the dot on the cam gear down, when the crank is at TDC. Is this correct?
Bearings from RCBearing.com $11 plus a couple for shipping. I think $15.88 and here in less than a week. I always recommend rcbearings.com.
My Feedback: (102)
Join Date: Dec 2001
Location: Colonial Beach, VA
Posts: 20,370
Likes: 0
Received 25 Likes
on
25 Posts
I am a Boca fan, but we'll leave that alone, yes you timed it correctly and yes the dimension from valve cover top to crankcase bottom will tell you which engine is which. You have to have a good eye to tell the 1.50 from the 1.80. I may check out my 1.50 and see if the bore can accurately be measured with the back plate removed.
BOCA is a sponsor of this site so we need to take good care of them, their prices nearly equal that other guys with a coupon and free shipping.
BOCA is a sponsor of this site so we need to take good care of them, their prices nearly equal that other guys with a coupon and free shipping.
Last edited by Hobbsy; 08-15-2013 at 04:37 AM. Reason: Add content.
My Feedback: (15)
Join Date: Apr 2009
Location: Highland, MI
Posts: 360
Likes: 0
Received 0 Likes
on
0 Posts
I am a Boca fan, but we'll leave that alone, yes you timed it correctly and yes the dimension from valve cover top to crankcase bottom will tell you which engine is which. You have to have a good eye to tell the 1.50 from the 1.80. I may check out my 1.50 and see if the bore can accurately be measured with the back plate removed.
BOCA is a sponsor of this site so we need to take good care of them, their prices nearly equal that other guys with a coupon and free shipping.
BOCA is a sponsor of this site so we need to take good care of them, their prices nearly equal that other guys with a coupon and free shipping.