Welcome to Club SAITO !
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FlyerInOKC (02-08-2026)
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FlyerInOKC (02-08-2026)
02-07-2026 | 01:28 AM
Aidan, I consider the Saito 82 to be a super star as engines go. So smooth, that's a great looking plane. It looks like we both use the, "swing lever" method of connecting the throttle.
This throttle linkage allows me the put the throttle servos down with the others, bends.
This throttle linkage allows me the put the throttle servos down with the others, bends.
Last edited by 1200SportsterRider; 02-07-2026 at 01:35 AM. Reason: Add image
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FlyerInOKC (02-08-2026)
02-07-2026 | 01:59 AM
Yes Dave, we use the same method of throttle linkage. I have this on all my Saito powered planes. It works great and is ultra reliable. That's a great looking Saito 82 you have there. The best of luck with that and happy flying.
02-07-2026 | 04:24 AM
Thanks Aidan, I just finished building a second wing for the Super Squire with a 60" wingspan, sanding time now. The plan or my eye sight was a little off, the right wing half was 29 7/8" and the left was 30, I simply cut out an extra rib with no spar notches form 1'8" stock and slabbed it on there. Now were even up. The engine is a Saito 50 rebuilt by me and painted black, it too will wear a Turbo Header.
60" wing with 20 ribs vs. stock 56.25" stock wing with 18 ribs.
60" wing with 20 ribs vs. stock 56.25" stock wing with 18 ribs.
Last edited by 1200SportsterRider; 02-07-2026 at 04:32 AM. Reason: Add image
02-18-2026 | 03:33 AM
FA-150S carburettor rebuilt
Gent's,
This is a great forum, thanks for great posts and building pictures!
I'm rebuilding a Saito FA-150S and i have some questions on the carburettor rebuilding. As a background information, a friend of mine gave me the engine and I wonder if someone has messed up with the engine as it does not seem to produce the max rpm one would expect. Anyways, here's the thing:
-The cats eye position does not seem to be correct, see the pictures. My common sense tells me it should be oriented so it faces into the carb throat on the intake/air-inlet side. In other words, the cat's eye faces the air, not the engine and when the carb is mounted in the engine you have to be able to see the cat's eye when the barrel is open and you look through the venturi.
Is my assumption correct? And if yes, how can I rotate the spray bar? is it press-fitted and a tight fit so I first need to remove it completely first or how shall I do the job?
-another thing: The O-ring set I purchased doesn't appear to include an O-ring for sealing the spray bar assembly and or the the high speed needle valve assembly - see the pictures. Is this Ok? or should I use some method to seal the threads for air leaks, such as some thread locker compound or something? Or am I missing some O-rings?
Sorry, many questions but the Saito instructions are very vague and do not help much..
thanks in advance,
Artto
This is a great forum, thanks for great posts and building pictures!
I'm rebuilding a Saito FA-150S and i have some questions on the carburettor rebuilding. As a background information, a friend of mine gave me the engine and I wonder if someone has messed up with the engine as it does not seem to produce the max rpm one would expect. Anyways, here's the thing:
-The cats eye position does not seem to be correct, see the pictures. My common sense tells me it should be oriented so it faces into the carb throat on the intake/air-inlet side. In other words, the cat's eye faces the air, not the engine and when the carb is mounted in the engine you have to be able to see the cat's eye when the barrel is open and you look through the venturi.
Is my assumption correct? And if yes, how can I rotate the spray bar? is it press-fitted and a tight fit so I first need to remove it completely first or how shall I do the job?
-another thing: The O-ring set I purchased doesn't appear to include an O-ring for sealing the spray bar assembly and or the the high speed needle valve assembly - see the pictures. Is this Ok? or should I use some method to seal the threads for air leaks, such as some thread locker compound or something? Or am I missing some O-rings?
Sorry, many questions but the Saito instructions are very vague and do not help much..
thanks in advance,
Artto
02-18-2026 | 09:11 AM
Senior Member
My Feedback: (3)
To try and answer all your questions:
First, the cats eye should face towards the engine, basically down the pipe into the engine, (you should not be able to see it if looking into the carb). That is where the low pressure draw would be greatest.
As for the gasket and O-rings, I have 2 X 150s and a 180, but it has been a while since had them apart. Having said that, I just put together a 65, one 91 and a 100 last week so cat at least give some info on those.
The basic gasket kit does supply at least the tiny O-ring that fits just inside the end of the spray bar threads, where the needle would insert.
This provides the primary seal and is one of the most overlooked, (as well as tedious to install) so most often I see fuel tubing on the outside trying to prevent fuel leaks. If installed correctly it does work.
NOTE: As with other black BUNA N O-rings, they shrink, harden and crack with age/
There is another, very thing O-ring that goes on the outside of the spray bar once fit into the main body and is compressed by the needle spring base when the nut is tightened, However, I have rarely seen any issues even if missing since the spray bar is such a tight fit anyway. Try to avoid any Loctite or other sealants as there is the chance you can partially or fully block the fuel flow.
On that subject, I run and recommend filters on ANY 4-stroke. They seem much more vulnerable to FOD getting at the carb. The most critical aspect is the chance for a lean run at higher throttle. That is the recipe for a sudden stop, (and I mean SUDDEN!) with the very high chance of ejecting the prop at high energy, even with the double lock nut setup.
As for removal and installation of the spray bar: I normally thread the needle onto the end once the nut and needle spring are removed, as well as the barrel, and place them in a vice to slowly press it into the body. You will find it is pretty tight at first, but that should loosen as it goes in. You may have to back the needle out a bit and try again before it comes free.
To reinstall, I use a small piece of brass tubing, (similar to what is used for your fuel tanks) and a socket on the outside. The tubing goes on the spray bar and the socket on the outside of the carb to allow the assy to press into place again. There are no internal seals or O-rings used here, only that thin one on the outside.
As to your low power concern. I cannot help beyond stating there are a few typical causes, the first being overall mechanical condition of the engine, ie, compression.
Another mechanical concern is cam timing. It is easy to get it one or more tooth off on reassy if not careful and the fact your spraybar is off leads me to believe someone may have gone at this one with little experience or care so that may be a possibility.
Another is valve lash. I set mine all a bit tight, between 1 and 2 thou and check them before each season. Only if there is something that leads me there, they seem fine for the rest of the summer.
External issues can be the wrong prop, bad fuel, as well as improper mixture settings.
Oh, and that last one leads me back to mechanical condition: If the engine is new and not completely through break in, you will find it not reaching peak RPM.
Do you have a tack? You should see in the mid 9K range.
First, the cats eye should face towards the engine, basically down the pipe into the engine, (you should not be able to see it if looking into the carb). That is where the low pressure draw would be greatest.
As for the gasket and O-rings, I have 2 X 150s and a 180, but it has been a while since had them apart. Having said that, I just put together a 65, one 91 and a 100 last week so cat at least give some info on those.
The basic gasket kit does supply at least the tiny O-ring that fits just inside the end of the spray bar threads, where the needle would insert.
This provides the primary seal and is one of the most overlooked, (as well as tedious to install) so most often I see fuel tubing on the outside trying to prevent fuel leaks. If installed correctly it does work.
NOTE: As with other black BUNA N O-rings, they shrink, harden and crack with age/
There is another, very thing O-ring that goes on the outside of the spray bar once fit into the main body and is compressed by the needle spring base when the nut is tightened, However, I have rarely seen any issues even if missing since the spray bar is such a tight fit anyway. Try to avoid any Loctite or other sealants as there is the chance you can partially or fully block the fuel flow.
On that subject, I run and recommend filters on ANY 4-stroke. They seem much more vulnerable to FOD getting at the carb. The most critical aspect is the chance for a lean run at higher throttle. That is the recipe for a sudden stop, (and I mean SUDDEN!) with the very high chance of ejecting the prop at high energy, even with the double lock nut setup.
As for removal and installation of the spray bar: I normally thread the needle onto the end once the nut and needle spring are removed, as well as the barrel, and place them in a vice to slowly press it into the body. You will find it is pretty tight at first, but that should loosen as it goes in. You may have to back the needle out a bit and try again before it comes free.
To reinstall, I use a small piece of brass tubing, (similar to what is used for your fuel tanks) and a socket on the outside. The tubing goes on the spray bar and the socket on the outside of the carb to allow the assy to press into place again. There are no internal seals or O-rings used here, only that thin one on the outside.
As to your low power concern. I cannot help beyond stating there are a few typical causes, the first being overall mechanical condition of the engine, ie, compression.
Another mechanical concern is cam timing. It is easy to get it one or more tooth off on reassy if not careful and the fact your spraybar is off leads me to believe someone may have gone at this one with little experience or care so that may be a possibility.
Another is valve lash. I set mine all a bit tight, between 1 and 2 thou and check them before each season. Only if there is something that leads me there, they seem fine for the rest of the summer.
External issues can be the wrong prop, bad fuel, as well as improper mixture settings.
Oh, and that last one leads me back to mechanical condition: If the engine is new and not completely through break in, you will find it not reaching peak RPM.
Do you have a tack? You should see in the mid 9K range.
02-18-2026 | 10:53 AM
To try and answer all your questions:
First, the cats eye should face towards the engine, basically down the pipe into the engine, (you should not be able to see it if looking into the carb). That is where the low pressure draw would be greatest.
.....
The basic gasket kit does supply at least the tiny O-ring that fits just inside the end of the spray bar threads, where the needle would insert.
This provides the primary seal and is one of the most overlooked, (as well as tedious to install) so most often I see fuel tubing on the outside trying to prevent fuel leaks. If installed correctly it does work.
As for removal and installation of the spray bar: I normally thread the needle onto the end once the nut and needle spring are removed, as well as the barrel, and place them in a vice to slowly press it into the body. You will find it is pretty tight at first, but that should loosen as it goes in. You may have to back the needle out a bit and try again before it comes free.
To reinstall, I use a small piece of brass tubing, (similar to what is used for your fuel tanks) and a socket on the outside. The tubing goes on the spray bar and the socket on the outside of the carb to allow the assy to press into place again. There are no internal seals or O-rings used here, only that thin one on the outside.
.
First, the cats eye should face towards the engine, basically down the pipe into the engine, (you should not be able to see it if looking into the carb). That is where the low pressure draw would be greatest.
.....
The basic gasket kit does supply at least the tiny O-ring that fits just inside the end of the spray bar threads, where the needle would insert.
This provides the primary seal and is one of the most overlooked, (as well as tedious to install) so most often I see fuel tubing on the outside trying to prevent fuel leaks. If installed correctly it does work.
As for removal and installation of the spray bar: I normally thread the needle onto the end once the nut and needle spring are removed, as well as the barrel, and place them in a vice to slowly press it into the body. You will find it is pretty tight at first, but that should loosen as it goes in. You may have to back the needle out a bit and try again before it comes free.
To reinstall, I use a small piece of brass tubing, (similar to what is used for your fuel tanks) and a socket on the outside. The tubing goes on the spray bar and the socket on the outside of the carb to allow the assy to press into place again. There are no internal seals or O-rings used here, only that thin one on the outside.
.
I believe you covered it all - and now that I rethink the cat's eye orientation it's clear it has to point towards the engine intake manifold! (What the heck was I thinking? )
The O-ring kit includes the very small, maybe 2mm id, O-ring that seals the high speed needle. May only concern is how an earth will I be able to remove the old O-ring from the groove it sits in. See picture.
In the kit there is also an O-ring that seals the LS needle. This should be straight forward
On removing the spray bar with the help of a vice: would it be a good idea to heat up the carb body first? Or use WD-40 (which normally ruins O-rings but maybe Ok to use to help with releasing the spraybar, and then the WD-40 can be washed off )
Once again, thank you so much!
-Artto
02-18-2026 | 12:53 PM
Senior Member
My Feedback: (3)
I've never had to use anything when pressing the spraybar out, or back in. Just remember to use the needle rather than try to press the end of the spraybar directly.
I would have to pull one of my big blocks to confirm the size of that lock nut holding the spring and spraybar, as well as confirm if the same as the smaller engines.
As for that O-ring, I use a standard T-pin. Just be careful not to scratch the brass. Most of the ones I've done are pretty brittle so break into small pieces. As with using a filter to prevent any contamination, you want to ensure anything is flushed out before reassembly.
Inserting is where you will have the most fun. I found a small diameter wire inserted in the hole to allow the O-ring to slide down one of the easiest methods. Then carefuly push it into place, (again, trying to prevent scratching or damage to the O-ring.
I would have to pull one of my big blocks to confirm the size of that lock nut holding the spring and spraybar, as well as confirm if the same as the smaller engines.
As for that O-ring, I use a standard T-pin. Just be careful not to scratch the brass. Most of the ones I've done are pretty brittle so break into small pieces. As with using a filter to prevent any contamination, you want to ensure anything is flushed out before reassembly.
Inserting is where you will have the most fun. I found a small diameter wire inserted in the hole to allow the O-ring to slide down one of the easiest methods. Then carefuly push it into place, (again, trying to prevent scratching or damage to the O-ring.
02-18-2026 | 01:01 PM
I've never had to use anything when pressing the spraybar out, or back in. Just remember to use the needle rather than try to press the end of the spraybar directly.
I would have to pull one of my big blocks to confirm the size of that lock nut holding the spring and spraybar, as well as confirm if the same as the smaller engines.
As for that O-ring, I use a standard T-pin. Just be careful not to scratch the brass. Most of the ones I've done are pretty brittle so break into small pieces. As with using a filter to prevent any contamination, you want to ensure anything is flushed out before reassembly.
Inserting is where you will have the most fun. I found a small diameter wire inserted in the hole to allow the O-ring to slide down one of the easiest methods. Then carefuly push it into place, (again, trying to prevent scratching or damage to the O-ring.
I would have to pull one of my big blocks to confirm the size of that lock nut holding the spring and spraybar, as well as confirm if the same as the smaller engines.
As for that O-ring, I use a standard T-pin. Just be careful not to scratch the brass. Most of the ones I've done are pretty brittle so break into small pieces. As with using a filter to prevent any contamination, you want to ensure anything is flushed out before reassembly.
Inserting is where you will have the most fun. I found a small diameter wire inserted in the hole to allow the O-ring to slide down one of the easiest methods. Then carefuly push it into place, (again, trying to prevent scratching or damage to the O-ring.
Thanks, Cougar!
P.s. I just realised I have a NIB Saito FA-150 (BK?) to check the spray bar O-rings!
02-19-2026 | 02:02 AM
Cats eye needs to be upward facing. Here's a 220 carb spraybar. There is no O ring except in the end of the spraybar and the joint you'relooking at in the image. Also the LS sleeve O ring. (I think) The very thin O ring that is part of the smaller carbs is not papart of the big block carbs.
Saito 150 carb set.
The thin O ring is not part of the big block carb kits.
Saito 150 carb set.
The thin O ring is not part of the big block carb kits.
Last edited by 1200SportsterRider; 02-19-2026 at 03:18 AM.
02-19-2026 | 08:09 AM
I changed the throttle linkage on the LT 40 by making another short throttle offset for the FG 11 carb. I also swapped in an 8oz tank inlieu of the 10 OZ tank. It's plenty of fuelfor the FG 11 and made more room for the switch and the wiring.
Previous
8 oz tank
All set up except balancing
Turbo Header for Saito 65 with adapter. and new linkage for throttle.
Previous
8 oz tank
All set up except balancing
Turbo Header for Saito 65 with adapter. and new linkage for throttle.
Last edited by 1200SportsterRider; 02-19-2026 at 08:15 AM. Reason: Add images
02-19-2026 | 12:03 PM
Cats eye needs to be upward facing. Here's a 220 carb spraybar. There is no O ring except in the end of the spraybar and the joint you'relooking at in the image. Also the LS sleeve O ring. (I think) The very thin O ring that is part of the smaller carbs is not papart of the big block carbs.
Saito 150 carb set.
The thin O ring is not part of the big block carb kits.
Saito 150 carb set.
The thin O ring is not part of the big block carb kits.
This helps! It seems there have been some changes over time on what items the O-ring kits include. But with the great help in this forum I'm sure I can manage in rebuilding the carb. I'll let you know how it goes.
02-23-2026 | 08:31 AM
Ignition and rcvr batteries mounted for perfect on the LT 40 balance with the Saito FG 11 in front.
The green JR Propo works perfectly, the batteries are removeable with 4 screws in servo mount gromets.
The green JR Propo works perfectly, the batteries are removeable with 4 screws in servo mount gromets.
02-23-2026 | 03:36 PM
Senior Member
My Feedback: (3)
I'm trying to check balance on the P-47, confirming at least which of 2 bays I can use for the servos and other systems. I was hoping to possibly limit myself to the one 2500 MAh LiFE pack for both flight and onboard glow, but I may have to add a second to balance. That Saito 100 simply isn't that heavy and would hate now the tank installation is complete to install one of my 125s in a plane that hopefully remains under 12 lbs total.
Will have to take another pic since at this point only have one of an empty mount.
Another issue is I could have guaranteed I had a 90 degree exhaust fitting to try and keep the muffler and pipe within the cowl, but it is MIA, perhaps used for another ap since this one has been hanging in the build room for far too long.
Anyone have a spare Saito or Performance Specialties adapter gathering dust?
Finally, a question that, since this uses one of my over half dozen 100s, I feel I should know the answer: This one has a large diameter cowl and my standard 13/8 prop is a bit skimpy on clearance. Book states I can go as high as 15/8, but over the years have found Saito was always a bit aggressive in their recommendations and a bit too early yet to crawl out in the snow to test it out on the stand. Anyone have experience turning one that big?
Will have to take another pic since at this point only have one of an empty mount.
Another issue is I could have guaranteed I had a 90 degree exhaust fitting to try and keep the muffler and pipe within the cowl, but it is MIA, perhaps used for another ap since this one has been hanging in the build room for far too long.
Anyone have a spare Saito or Performance Specialties adapter gathering dust?
Finally, a question that, since this uses one of my over half dozen 100s, I feel I should know the answer: This one has a large diameter cowl and my standard 13/8 prop is a bit skimpy on clearance. Book states I can go as high as 15/8, but over the years have found Saito was always a bit aggressive in their recommendations and a bit too early yet to crawl out in the snow to test it out on the stand. Anyone have experience turning one that big?
03-06-2026 | 02:05 AM
Yep, I have one.
(Quote): Anyone have a spare Saito or Performance Specialties adapter gathering dust?
Let me look, you're speaking 12mm correct?
Last edited by 1200SportsterRider; 03-06-2026 at 04:02 AM. Reason: Add content
03-06-2026 | 06:12 AM
Senior Member
My Feedback: (3)
That's what's specced out for the 100.
I have been a bit busy, so much that I fried one of my onboard glow drivers trying to bypass the Rx for power.
Anyway, decided to up the power rather than add useless weight so the 125 is a direct fit. Case and bolt spacing, as well as drive washer distance. are identical to the 100 so it was a no brainer.
That one I have an adapter for, but with all my 100s I would most likely need one in the future.
You planning to go to Toledo? At this point was planning to go Friday and am getting a fuel order together, but not sure if anyone else can make that day.
I have been a bit busy, so much that I fried one of my onboard glow drivers trying to bypass the Rx for power.
Anyway, decided to up the power rather than add useless weight so the 125 is a direct fit. Case and bolt spacing, as well as drive washer distance. are identical to the 100 so it was a no brainer.
That one I have an adapter for, but with all my 100s I would most likely need one in the future.
You planning to go to Toledo? At this point was planning to go Friday and am getting a fuel order together, but not sure if anyone else can make that day.
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AeroFinn (03-20-2026)
