Michaelh

My Feedback: (4)

ok I was saying how great my 82's were

ILv2Xlr8

I experienced the same thing with an old 72 that seized up right after 10 min on its first run. The crankshaft had a burr on it that binded the piston connecting rod to the crankshaft. It also appears the end of the crankshaft was rubbing up against the plastic back plate.

I wonder how many of the early 72s had this problem?

PacificNWSkyPilot

My Feedback: (19)

50 RPM? I'm gonna guess your multiplier was off, and say you were at 500 RPM.

Jim

rustypep

My Feedback: (6)

Saito 100. I guess I left out the important part .

w8ye

My Feedback: (16)

From Seany Chin
Powermaster 20/20 fuel
Master Airscrew 14x7 3-blade = 9500 rpm
Graupner 14x7 3-blade = 8700 rpm
Master Airscrew 14x7 Scimitar 2-blade @ 10100 peak

paul49

Hi All,

After flying two-strokes for some time, I decided to try a four-stroke earlier this year. Settled on an FA-82a to power a CMPro Edge 540. I received some excellent advice about break-in in other threads but I've just realised that I hadn't posted here yet. So just thought I'd say "Hello".

Haven't had a lot of time to fly the Saito but took it to the field on Saturday and ran about half a gallon through it. I originally had some trouble getting it to idle slowly enough to land, but, as was suggested, a few flights have improved it considerably.

I was expecting it to have more torque than my two-strokes but I'd have to say that the difference is astonishing. It takes off in about 10 feet on half-throttle and the take-off roll is almost non-existent at full throttle. I'm impressed! And the guys in the club tell me that it will just keep getting better as I fly it. It's easy to see why people like Saitos so much.

As I said, it's idling pretty well now and will go straight to full throttle with no hesitation. But I did notice that it has now become a tiny bit uneven in the first third of throttle travel. It's not enough to cause any problems, but should I be tweaking the needles this early in its life or just fly a couple more gallons through it and adjust them then? It's been run for 20-30 minutes on the ground as per the manual and then about 2/3 of a gallon in the air.

Cheers,
Paul.

Rudolph Hart

Good one mate

Rudolph Hart

Hi and yes 500 sounds better,good transition? as i'm going down the same road,150 size scale models need an fg 36 gas motor.

PacificNWSkyPilot

My Feedback: (19)

Paul49,

You've had it running plenty long to start tweaking your needles. If it's starting to get a little funny in the first third I'd trim down your top end needle a little bit, say, about a 1/4-turn for starters (you're starting to need it less rich all-over), and then start turning your idle mixture screw in and testing the response from idle and up through transition.

Remember to carefully count your turns and write them down first before you ever start it. It's always good to be able to go back to a place where you know you were okay. Then keep track of the turns as you go. I think you may be surprised how different they'll be set now that you've done a good job of breaking it in.

Jim

PacificNWSkyPilot

My Feedback: (19)

The Saito manual says it requires a 20% oil content that is not entirely castor if possible. I use the Powermaster 20/20 blend for Saitos and YS. Mine is a little higher nitro content than they recommend, but the motor seems to love the fuel. It didn't love the 15/18 4-stroke Wildcat I had previously used for my older Saitos, but I'm thinking that might have been that it was tight during the break-in period. Still, it responded to the 20/20 right away and ran great.

I can feel the difference after just about 6 tanks now, it's running strong, has higher RPMs and idles like a bear. Don't ask me how a bear sounds when it idles or I'll have to get into sound effects!

Jim

Hobbsy

My Feedback: (102)

Paul, I like to use easily remembered and repeatable methods of doing things, I use this to get the 40 minutes run in time recommended by Saito.
10 minutes at 4,000 rpm
10 minutes at 5,000 rpm
10 minutes at 6,000 rpm
refill fuel tank on test stand
10 minutes at 7,000 with short runs to peak
Next set HS needle at absolute peak, (temporarily)
Now procede to lean LS needle 1/8th turn at a time checking transition and peak after every other change, at some point one of the 1/8th turns will make more difference than the previous ones. You're getting close, now, find the best transition being willing to settle for a slightly higher idle rpm if that's what it takes to get the best transition. The best idle and transition usually go hand in hand but not always. Now richen top rpm down about 200 and go fly. Sometimes a lousy fuel tank location requires a richer HS needle to avoid leaning near the end of the fuel supply.

Hobbsy

My Feedback: (102)

Saito .80 and TurboHeader

Old High compression Saito .80, 20 or so years old
Fuel===WildCat 15% Premium Extra
Plug===Fox Miracle
Prop===Bolly 13.5x6
RPM with new style cast muffler============10,150

RPM with new style welded TurboHeader/baffle==10,351

As you can see the engine is quite skinned up but runs like a Swiss watch.

nashtm

Hi

I have an inverted 125 and was using an on board glow system but the back fires on start up were so bad and often that I start using a normal glow driver which has helped tremendously (but I still dare not prime it or flip the prop before applying the starter).

Has any one else found an on board glow (with current sensing) to be problematic with an inverted motor ?
Is there anything else one can do prevent/minimise backfires on start up ?

Thanks
Tim

JNorton

My Feedback: (2)

I've never had to use an on board glow system because the motor's inverted on ether a 2 or 4 stroke.

Is your tank level with the carb barrel? I used a dremel with a sanding drum to modify the formers so the tank would fit properly.
John

ram3500-RCU

My Feedback: (221)

I agree. My feeling is that a correctly tuned engine, with a properly installed fuel system, and a good glow plug, needs no "crutch" like an on board glow. As noted, make sure your fuel system isn't siphoning to the carb on it's own. A loop in the fuel line which takes it above the carb is sometimes helpful. This is assuming that the valves are in adjustment and no one has fooled with the timing.

ram3500-RCU

My Feedback: (221)

How about the sound?

Hobbsy

My Feedback: (102)

The sound is deeper and more authoritative but not louder.

PacificNWSkyPilot

My Feedback: (19)

Actually, when I invert a Saito I use on-board glow for idle dependability and low-end as well.

That being said, kicking back on a Saito says to me loud and clear....TOO RICH. A big Saito like that being set too rich means cuts and bruises and banged fingers. Drove me crazy until I figured that out. I almost threw away a Saito 150 from that.

Also, make sure you don't have any spring-loaded fuelers with that, you'll have to set it too rich. Use a positive-seal plug in your fueler. Too much vacuum in a Saito, they can pull air right into some of those spring-loaded dots. You tune (richen) to compensate, and things just get crazy from there.

Jim

BChris

Hello everyone. Y'all seem to be a very helpful group, so I am hoping you can help me out. I have an older FA91 that was running pretty good, had a small crash no noticable damage. The first flight after plane repair was great, engine was awesome. Second flight, not so good. The engine runs good up to about 1/3 throttle after that it starts leaning out really bad. I replaced all the fuel lines and checked the tank and everything seems good. I tried to run it again and ended up backing the needle valve all the way out and it was still lean on the high end. Any help would be greatly appreciated. This is my first Saito by the way. It was great up till now.

Brad

ram3500-RCU

My Feedback: (221)

Sounds like dirt in there. Could have worked its way into a bad spot during that first flight after the crash. I would take the needle assembly completely apart and clean throughly on a clean white cloth so you can see what comes out. Add a fuel filter to the supply line for awhile, and see if you catch anything. Normally, I don't like on-board filters and prefer to filter the fuel as I load it so as to keep the system clean.

Michaelh

My Feedback: (4)

Paul , with my experience with the .82's you can expect around a 600-800 rpm gain from initial break in to full break in (on 15%). You'll notice your low end is going to richen up as it breaks in also
the low end will just keep getting better and better . My initial low end rpm's are about 2700 at first and I settle to 2000 , although I can go lower this seems to be the best all around
idle rpm to me .

w8ye

My Feedback: (16)

The low speed needle is in too far

Michaelh

My Feedback: (4)

No need for onboard IMO . I run all inverted setups and a reliable idle is had with proper tuning.
Even a heavily oiled 30% will see a reliable idle with the right tuning inverted .

PacificNWSkyPilot

My Feedback: (19)

Bchris,
Is your fuel system sealed, or are you using a fueler like a dot?
Jim

nashtm

The on board glow is not stricly needed - it just allows the motor idle slower.
I will look at tank height also my fuel line makes a slight loop below the carb ,not above, maybe lifting it will help.
BTW the motor has about a gallon through it - I have leaned the low end till it wants to back fire on throttle up so I dont think that I am too rich on the low end.
Apart from the back fires I much prefere the 4 stroke to 2 strokes !

Thanks
Tim