BobH

My Feedback: (2)

FYI I happen to have an UMS 777 radial that was barely used. I bought a new carb (OS) for it and never put it on.
I think It'll perform much better with the OS carb.
Contact me if interested.

georgek_54

Hi all
I bought a new SAITO FA 120 R3 as my first multicylinder engine. Trying to break-in the engine on the bench (according the instrucrions) I noticed that engine's rpm do not change at all by the needle valve. Even if I unscrew it by 6 or 7 (!) turns the rpm remains the same, about 7400 (throttle fully open). So I can not have the engine working with a rich mixture as needed during break-in. After only 1,5-2 minutes the engine becomes also very hot, the metals of the engine smell, so I stop it immediately. Very often one or more cylinders go out of function, but I accept it, as the engine is still new.

What worries me most of all is that the rpm remains the same with all needle-valve adjustments. It alters only with throttle. I checked the tank for any leaks and it is O.K. The muffler is that provided by the factory, i.e. 3 tubes.

The matter is really very disappointing to me and I would appreciate any help.

Thanks

George

Maxam

My Feedback: (62)

George, first off, the small Saito's lack appreciable torque. Use a 13x7 or 14x6 prop. Now in a quiet room, attach fuel line to the carb so you can blow through it. Screw the needle valve down to off and gradually unscrew it. By 1 turn you should be able to hear air flowing through the carb (if you have good hearing) and more as you unscrew. A design issue with Saito carbs is if the idle screw is in too far you also cannot richen the high speed needle. So try to open the idle needle a turn if the high speed needle lacks flow. The small Saito radials, 90r3 and 120 r3 are durable long lasting engines. My 90r3 has outlasted three airframes!! -Tom
When you do these tests, make sure the carb throttle setting is all the way open.

georgek_54

Thanks a lot, I will try this asap and let you know again. I am using a 14x6 propeller.

When I screw the needle less than 2 turn the engine stops. It seems that the mixture is very poor and the engine "understand" this, it can not work with such a poor mixture. The contrary is not working: By unscrewing the needle, the engine "does not understand" that the mixture is (?) rich. But I will try tomorrow the idle screw (here is already night).

georgek_54

Yes, it worked Tom, I am so grateful!

I had to open the idle screw by about 3 turns. The rpm adjustment range is not enormous using the needle valve- from about 6800 to 9500 rpm- but at least I know now that I can enrich the engine so that I can break it in correctly. I think 9500 rpm with a 14x6 prop is very satisfactory.

I am going to install this engine to a Seagull P-47 THUNDERBOLT "SNAFU" which I bought specially for this engine. It would be a great dissapointment if the engine could not work.

I think that with a 14x6 prop and 9500 rmp this model will fly well.

Thanks

George

Maxam

My Feedback: (62)

Glad to hear it George! -Tom

Hyjinx

Looks like this thread has gotten stale.
I am about to sell off a few of my radial engines.
Anybody still watching this forum?
Aaron-(Hyjinx) premium member

RichardGee

My Feedback: (156)

I still received notifications when someone posts.
I have two Saito FG-60R3's en route to me now from Horizon Hobbies. These engines were on back-order for several months.
These will power my second Grumman XF5F Skyrocket project.
RADIALS RULE.

RadialWacko

the ums engine care thread is going strong.

Rv7garage

My Feedback: (10)

Still here!

redball8

My Feedback: (128)

Me too ...

cymaz

I’m here!

harriermate

And me!
just been looking at buying a radial for my ‘almost complete’ Flair Stearman. Toying with either the UMS 7-77 glow or the same size 7-90 petrol. Not sure of the advantage of either… both are much larger and heavier than the Laser 200 recommended! I’m guessing additional LiPo needed for either to fire the glow plugs on board or power the spark ignition system???

Hyjinx

I have a low documented run time Evo 7-77 that starts easy with a external 1.5 v battery pack. Runs and idles without the pack once started on 15% nitro 18% klotz T Plate. 800 cash. Located in Chelsea Michigan 48118.

Currently mounted on a Tony Eck built BUSA Newport 28. Ready to fly. 1200 cash. Never opened to inspect. Stored indoors in a climate controlled finished basement.
[email protected]

Hinckley Bill

My Feedback: (568)

Lurking in the shadows.....great thread, lots of information

redball8

My Feedback: (128)

You run 15% nitro and 18% synthetic in your Evo 777? Heck, I run 5% nitro and 6% lube (11% of which is castor). It’s an earlier UMS/Seidel 770, but basically the same engine, just not bored out. That’s what the manufacturer (UMS) recommends. Buy yourself some pump methanol at a little over $3/gallon, and you can cut your fuel bill in third!

Hyjinx

QUOTE I have 11 radial engines and 15 or more singles. I have never replaced a bearing All my glow engines start, run and idle without on board glow drivers.
I am very happy with the fuel I mix. If you buy any of them. I would highly recommend my fuel mix.
Aaron-

redball8

My Feedback: (128)

My apologies, Hyjinx, I didn't mean to be judgmental.

Maxam had turned me on to Jackson Solvents in Indianapolis; they sell pump methanol to the karting/Sprint racing community. I've family that way, and every now and then bring about 30 empty fuel jugs and fill them up. I blend my glow fuel per Gierke's recommendations, though these radials use much less oil than he recommended. I've had my 770 since 2013 and it too runs very well on the low oil fuel. Given how expensive glow fuel is these days, if you have access to bulk methanol, it can save some $$$!

Hyjinx

No offense taken.
I consider fuel and oil additives a small price to pay for my hobby. I pay a local auto parts store 55.00 dollars a five for VP methanol. I pay a local power sports store 22.00 (I think) for quarts of Klotz Technaplate. I pay my local hobby shop 65.00 dollars for two gallons of 30 percent Morgan heli fuel (it contains combustible Mineral based oil that is real smoky and mixes well with the Klotz. I sometimes add straight castor from the lhs but not always.
I buy Amsoil from a auto parts store 1.5 hours from my home and mix it with rec fuel from my local gas station. I don't care what any of all of that stuff costs or how far I have to drive to get it. Even with Biflation and the decimation of oil company profits due to his administration.
​​​​​​ No offence intended, none taken.
Aaron Hubbard
Chelsea
Michigan
USA
Further more. I try to remember to pray for my elected officials no matter what they stand for. I hope our nation does the same.
And I hope we all vote for the candidates we believe will lead our great nation into the future. Whoever they are based on personal choices made by the citizenry of our sovereign Republic of States.
Please any and all typographical errors.

Walther

My Feedback: (1)

I purchased a used one that the sell said it had the English mods. Is there a way to tell with out tearing it down?

Hyjinx

Ask for the invoice from Ray with the serial number of the engine before you buy.
He doesn't modify engines for free.