Hi guys,

I just got my first 4 stroke from the big brown truck, and I could use some help. It is the Magnum .91. THere is a fuel line on it that is running from just behind the front of the motor to the pipes running up from the carb. Then there is the fuel intake nipple on the carb itself. is that the way it is supposed to be? is there pressure that runs to the muffler?

I am going to run 30% heli through it and run it in tomorrow. Any help would be greatly appreciated.


Sorry I don't know the names to everything yet, still learning.

Tom

The line from the front of the motor is a crankcase vent. The line sounds like it is going to the intake, which puts the crankcase drain into yhr intake. This is normal. If there is a nipple on the muffler then this is the pressure. The nipple on the carb is the fuel one.

Cheers.

Got Magnum 52 and 120 FS, both have pressure nipples on the muffler as Ghost suggests. Unlikely the 91 would be different.

Not sure why you would use 30% fuel with this though, 5 - 10% should be plenty.


Terry

Any fuel beyond 20% nitro is a waste of time on this engine.

The Saito's will respond to 30% but the OS and Magnum engine show little improvement beyond 20%.

Enjoy,

Jim

I like the oil content which I am told (engine experts set me right please) should be a touch higher to ensure engine life. Plus the diff price wise is only 5 bucks a gallon at my LHS, so why not?

I know that OS recommends that you do NOT use a hight oil content in their 4-strokes - 16 to 18%

Not sure about Magnum

I use Cool Power 15% in all my engines (OS, Saito, and if I had a Magnum, I'd run it in that too)

Hmmm, ok so once again not sure what to think. I would consult the directions, but they are all in Chinese, which I don't read. I will try and find some online source. Thanks guys for all the help.

Tom

i have a mag .61 f stroke

i run cool power 15%
+ i add 2 / 2.5 oz of castor
what the castor does is it makes the oil content 20%
which is recomendedby certain mfg except o.s.
8/9 bucks for a bottle of castor is just a litle piece of mind


and i also run the same fuel in my saito fa .82 f stroke
no problems so far after 5/6 gallons...

Follow the Ghost. I have 4 Magnum .91 four strokes and use 15% nitro with 20% oil (Ritches Brew). I use this on all my 2 strokes also. Saito advised me on this fuel some time ago for my Saito 65 and I went with it on everything and have always been happy with the results. The nipple on the crankcase is connected to the fuel intake manifold pipe above the carb with the small flexible tubing included. The nipple on the muffler is for the pressure line to the tank. The nipple on the carb just above the needle valve is the fuel inlet from the tank.

I wouldn't run more than 20% nitro on it. Why waste the extra money on the expensive 30% heli. Mine runs great on 10%. Plus cheap.

Good luck

my o.s .52 fs surpass runs just fine on byrons 10 % nitro and 16% oil ....... as far as engine life goes , i run this thing pretty hard on that fuel and have had it a year and a half. it still runs like i just took it out of the box

Excellent help guys, thank you very much for all of the replies.