CRAZYRYAN

My Feedback: (1)

im having a bit of a problem in starting my magnum .91 four stroke right now it is cold outside so i thought i lean out both the high and low speed needles to make the engine warm better while at idle, its a brand new engine im just breaking it in and having difficulty in starting it all the lines are in the right place although i noticed there is a third nipple on the intake pipe from the carb. why would that be there? in the intruction manuel and also my older .91 magnum does not have a third nipple. thanks for the help.

delman

When its cold outside the air is more dense - make it a bit richer in stead of lean.

CRAZYRYAN

My Feedback: (1)

well ok but you think also i might need to check the valves? is it a paper thin thickness?

delman

the instructions will give the specs in thousenths of an inch or mm - need to really use a feeler gauge - try richening it up first

w8ye

My Feedback: (16)

Set valve clearance .002" to .004"

CRAZYRYAN

My Feedback: (1)

ok where can i buy a gauge that will work for the small measurments? does tower have them?

w8ye

My Feedback: (16)

You can get the thickness gauges at most auto stores as well as Sears.

Both Tower and Horizon sell valve adjustment kits for their engines. I use these on my Magnum engines at one home. At my other home I use the Sears tools.

Enjoy,

Jim

Flyboy Dave

My Feedback: (21)

The low speed needles on my Magnum 91's set like this, with about 5 threads
showing on the adjustment screws.

FBD.

w8ye

My Feedback: (16)

The low speed screw on my Magnum 91 looks about the same best I can tell.

CRAZYRYAN

My Feedback: (1)

alright thanks a lot

jlobster88

My Feedback: (1)

I just bought the Magnmum .91 4-stroke and was having trouble breaking it in (it would start but ran ****ty, i just kept on running it and had to change the glow plug but now it runs awsome). Someone on RCU mentioned to check the valve clearance, i looked in the manual and couldn't find the measurments ANYPLACE, so if you look in the manual and can't find these measurments don't feel bad.

CRAZYRYAN

My Feedback: (1)

hey man! your intructions sure did help my engine!!! it can now run from idle to full power without dieing out. i finally got it. only bad thing is i just knocked my lading gear along with the whole piece of wood wich came out clean and that means i need to reinforce in that area. also my elecator came lose.[:@] but all is good thanks so much for the adice i got to taxi it in my back yard acre.

TOMAPOWA

My Feedback: (1)

AS SOMEONE HAD ALREADY MENTIONED,...
DOES ANY ONE KNOW WHAT THE THIRD NIPPLE IS FOR, MOUNTED ON THE SIDE OF THE MAGNUM 91 FSR INTAKE PIPE !!!????

DO I NEED TO BLOCK THIS ????????????

THEY DO NOT MENTION THIS NIPPLE ANY WHERE IN THE MANUAL OR WEBPAGES I HAD SEARCHED!

HELP !!!!!!!!!!!!!!

2slow2matter

My Feedback: (1)

That third nipple is for crankcase ventilation. As the piston travels down, the compressed air must go somewhere, ,so it goes out that third nipple. There is also a good bit of oil, and some unburnt fuel (not much fuel) left in the blowby, so that gets recycled back through the engine again--hence, the thrid nipple is attached to a nipple on the intake manifold via some fuel tubing. Not all four strokes do this with their vents, but magnum does.

Also, magnum officially recommends .04 to .1 on their valve clearances, ,but I too use the tools that come with the saito's.

carrellh

A short length of fuel line runs from this nipple to one at the front of the engine near the pushrod tubes
Here's a link to an OS engine with the same setup
http://www.osengines.com/engines/osmg0872.html

TOMAPOWA

My Feedback: (1)

Wow... thanks. I was thinking that. Very weird they (Magnum) never mentioned this...
Funny, I already have the crankcase vent hooked up (via tubing) to exit outside the bottom of the cowl.
I guess I now don't need this.

rustleruss

My Feedback: (3)

Thats funny TOMAPOWA because should i say (Quote from magum) Cranckase Breather: Fuel line can be attached to the nipple on the
crankcase, and Expelled Lubricants Can Then Be Directed Out Of
The Cowling.
Mine says that glad i read you post then the manul before i installed the engine now we do know lol lol j/k

w8ye

My Feedback: (16)

The ASP/Magnum/SC engines did this as a on-going change without a change in model number. It was never mentioed in the manual and the tubing comes in the box but its not hooked up to the nipples.

Enjoy,

Jim

2slow2matter

My Feedback: (1)

hook the tubing up--you won't be sorry. It takes care of a lot of mess on the bottom of your plane. Plus, the intake is engineered to deal with this upstream infusion of air. I don't know how it would run without it--you'd probably have to lean the carb out a little. My 91's run like a champ with it hooked up (I have two of these).

wcmorrison

My Feedback: (2)

Thats odd, because my Magnum 91 came with the tube hooked up. But still it should be a no brainer.

Kinda reminds me of my jet jock buddy, he could fly fighters, real ones, but did not have clue as to how they worked. He learned his instructions to the tee, used the approved checklist and did what the instructor told him to do. Flew like a champ but never did understand how a jet engine worked or for that matter, why it worked. He was a great student.

Cheers,

Chip

Ed_Moorman

My Feedback: (1)

I don't know where he went to military pilot training, but when I went and when I instructed, the students flew a half day and went to academics a half day. There were classes on engines, avionics, the electrical system, hydraulics, everything on an airplane. They are taught basic aerodynamics, weather and are tested on everything. The academic grades counted half of your class standing from which you could choose your initial aircraft assignment. Maybe he did a data dump after getting his wings.