1936 Indian Junior Scout

[Clark58mx]

Hello I just joined the AMCA. I bought this 36 Indian Junior Scout back in May. It was fairly complete. I finished it up a couple weeks ago. I was told it hadn’t run for many years(45+). I got it running, and it starts easily. The question I have is about the Carb. It’s a Linkert M541. I bought it NOS. I was told it’s not correct, but the bike will perform better. The problem I’m having is that when the throttle is applied, I’m getting a fuel mist coming out of it. I’ve played around with the High/Low needles and float Height. Any suggestions?

[T. Cotten]

Hello I just the AMCA. I bought this 36 Indian Junior Scout back in May. It was fairly complete. I finished it up a couple weeks ago. I was told it hadn’t run for many years(45+). I got it running, and it starts easily. The question I have is about the Carb. It’s a Linkert M541. I bought it NOS. I was told it’s not correct, but the bike will perform better. The problem I’m having is that when the throttle is applied, I’m getting a fuel mist coming out of it. I’ve played around with the High/Low needles and float Height. Any suggestions?

Welcome, Clark!

Scheblers got a bad reputation not because of their "performance", but their deterioration after the fact.
I doubt you could tell much difference if you had a properly re-conditioned DLX112 on it, if all other things are in order.

Ordinarily there is only one float setting for a common Linkert: ¼".
However, I have a factory spec sheet for another 30.50", the M-741, that enigmatically cites 7/16"!
Assuming your float is of the proper buoyancy, I would stick with ¼", and perform other diagnostics before experimenting.

The primary diagnostic before all others is a simple bubble-test of the manifold assembly, as discussed at http://virtualindian.org/11techleaktest.html.
If you do not get bubbles with a constant, regulated air supply at ~15psi, we can go on to other things.

Good luck!

....Cotten
PS: If your M541 was truly NOS, it would not be bare bronze, but have "aluminum" lacquer on the body.

[Clark58mx]

Thanks for the info. I have the float set at a 1/4”. That link about the manifold leak was very helpful. The bike almost always starts first or second kick(cold or hot). I’ll work on the manifold. I have the high speed needle set at a 1/2” turn out. The low speed is set at 2 turns out. The low speed doesn’t seem to do much.

[T. Cotten]

Clark!

I would expect the HS needle to be closer to 1½ turns out, and the LS to be 3½ or so.
The lowspeed is ordinarily the more sensitive needle, as the HS can only be adjusted over 30 mph or so.

If your carb was "NOS", did you find a cork float? Was it ¼" to begin with?
(If its cork, it should do fine for a while, until modern fuels affect it.)

....Cotten

[Clark58mx]

It has a plastic or nitrophyl float. I bought this Carb off of EBay. It came from a shop in Vermont. I’ve been going by the Linkert carb Adjustment page on Kiwi Indian. The high speed needle is the one near the choke lever(left side) right? Because that is the only that affects the way it runs. The plugs look normal.

[T. Cotten]

Clark!

You probably have a Rubber Ducky float which should be fine (until you hit the wrong gas pump.)
Beware of some "nitrophyl" floats with an integral screw molded into them. They weigh three times as much, and handle modern fuels poorly too.

And yes, the HS is on the chokelever side.
If the LS has no effect, you may want to inspect its assembly closer. Please be certain that the lift lever spring collar is in place (with the 'top hat' portion upward into the spring), and that the needle is below the spring within the knob, and not on top of it.

Once again, the LS controls at idle and low speeds, and the HS should have little effect (unless completely closed) until going fast enough for the venturi circuit to kick in.

....Cotten

[Clark58mx]

Ok I’ll check the low speed and how it’s assembled. Something isn’t right with it.

[Clark58mx]

I started the bike up. I had the low speed 4 turns out and it ran. Then while running, I turned the low speed in all the way. And the bike still ran. Made no difference. But the bike won’t start, unless the high speed Is a 1/2 turn out.

[T. Cotten]

Clark!

It makes perfect sense that the HS must be open some, as all fuel is metered by it.
The LS only meters fuel into the idle circuit (and then air to the main nozzle after the venturi "kicks in", and the idle circuit reverses itself.)

To be able to turn the LS all the way in brings back up its assembly within the knob.
Your LS needle when removed from the knob should be 3 1/8" long.

The needle goes into the knob before the spring.

But no matter what, the manifold needs to be proven secure.

....Cotten

[Clark58mx]

Ok i measured the needle. It’s 3 1/8”. And it was in first, before spring.

[someozybloke]

Fuel mist coming out of the air cleaner opening, could it be an issue with the main nozzle facing the wrong direction.

[RykerRacing]

The valves not seating due to being worn out or a poor valve job or tight valve lash, also over retarded ignition timing could spit or mist gas out the carb as well. Once you verify everything there is good then start looking at the carb. The 541 carb is fine application wise, the 5 stands for junior scout and 41 is the year that is why they tell you it isnt the right carb for your 36.