View Full Version : First start 41 scout this weekend... or at least a try

01-18-2014, 08:05 PM
Going to try and start the bike sunday any pre-flight rituals that people have?

I watched a few videos on line but not very detailed

Spark advance full
Throttle 1/2
Choke one click on?
three kicks
then turn ignition switch on tank on? what position does this go as mine is not marked? one, two or three clicks to the right?
Kick and start right?

any advice is more than welcome!

Tom Lovejoy
01-18-2014, 10:03 PM
Spark advance is retarded to start - less likely to kick back that way. Once it fires advance spark , should be one click to the right on the switch, give it two good kicks full throtle, choke full closed. Then about half or less, choke open to second notch or so, turn the ignition on and go, don't forget to turn the gas on. It don't hurt to have a fire extinguisher standing by - good luck!!! Right on and have fun !

Tom Lovejoy
01-18-2014, 10:05 PM
Clear that wording up a bit, prime with key in off position.

01-18-2014, 11:51 PM
Clear that wording up a bit, prime with key in off position.

And gas off while priming? My BMW I prime with gas on then kick with ignition. Just curious....

01-18-2014, 11:54 PM
Gas on while priming. If you follow Tom's advice and all is right with your sickle, it outta fire right up.

Oh, yeah don't forget to open the choke all the way after it's warmed up a bit!

01-20-2014, 12:35 AM
For the first time in 9 years she is alive!!!

Melted the spark plug wires, damn!! but she ran!!! Thanks for the advice!!


01-21-2014, 12:53 AM
Melted the wires built all new set copper core

She fires but dies after idle for a few minutes? Dies quickly? Carb float?

Tom Lovejoy
01-21-2014, 01:15 AM
Right on! well done! sounds good too, check your gas cap - make sure the vent is open. leave it loose and see if that makes a difference -If clogged, they will die like that. Check the gas flow from you pet cock/ tank to carb. Check float level, doe's it idle ok? You'll git it, hang in there - you'll be riding in no time!

01-21-2014, 11:03 AM
Right on! well done! sounds good too, check your gas cap - make sure the vent is open. leave it loose and see if that makes a difference -If clogged, they will die like that. Check the gas flow from you pet cock/ tank to carb. Check float level, doe's it idle ok? You'll git it, hang in there - you'll be riding in no time!

Thanks I'll try the caps... Got lots of gas.... Wondering if I damaged the could at when the plug wires melted it shorted to the heads?

01-21-2014, 07:02 PM
Ok fuel caps loose fired up two kicks idles fast

As I play with the throttle and spark advance it backfires and dies out. I can seem to be throttle down without spark advance full? i.e is I rotate both wrist in it should speed up both out it should idle slow right?

Seems to be lots of gas "splashing" out the carb as well. I set the high speed idle 1-1/2 turns out and the low speed idle 4 turns out per the riders book as a starting point.


01-22-2014, 12:29 AM
Did you dial in your carb after the initial setting to fire it up? Might only need some fine tuning... worst case scenario some carb/manifold work. As Tom said... have you checked the float level? Other than that it sounds like you are well on your way to riding that bike! Gotta love the sound of a flathead!

01-22-2014, 01:19 AM
Cory not yet going to try that next assuming it is running rich at those settings based on riders manual.

01-22-2014, 08:43 PM
Ok let is sore from kicking so I am earning this!!!

I pulled the fast and slow needles they look fine.
I ended up pulling the bowl and no signs of damage.
The shut of needle looks good and the float is brass
I set it at 1/4" from the top of the bowl is that right? I am reading that that may not be right and was for a cork float? shout it shut of lower with the brass float?

I can't get it to stay running unless I advance full on spark and a lot of throttle, even then you see gas coming out the carb throat now? That can't be right?

frustrated !!! :mad: but that's why I bought it;)


Frustrated as I had it running before I melted the wires, I set the carb back to factory preset which are supposed to be rich and made new copper core plug wires

Tom Lovejoy
01-23-2014, 12:57 AM
Your shot's are fun to watch, hang in there. Once its running, should be full advanced, unless your trying to slow it down to the max - which is not good for the engine. Idling to slow, I mean. Always been told, keep it advanced, unless pulling a real hill or something. Then just back off a bit till you feel the engine hit a sweet spot. Not sure about the float level as far as brass, but manual says - 1/4 inch. I don't know, but on mine - I think because of worn parts. I have my needles turned way in. If I remember right my high speed was 3/4 turn out and low speed 2 turns out. With mine turned out like the manual says to start - it was way to rich. I like to run a fan on my engine when I do this work, help keep it from getting to hot. It's kind of tricky, always takes me several attempts to git it the best I can. It sounded like it was idling pretty good I thought, don't think you have intake leaks. Always better a bit rich than to lean, once you git it running the way you like. I would richen it two notches or so on the high speed just to play it safe. As long as your not blowing black smoke or back firing all over the neighborhood :-) Keep at it, usually when I git fed up and am about to throw in the towel, that's when I git it - good luck.

01-23-2014, 01:37 AM
Tom thanks I ordered a new float(rubber duck)and needle/seat. I hear you on idle speed but i can back throttle off at all. Will leave advance on an see if i can dial it in.

01-25-2014, 01:49 AM
If nothing else you are going to know your bike when you get it up to snuff! If you still have problems after the new float and needle fix maybe take us through your procedures and somebody just may be able to walk you through it. The quarter inch thing I think is standard but are you allowing for the slight offset as well? When you said you had it running prior to the wires melting, did you think the carb was set right at that point?

01-25-2014, 02:19 AM

Thanks I agree ;-)

So I got the carb off and was going to send it to V-Twin Mfg Shop in New York but after two phone calls and a few mails they said I needed a dealer to send it in? So I think I'll just rebuilt it myself and order parts from Linkertcarbs.com.

I took it apart and it looks to be in good shape overall but the float was full of gas so I will go with a composite model.

What I can't figure out is if I have the 1 1/4" or 1" model?

The Carb is marked M741-1 and the side of the body has 1 MOD M and 2 5 8 stamped below that.

The kits reference straight inlet threads vs. tapered and Harley vs. Indian and I have the straight threads.

Any thoughts? on the size and how to tell?

T. Cotten
01-25-2014, 11:07 AM

Your carb is nominally a 1" Model.
The -1 means you have a 3/4" venturi instead of a 13/16", by my notes.

If you intend to run the "jeep" filter, you will need a valve with tapered pipe threads (1/8"-NPT). A straight one (7/16"-27) will accept a recut with a common pipe die, as the threads per inch are the same.

Carburetors are quite forgiving, but intake leaks are not.
Please bubble-test as discussed at http://virtualindian.org/11techleaktest.html, and let us know how it goes,


01-25-2014, 11:45 AM
First thanks for all the help you guys Rock!

Thanks for the info so I have the 1" got it
1.What is a "jeep" filter?
2. The inlet I have now has the brass threads that are not NPT but straight pipe this should be fine right if I run an in line filter with hose to each end?
3. Yes I plan to make a plate and bubble test , the float full of gas however is my primary concerns and hopefully some of the problem.

01-25-2014, 12:28 PM
Now that you've got Cotten's attention, all should be well. The bubble test can save a lot of tale chasing. Mind you a float full of gas hasn't been helping you much either. I've not used the "Rubber Ducky's" but can most certainly recommend the floats that Cotten makes.

T. Cotten
01-25-2014, 01:44 PM
C.O. posted: "Now that you've got Cotten's attention, all should be well."

Now Cory,

This one's out of my control, but I'm here to help.

41Indian should be encouraged to tackle his carb for his own reward. I am certain that most individuals are as thorough as the majority of commercial rebuilders.


Just for reference, it would have been produced with "aluminum lacquer" finish upon the body.
(I have observed evidence that the bowl was painted as well in '41.)
The small hardware would have been a mix of cad and nickel.

For general inspection, first look for an 'eyebrow' of wear from the throttledisc into the body bore. It is usually accompanied by a 'key' of wear upon the disc (attached).

Almost everything else is covered in the book.

PS: Folks,
One of the most inscrutable pieces of purportedly "factory" Linkert literature that I have ever been privy to is a blueprint that cites an incredible float setting of 7/16", twice on the sheet.

01-25-2014, 02:19 PM
[QUOTE=T. Cotten;137237]C.O. posted: "Now that you've got Cotten's attention, all should be well."

Now Cory,

This one's out of my control, but I'm here to help.

41Indian should be encouraged to tackle his carb for his own reward. [QUOTE]


He should definitely tackle that carb.... it's just not a bad thing to have your input. Your advice has helped a bike or two of mine run better and I know this Scout owner is going to be stoked when his bike ticks over like an old watch.

T. Cotten
01-25-2014, 03:07 PM

I merely meant that my presence is no guarantee of success.
If only it were,...

Meanwhile, a review of this alleged 'factory' M741 specifications sheet has opened my eyes to mystery after mystery.

The little idle bleed hole to the rear of the carb bore is called the "upper idle hole", and the large hole forward is called the "lower"..


Then: "SLOT.009" gives us no clue as to how the slot was achieved.


Now I must start logging the distances between idle bleed holes?
(There goes another six months of R&D budget.)

And just where is the disc?


Okay, the 'air intake disc' is the chokeplate. But what is the "notch", and how does one get it next to the bowl?

Still just a student of these things,
Thanks in advance for any clues at all,

PS: 41Scout!
Here's what I meant by the 'Jeep" filter; Please contact Robin Markey for correct applications, because I have no clue.

01-25-2014, 04:38 PM
Awesome! Cotten how do I get one of your floats?

T. Cotten
01-25-2014, 05:34 PM

You can always contact me directly at liberty@npoint.net,
but since you have already spent for a RD, you might as well get your mileage out of it.
It will do great until you stop at the wrong gas pump.

I cannot view your photos well, but you do well to get rid of the soft-tipped floatvalve. Any of the metal-needle valves on the market are fine.

Aside from the borewear issue, please inspect for a loose venturi.
After thorough cleaning of body and venturi, install the venturi and hold the assembly up to light, and carefully inspect for daylight around it.

The manuals also do not address distortion of the manifold flange from fastener stress. It is easily dressed upon a flat stone or sheet of stick-on emery upon glass, and the aircleaner flange likes it too.

Your needle points may show blemishes that are easily dressed with a stone, if you have a way to spin it (attached).

Carefull observation will always turn up concerns not covered in the manuals, after seventy years or so.


01-25-2014, 10:20 PM
Cotten et al,

Thanks for the great info and I an definitely a hands on guy and learning about the carb more and more. The confusion was on the various options.

I've cleaned it, the venturi is tight. The throttle plate does not have a key but is stamped with a 12.

High speed needle looks good low speed is grooved and I may just order a fresh one from Linkert.

I'll run rubber ducky for now and set it at 1/4 but saw your note on 7/16 so I'll need to decide I guess.

Did a flat sand on the flanges to get them looking good.

Not using a Jeep filter just an inline for now should be ok?

QUESTION: For the main jet I could not tell which way the holes face when it came out any need for orientation?

T. Cotten
01-26-2014, 08:34 AM

Please set the float at 1/4", as per the military Operation and Maintenance Manual.
You may choose to set it slightly shallower if you choose a fat gasket.
(No gasket was spec'd!)

The 7/16" setting on the blueprint is only one of several enigmatic dimensions, such as rotating the bowl to where the valve is 15/64" from the aircleaner flange. History is full of mysteries.

The spray nozzle need not be indexed, however there is a tradition to aim the holes forward toward the air correction slot in the venturi. Perhaps it was in a TM or a Service Shot.


02-02-2014, 12:38 AM

Carb went back together great all clean no leaks float is working.

I got her running and idling great!

I figured out that since I had the rev's up I was on the fast idle circuit and had to slowly back off the throttle and the spark advance then turn the needle in and repeat to get is stable at slower speeds.

Hope to put her in gear and re-wire my brain in the morning for foot clutch and right hand shift

Thank you guys for all the advice.


02-03-2014, 12:09 AM
Great news!!! How did that ride go?

02-03-2014, 12:11 AM
Didn't get a chance with Superbowl prep

Tom Lovejoy
02-04-2014, 12:38 AM
awesome, sounds good!

02-07-2014, 02:08 AM
Took her for a quick spin!!!

Need to keep working carb, seemed to be powerless and when I stopped gas started pouring out the carb throat while running ;-) WTH!!

Also when I pull in the garage and shut it down and closed the petcocks I heard hissing the gas in the right hand tank was bubbling? Heat from the copper gas tubes? Seems bad as the thing was acting like a gas tea pot


T. Cotten
02-07-2014, 11:35 AM

About the overflow,
When installing your fresh float, did you off-set it within the bowl as shown in the manuals?
And when installing the bowl upon the body, is the valve rotated close to the choke assembly?

It is easiest to determine if the float is hanging up upon the bowlstem by turning the assembled carburetor upside down, and sucking upon the valve.

They can be pesky.


02-07-2014, 12:36 PM

Thank you and yes I offset it and I turned it upside down and "blew" into the port and is seals.

It was weird after a ride up the street I can back and at idle saw it pouring out, engine still running.

BTW any idea what makes the gas Bubble? heat?

I restarted it and it idled fine.

I am not sure what you mean by this?
"And when installing the bowl upon the body, is the valve rotated close to the choke assembly?"

T. Cotten
02-07-2014, 02:26 PM

The position of the bowl affects the clearance of the float over the bowlstem. They often hang up at ninety degrees to the body, but have the most clearance with the valve placed close to the choke.
(The literature I cited previously placed it within a quarter of an inch of the aircleaner flange.)

Back to testing the valve and its position: blowing in it doesn't work.

PS: "Bumping" or flashing of fuel in a tank directly over a hot motor makes me anxious too. But it is less of an immediate safety concern than running with an overflowing carb.

02-07-2014, 03:14 PM

Thanks again

By the valve position I assume you mean when looking face on to the bike and card is the valve inlet assembly to the left and in lien with the choke? If so the answer is yes as shown in this picture.
or should I rotate it more toward the choke lever I.e. more forward toward the cleaner flange?

I inverted the bowl off the carb and the float does not hang and holds pressure when blowing into the inlet, are you saying leave it in the normal orientation and suck on that port to pull the float closed?

I assumed heat was the culprit on the gas line but is there a cure?

T. Cotten
02-07-2014, 04:23 PM

It could probably be rotated a bit more (See attachment).

And blowing into a valve nipple just opens it.

With luck, you should feel a tiny pop when you pull your tonque off of it.

PS: The bare carb in my attachment is an amateurish embarrassment.
It should be "aluminum lacquer" or other silver paint.

02-07-2014, 04:35 PM
Thanks for the photo and I'l try it not sure on the physics of why this matters rotationally but I'll try it ;-)

as for the blow and suck I think we are saying the same thing but I inverted the bowl so the needle is closed and the float is holding it closed i/e/ not hanging on the side of the bowl.

T. Cotten
02-07-2014, 06:10 PM
All that matters, 41Indian,..

..is that the valve shuts absolutely.

(Quite often a needle needs to be seated with a whack of a screwdriver handle, but your flood seems beyond that.)

But still, it's suck, not blow.

(I hope I can post that with impunity.)


Tom Lovejoy
02-08-2014, 12:54 AM
I wonder what's up with the gas, never seen that before. The gas tank/ gas should be pretty cool, I think - some thing is not right. Is the tank hot to the touch? Is your oil returning to the tank? Interested to see what you find is causing this, good luck.

02-09-2014, 11:34 PM
Getting closer.....

Took the carb apart nothing obvious.... holds on suck and blow ;-)

Rotated the bowl toward the choke level on re-install
I can get it to idle well and seems ok on snap of the throttle with backed off spark advance.

I put it in gear and no matter how wide open the throttle she was a MOPED!! meaning no acceleration just a slow puttering

I started messing with the power needed and got it a bit better but acceleration is crap I mean nonexistent? very strong exhaust compression(will check with a gauge next week)
points at 0.020

started raining so I quit but but I assume I need to keep dinking with the high speed needle or should I lower the float setting? currently at 1/4"

No gas flooding out and not bubbling in the tank this time.