NAA Gas Line and Carburater

Michael lacey · Oct 9, 2012

I've cleaned my carb, replaced the inlet nozzle with screen (not sure what its called) the fuel line and sed bowl. Now i cant get gas to actually enter the carb. I've followed the gas an narrowed it down to where the gas line meets the carb. So, this means i am not getting gas from the inlet into the carb bowl. i understand this to be a gravity fed fuel system. Is there somethign i need to do to "start" the suction of gas flow so that it enters the carb? or, does it sound like i have a bad float? when i spray starter fluid into the carb, its starts to turn over but obviously fails (thought this might start the suction of flow).

any input would be appreciated!

Royse · Oct 9, 2012

You could have a stuck float and/or needle valve.
I would try pulling the plug out of the bottom of the carb to see if you're getting fuel through it.
If not, rap on the carb bowl lightly with a hammer handle or screw driver handle in an attempt to free the needle valve.
If you still have gas to it, but not through it, probably time for a cleaning/rebuild.

JCinKY · Oct 9, 2012

Do you have flow out of fuel line itself?

If not, make sure your tank vent is open and sed bowl screen is clear. Another screen inside tank as part of shutoff. Drain and check if needed. Fuel on?

If so, tap carb bowl with hammer HANDLE. May have stuck float needle. If no improvement disassemble carb and make sure float is set correct and needle is free.

-Jeff

Den N Ms · Oct 9, 2012

Michael,Take the plug out of the bottom of the carb,you should have gas flow through the carb.If gas does not run out contentiously it may have trash behind the needle valve stopping the gas flow.

JCinKY · Oct 9, 2012

Man...to slow again. That's two in a row...

Michael lacey · Oct 9, 2012

When i pull the plug, no gas exits the bowl. if i remove the fuel line from the carb, gas pours (very little) from the fuel line. when i took the carb off before, i thought i cleaned everything well. nothing looked bad and i pulled everything out to inspect. looked pretty straight forward as far as putting it back together correctly. after i installed the carb, i even tapped it with a rubber hammer, removed the main adjustment and idle air adjustment needles to see if i could jar something lose.

sounds like i need to repair: the rebuild kit is about $70 for the NAA and a new carb is $290. I'd hate to waste the $70 if i could just buy a new one and know its all put together correctly.

any more thoughts? i've been buying parts from steiner.

Den N Ms · Oct 9, 2012

Michael,Take the carb off then take the bowl off.the float could be bent some and hanging up on the bowl or the needle valve just stuck and no parts needed.

Royse · Oct 9, 2012

(quoted from post at 20:51:41 10/09/12) When i pull the plug, no gas exits the bowl. if i remove the fuel line from the carb, gas pours (very little) from the fuel line. .

You should have a pretty good stream out of that line.
Make sure you are using a vented fuel cap and that it is not plugged.
Take it off for a test.
If there's still no fuel flow, there's the screen in the tank that was also mentioned.
How much gas is in the tank? It needs to be up over the inlet pipe in on the sediment bowl unless you have the valve all the way open.
If you haven't taken the sediment bowl assembly out of the tank, you may want to do that to clean it and the screen.

Michael lacey · Oct 9, 2012

I have replaced the sediment bowl, in its entirety, including the piece that screws up into the gas tank. Heres something i forgot to mention: when i replaced that, i took the glass bowl off first and turned the fuel on. it only dripped out, but quickly and i captured a good bit of it until it stopped dripping. however, i could still see gas in the tank. thinking this might have something to do with the reserve, when i unscrewed the piece of the sed bowl from the gas tank, i expected the balance of fuel to come pouring out - NOTHING.

could i have a clog in the gas tank?

i'll order a new gas cap just to be sure its vented. but yes, i have tried leaving the gas cap off to see if the carb filled up.

Michael lacey · Oct 9, 2012

by the way, I pulled the sed bowl because i wanted to remove all of the old fuel since it hadnt ran for over a year. i put about 2 gallons back in, above the 1 gallon reserve and would open to the full position to ensure any and all fuel had access to the fuel line.

Royse · Oct 9, 2012

No need to order anything just yet, your gas cap may be fine, specially since it didn't help when you left it off.
You could have rust and crud in your tank, and that could clog up a new sediment bowl.
Or, you could have gotten a bad new one.
I use a clean paint stir stick to dip the level of fuel in mine.
If you have 2 or three inches of fuel in there it should be up over the
"reserve" and you only need to open the valve about two full turns.
Out of that line, or the bottom of the carb you should get enough fuel to fill a pint jar in a minute or two.

Bill Rowles · Oct 9, 2012

It is hard to diagnose your problem from the info. provided, but I would drain the tank again and run a wire into the drain hole and flush the tank bottom into a clean can until no more sand,grit,dirt,etc. comes out. Then clean the new strainer/valve assembly with carb. cleaner and compressed air to be sure it is able to flow fuel. Reinstall the strainer/valve assembly then put 2 gallons of clean fuel in the tank and verify fuel flows before installing the fuel line. Blow fuel line with compressed air to verify it is clean and will flow fuel. Install fuel line and then start to check for fuel flow into carb. as outlined by others here. Don't dump dirty fuel used in flushing back in the tank.....and don't ask me how I learned this.

Michael lacey · Oct 10, 2012

Everyone, thank you for the help! I'll diagnose each aspect this weekend.

36 Coupe · Oct 10, 2012

Theres a passage from the bowl to the drain plug that plugs with rust so no gas when the plug is out dosent prove the bowl is empty.If you run out of gas on a gravity system you can have trouble getting gas to flow again.Friends and I had a cut down Model A Ford that would not start after it ran out of gas until you loosened the gas line at the carberator.My bandsaw mill has a water feed line of clear plastic tubing.You can see bubbles moving up the line when water is flowing.This tells me that air pressure is working againt fuel flow in gravity systems.The bowl has to be vented to allow gas flow.If the carberator bowl gasket were inverted it could block the vent.

Cliff(VA) · Oct 10, 2012

I once got a brand new out of the box CNH carb elbow screen that was completely blocked. I could not even blow air through it.

You might check. It sounds like the same symptoms.

Cliff(VA)

Michael lacey · Oct 10, 2012

Good to know, only $6. I'll try it...

NAA Gas Line and Carburater

Michael lacey

New User

Royse

Well-known Member

JCinKY

Member

Den N Ms

Well-known Member

JCinKY

Member

Michael lacey

New User

Den N Ms

Well-known Member

Royse

Well-known Member

Michael lacey

New User

Michael lacey

New User

Royse

Well-known Member

Bill Rowles

Member

Michael lacey

New User

36 Coupe

Well-known Member

Cliff(VA)

Member

Michael lacey

New User

Similar threads