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Discussion Starter · #1 ·
I got my LMH carb apart and have a few questions..

1 I took the float shaft out of the float ass. Got the seat out of carb,, and instructions say to put back togather in reverse order.. OK that is simple enough.. But it says to put back float valve, needle and gasket. There was no gasket... Just needle and seat I do have a gasket left in the kit,, But not sure if it goes before the seat... OR where-ever..

2 The Float Drop Setting,, says to reverse casting to normal position allowing the float to not drop more than 3/16 of an inch,,,Mine moves about an inch ( drops down from top to bottom )... 3 / 16 to an inch would mean alot of bend in the tab.. not ready for all that bending in the bowl to play with..

3 The bowl spring ,,, the one that goe's under the tab and thru the bowl and casting,, Is that suppossed to be under spring pressure...I'm not sure where the one end was..One end gos under the adjusting tab, along with the seat spring,, and the other with a short 90 degree bend ,,,with no load, it sits where the bowl gasket is... Should that be turned 180 degrees ,faceing the center of the bowl.( With some load on the spring ) I tried it,, the float shaft is a bear to line up !! in the spring center

I tried to find a vid of someone doing it and saw nothing about the spring and it's position..
 

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Can you help us help you? What make and model carb. Zenith? Walbro? What's it off of? Wisc. Tech. or B&S?
 
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First off, if you send me your Walbro LMH number, I can send you a picture of what the order of operations should look like. I have not rebuilt an LMH before.

The needle looks to sit on a rubber "stopper" of sorts that is pressed up into the body casting. Do you have that?

I think if you solve the needle situation you will probably help the float setting.

That "float support spring" is probably used to help seal the needle by putting some pressure against it via the float. Do you have a fuel pump in your system?

Ben W.
 

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Can you help us help you? What make and model carb. Zenith? Walbro? What's it off of? Wisc. Tech. or B&S?
LMH is a Walbro Carburetor

I got my LMH carb apart and have a few questions..

1 I took the float shaft out of the float ass. Got the seat out of carb,, and instructions say to put back togather in reverse order.. OK that is simple enough.. But it says to put back float valve, needle and gasket. There was no gasket... Just needle and seat I do have a gasket left in the kit,, But not sure if it goes before the seat... OR where-ever..

I'm thinking they just mean the Bowl Gasket........

2 The Float Drop Setting,, says to reverse casting to normal position allowing the float to not drop more than 3/16 of an inch,,,Mine moves about an inch ( drops down from top to bottom )... 3 / 16 to an inch would mean alot of bend in the tab.. not ready for all that bending in the bowl to play with..

Usually new floats you get are pre-bent and generally at the correct setting

3 The bowl spring ,,, the one that goe's under the tab and thru the bowl and casting,, Is that suppossed to be under spring pressure...I'm not sure where the one end was..One end gos under the adjusting tab, along with the seat spring,, and the other with a short 90 degree bend ,,,with no load, it sits where the bowl gasket is... Should that be turned 180 degrees ,faceing the center of the bowl.( With some load on the spring ) I tried it,, the float shaft is a bear to line up !! in the spring center

I tried to find a vid of someone doing it and saw nothing about the spring and it's position..

I cant help you with that one as I'm not familiar with the style of spring used in the Walbro Carbs.
 

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Just looked at a lmh carb and there is nothing on mine to bend for float drop,it drops until it hits the bowl.Also looked in manual and it has nothing about float drop just float height..

Can't help with the spring,I just know it's a pita to get it in there and I put mine in about 4 differant ways and it did not seem to do anything,must be a secret cuz the manual isn't saying either.
 

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Discussion Starter · #7 ·
I think the spring you are asking about is 22 on this diagram

attachicon.gif
walbro.PDF
Thats the one. .One side sits under the float tab,,,,, The other with no tension on it,, lies in the bowl gasket area. That's why I'm thinking it must be rotated ( a load put on ) to the center for clearance .
 

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Can you help us help you? What make and model carb. Zenith? Walbro? What's it off of? Wisc. Tech. or B&S?
Walbro LMH -1 Tecumseh HH150 engine From a 1556 Bolens

First off, if you send me your Walbro LMH number, I can send you a picture of what the order of operations should look like. I have not rebuilt an LMH before.

The needle looks to sit on a rubber "stopper" of sorts that is pressed up into the body casting. Do you have that?

I think if you solve the needle situation you will probably help the float setting.

That "float support spring" is probably used to help seal the needle by putting some pressure against it via the float. Do you have a fuel pump in your system?

Ben W.
LMH-1 Most don't list a 1 series but it is simaler as a LMH - 10 ---K1

Yes I have the seat That looks similar to a gasket

Yes I have a pump of sorts,,,,-- An auto-pulse pump.
 

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I may be able to help if it's at all similar to the carb on an HH120, the spring helps keep the float tensioned "up" i.e. to keep more pressure on the needle to close it. I was told it was to stabilize it during bouncing and vibration. The one tab goes under the float bowl o-ring and the other tab hooks to the float. It's a bear to install but a small pick or jeweler's screwdriver helps a lot.

As for float height the carburetor needs to be inverted to check that, i.e. upside down. You want to check the clearance between the float and the body of the carb when the needle is closed. That's what determines when the needle shuts off the fuel flow coming into the carb.

Hopefully this helped, I had a lot of trouble digging up info when I did mine and I should've thought to take some photos for others to see. I'll try to dig up some pictures or illustrations for you...
 

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Discussion Starter · #10 ·
After studying the PDF that New restorer sent... ( Thanks ) It looks closer to the needle and seat on the tecumseh carb than the walbro carb .. But it doe's have the spring,, 22 That I am trying to figure out it's position.. for the 90 degree bend ..

This is very difficult to discribe unless you've been there --done --that type of scenario
 

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Discussion Starter · #11 ·
Just looked at a lmh carb and there is nothing on mine to bend for float drop,it drops until it hits the bowl.Also looked in manual and it has nothing about float drop just float height..

Can't help with the spring,I just know it's a pita to get it in there and I put mine in about 4 differant ways and it did not seem to do anything,must be a secret cuz the manual isn't saying either.
Bill : If you look at the PDF on this subject , on page 250 you see the parts diagram and a brief bit of directions for float adjustments.. Continue down and there is,,, on page 251,, on the upper left a bit more on the carb and a pic. T-6 that shows the bowl adjust . OR as it is called ( travel ).

I put it together yesterday and a'm waiting for it to warm up a bit to try.. Maybe today...Will keep posted !!
 

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Discussion Starter · #12 ·
O K I put the carb on,,, hooked up the fuel and impulse pump lines,, Tried to start it and it seems that it is starveing for fuel..

Here's what I did turned the bowl settings to 1 1/2 out,,,,,,,,, Turned the air fuel mix out 1 1/2

NO start

Dry plug---- Sprayed gas in carb,,,,started for about 3 sec.

Choked it and added some throttle....--Nothing

Turned the bowl jet out to 2 turns --- Nothing..

Kept spraying gas in to carb to keep it running... That worked but a pain in the BUTT.

NO SPRAY--- DIED.

I seem to be starveing for fuel..... I push the bowl bleed on bottom of bowl,,,,lots of gas bleeding out..

I shook the carb just before I installed it to hear the float was loose and the float should work properly,,

I still have a dry plug...... I have gas,,,,, I'm getting spark-------- It runs,,, when primed with gas and a spray bottle..

Why won't the gas enter the carb ??? It appears like the bowl jet is not letting the gas up to the carb. throat.. ( It was cleaned and floed gas when I soaked it in carb cleaner and blew it clean ) Before takeing it back off the engine ,, Any ideas That I should try. ???

I hope I discribed this OK,,, But any input would be greatly app. Thanks sodi
 

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Your description certainly indicates it is starving for fuel. When I rebuild a carb, after I have gotten the float and bowl on I will blow through the fuel inlet with the carb in normal position. You should be able to blow air into it. Then I turn it up side down and blow again. You should not be able to blow air through.

When you had the Carburetor apart did you make sure the jet's were clear? How about the passages? Did you put the main jet back together as per the PDF?
 
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Summer.
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In the PDF it shows a vent hold for the float bowl, it is also discribed as a atmospheric pressure stabilizer vent, make sure it is cleare.

I do not know with your carb but on many the bowl vent is on the mouth of the carb were the air cleaner assy bolts on to.

On others it is right above or next to the fuel inlet of the carb.
 

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Discussion Starter · #15 ·
Your description certainly indicates it is starving for fuel. When I rebuild a carb, after I have gotten the float and bowl on I will blow through the fuel inlet with the carb in normal position. You should be able to blow air into it. Then I turn it up side down and blow again. You should not be able to blow air through.

When you had the Carburetor apart did you make sure the jet's were clear? How about the passages? Did you put the main jet back together as per the PDF?
YES the jets were clear and all passages had cleaner and air going thru them .. Did I put the main jet back together as per the PDF.. ??? the only thing that was unfamiler to me was,,, on the needle and seat, for the float...The seat per instructions said put the seat with the ring in the seat faceing the carb. body... The seat on my rebuild kit had 4 small diamonds stamped into them. NOW I looked at it with a magnifying glass and the seat seemed to have a taper to it,,So I followed the taper to the needle...That meant that the 4 diamonds went to the body side of the carb. ( diamonds down when up side down ) --- SEE PDF ---

I'm not sure how many turns I can go out with the bowl jet before it wants to unscrew out..

I might try to take the bowl off and blow thru the fuel line..and raise the float and lower and check for air.. GOOD tip there Bill !!

AND yes the Bowl vent is clear,,, It is a rectangle in front of the filter plate.. Thanks for asking Trowel ... :D

More to come !!!!
 

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You should be able to turn the screw out quite a few turns, but it seems to me that most of the carburetors I have worked on were in the ball park from 1 to 3 turns. If you aren't getting anything at 2 turns that sounds like something is amiss in the main fuel circuit of the carburetor. I know this sounds crazy but make sure you didn't put the float in up side down. I actually had a tractor come in like that.
 
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