Continuous issues with fuel leaks on Tecumseh carbs!

waylonJ

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I have worked on 3 different Tecumseh carbs bolted typically to an Eagle 1 (or is it Eager 1) engine - these are the basic 5hp-ish carbs with a brushed aluminum float bowl.
Well color me frustrated at these carbs leaking! I have replaced the needle seat, needle, bowl gasket and bowl-nut gasket and they just continue to leak. Now that I have vented I think the culprit is simply a crappy aftermarket rebuild kit from AmaXion. The old float bowl gaskets, although fully worn and broken, were just like a super big o-ring with a circular profile. The rebuild kit included a float bowl gasket like a ribbon or bracelet with a rectangular profile. I did notice that the float bowl would leak if tilted - fuel would leak from the gasket / seam area.

Also, unrelated suggestion:
With all the leaky carbs I got quickly tired of finessing the carb back onto the mower and buttoned it up with 12 different bolts just to find it was leaking again I had the good thought of finding an old gas jug from a mower. I mounted this gas "supply" to my workbench up about 1 foot off the surface to make it elevated. I ran a fuel shutoff and tubing. I could then, with the carb in my hand, turn on the gas and inspect for leaks. It saves me a bunch of aggravation for sure. I will even pull the float bowl and then press the floats up, turn on the fuel and make sure the float shuts off the supply when raised. I can even tell where in the range the bowl is adjusted to make sure it's not too high or low.

Anyhow, would you all concur that the gaskets on the aftermarket kits are garbage? I have some genuine rebuild kits on the way and I am anxious to see if they work.
 

Rivets

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Get yourself a Tecumseh carb kit 631021B and install it after cleaning. Make sure that the rings on the new seat a installed toward the carb body. Square cut bowl gasket is the correct style, not round O-ring. This is the procedure I use and recommend.
Needle and seat replacement.

Remove the carb, and then remove the float bowl. Check the float bowl jet (which is the bowl screw) and make sure the jets both horizontal and vertical are clean and open. Tip the carb upside down and remove the float pin and float with needle attached. Look in the float needle passage and you should see the red float seat at the bottom of the passage. This is where a #5 crotchet hook would come in handy as you need to remove this seat. If you have no hook, but compressed air, you can blow through the fuel inlet and try to pop the seat out. Put your thumb over the passage to prevent the seat from flying who knows where. No air or hook try bending a stiff paper clip to dig the seat out.

I would either give the carb a good 24 hour soaking or have it ultrasonically cleaned at this time.

With the seat out clean the passage way with carb cleaner. Now you must find a drill bit slightly smaller than the passage way, to be used to press in the new seat. Apply a very, very small amount of a very light lube to the new seat. 3-1 oil or lighter, to help seat it better. Carefully insert the new seat in the passage way with the rings on the seat down toward the carb body. Slowly and carefully force the seat down with the back end of the drill bit. Once it is seated, check to see that it did not flip and the rings are up. Next check to make sure that the float does not have any liquid in it. If it does, replace. If everything looks correct, attach the new needle to the float and install with the float pin centered. It everything is correct, the float should seat level to the carb body, when looking at it upside down. If everything looks good reattach the float bowl, making sure that both the bowl gasket and the nut gasket seal properly. Reinstall on the engine and test unit. Remember to have patience and take your time. Good luck, but I don't think you'll need it.

PS: On the side of some Tecumseh carbs you will find a plastic cover. Under this cover will be an idle jet. Remove it and check to see that the jet is open both horizontally and vertically. You should be able to push the old float needle wire through the vertical opening.
 

StarTech

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Personally I would be getting a copy of the Tecumseh Carburetor Identification, Troubleshooting and Service Manual as the OP also needs to test the pop off pressure and set the float height.

Form No. 695907 R12/07 <Deleted Link>
 

waylonJ

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Thanks Rivets! I always appreciate your responses! Very helpful for sure.

StarTech - thanks for the advice. I will have to find one of those guides!
 

kwgerloff

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Believe it or not the clip on the float ,the long end has to be facing the air filter side of the carburetor. I also learned this the hard way. I do not know why it makes a difference on the way it is facing but it does . It also states the same thing in a Tecumseh manual that i have.
 

Born2Mow

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The actual gasoline level should never come up to the FB gasket. The gasket is there to stop "splash" only, NOT to be submerged in fuel.
 

Nocrank Bill

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I have worked on 3 different Tecumseh carbs bolted typically to an Eagle 1 (or is it Eager 1) engine - these are the basic 5hp-ish carbs with a brushed aluminum float bowl.
Well color me frustrated at these carbs leaking! I have replaced the needle seat, needle, bowl gasket and bowl-nut gasket and they just continue to leak. Now that I have vented I think the culprit is simply a crappy aftermarket rebuild kit from AmaXion. The old float bowl gaskets, although fully worn and broken, were just like a super big o-ring with a circular profile. The rebuild kit included a float bowl gasket like a ribbon or bracelet with a rectangular profile. I did notice that the float bowl would leak if tilted - fuel would leak from the gasket / seam area.

Also, unrelated suggestion:
With all the leaky carbs I got quickly tired of finessing the carb back onto the mower and buttoned it up with 12 different bolts just to find it was leaking again I had the good thought of finding an old gas jug from a mower. I mounted this gas "supply" to my workbench up about 1 foot off the surface to make it elevated. I ran a fuel shutoff and tubing. I could then, with the carb in my hand, turn on the gas and inspect for leaks. It saves me a bunch of aggravation for sure. I will even pull the float bowl and then press the floats up, turn on the fuel and make sure the float shuts off the supply when raised. I can even tell where in the range the bowl is adjusted to make sure it's not too high or low.

Anyhow, would you all concur that the gaskets on the aftermarket kits are garbage? I have some genuine rebuild kits on the way and I am anxious to see if they work.
Agreed about kits from “ The Zon”. I don’t think its their fault that those rebuild kits are sub standard, but I only use them in a rush. The last one I used, swelled the bowl gasket so bad I could not reuse it after being on the bowl for 1/2 hour. Will stick to OEM from now on.
 
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