OH195 carb leaking and no fixes help

[DrewBob]

My engine was surging so I rebuilt the carb. It ran great but began leaking gas from the drain plug on the float bowl. The carb is a series 1 emission. I replaced the bowl with a
new one without the drain and the carb was leaking just enough gas to make my garage smell like gas.
I replaced the o-ring between the float bowl and carb body and it started leaking much
worse. The gas is leaking out of the o-ring and backing up the primer hose. This is what I have tried.

1. repaired the original float bowl by removing the drain and plugging the hole with a screw head and JB Weld. Reinstalled original bowl.

2. Replaced the needle, seat, gaskets making sure the grove was down on the seat and set the float to 11/64.

3. Made sure the needle clip was pointing the correct way and tested float in a sink of water. Set the float level to 7/32

The carburetor still starts leaking pretty heavily after about 15 minutes. I have searched and don’t know what else to try. I would appreciate any help

 

[reynoldston]

The Tecumseh carburetor has a replaceable needle valve seat which you can install upside down Is that installed right ?

 

[Rivets]

As reynoldston said, sounds like the float needle and seat are not working properly. Also, as you know, if the gasket between the float bowl and carb body is not installed correctly, the carb will leak, even if the float is set properly. If it was me, I would pull the carb and double check the needle and seat. Here is a procedure I use.

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.

 

[aj-allen]

Is this engine on a snowthrower? Does the the primer have a whole formed in the center of the bulb (the newer one do)? Looks like this:

If it does not it is likely that the carb bowl vent is plugged should be here:

 

[Rivets]

In my opinion a plugged carb vent will not cause this problem.

 

[ILENGINE]

I plugged carb bowl vent will cause siphoning, but I suspect that either the new rubber seat is damaged, not installed correctly, or has come in contact with carb cleaner and has swelled.

 

[DrewBob]

The seat is installed the right way and the float is not leaking and appeared to install correctly. The weird thing is; with the carb installed and the bowl off, just a little pressure on the float shuts off the gas.
I was told by the shop that a poor seal on the bowl gasket wouldn't cause a leak if the float were set correctly, is that true? It has gotten worse so it is something with float, needle, seat or gasket. I will buy all new parts and try again. This is a personal challenge now.

Thanks for your help and please post if you think of something else for me to try.

 

[Rivets]

If your dealer is correct you wouldn't need a gasket between the bowl and carb, in my opinion he hasn't worked on many carbs. Yes, I would start over with kit number 631021B and follow the procedure I posted.

 

[DrewBob]

Success !!!!
My machine is now bone dry and running great.
Thank you all for your help! !

I am not sure what the problem was: I replaced the float needle and seat, and gaskets being very careful. I also ran a copper wire into the vent hole.

 

[Rivets]

Thank you for being a member who posts back. Most of the time we never know if problems are ever solved. Make sure to drain the unit dry, carb also, at the end of the season to eliviate future problems.