Tecumseh OHV125

[bwestbrook]

I am fixing a older Murray with a Tecumseh OHV 125. Initially it was no start not getting fire. I replaced coil which was a quick fix but once I got it to start it would spit sputter and backfire. I checked valves and they were good. I cleaned carb and put a needle and seat and bowl gasket. It was also leaking fuel out of carb. Needle is seated correctly but still leaks. Now it will puff white smoke out of exhaust and try to start but of course is flooding out. I have rebuilt many carbs but this one is getting me. Haha. Where did I go wrong?

 

[ILENGINE]

Either the new needle valve and seat have a piece of something stuck to it or is faulty. Check to make sure that the bowl vent isn't plugged because that can cause flooding also.

 

[Rivets]

White smoke tells me you have water in you fuel. Take a Q-tip to the fuel inlet seat to make sure that there is not any dirt or small nick in the seat.

 

[bwestbrook]

I will check seat again. I checked fuel for water in a clear jar plus it is fresh. I didnt see any but I will drain and add new. When it lets that puff of smoke out is when it tries to start and spits fuel out of the carb. Will not start at all now. Could I have a valve problem of some sort?

 

[Rivets]

What color is the smoke? White would indicate water, black would be excess fuel and blue would be oil. If it just occurs during start up, I would not be to concerned as this could be just excess condensation that would burn away quickly.

 

[bwestbrook]

The way it puffs out could be just condensation. Where is the bowl vent on this carb?

 

[Rivets]

If you look straight into the carb air horn, you should see a hole about 1/8" in Diameter at either the 2 or 10 o'clock position. That is the vent hole for the float bowl.

 

[bwestbrook]

I found it and it is clear. The other end of that is under the welch plug correct?
Now if you look straight into the venturi, of course there is a passage coming straight up through the middle. But if you look just in front of that one there is another small passage in the bottom at an angle. What is that? Because that is where it is leaking from. I have been sitting here watching it to verify exactly where it is coming from.

 

[Rivets]

That is a secondary vent. If gas is coming out there your needle is not seating properly and the engine is flooding.

 

[bwestbrook]

I closed the jet on the bottom of the bowl and now it is coming out of the bowl vent.