Tecumseh carb issue

U

Unk

Forum Newbie
I was given a Lawn Boy mower that didn't have a carb on it. I ordered a Hipa carb. It runs good except at idle it runs lean. I can richen the mixture with the main jet adjustment but at full throttle it runs real rich. I readjust the main jet and it runs good. I've looked for a pilot circuit or idle mixture adjustment screw but don't see either. Am I missing something?
 
send us a link to the carb you bought, or post photos. Lots of times on these replacements you need to figure out where the existing carb idle jet is, then figure out the size, compare it and then redrill the one in the new carb, or if it unscrews, swap it. Very few carbs made today have adjustable high and low speed jets due to epa regs. Make sure you check the carb, gaskets and intake manifold for vacuum leaks. They may not show up at high speed but they will at idle. So will valves needing adjustment.
 
It would be sure nice to know which of the fifty different models Tecumseh produced and which of the fifty different models of Lawn Boy mowers you may have. We need model and serial numbers for the mower and model and spec numbers for the engine. Plus part number for the carb you purchased.
 
I have no clue about your carb or engine. Would guess at if the carb has no pilot circuit then it was not made to idle like a car engine. Probably a set RPM at 3400rpm guessing.

Check the highly overlooked float height level.
 
A Lawn Boy with a Tecumseh?

Welcome Newbie:

Before we jump into blind guessing and wasting your time and money, we need to know the information off of the chassis label and the engine.

We have lots of experienced people, but most of us retired our crystal ball years ago. We need machine data to actually help you in a meaningful way without this turning into a confusing gaggle.
 
Last edited:
Yes, Lawn Boy went to Tecumseh when they switched from 2-cycle to 4-cycle. I’m assuming (which I shouldn’t do) after reading his first post that he has a 4-cycle engine. Wouldn’t be the first time I was wrong and looked like an idiot.
 
Hello Rivets,

Back in the late 70s when I started out, I thought all Lawn Boy push and walk behind mowers 2-stroke, but I also forgot that they had a 4.5hp Tecumseh version. They even had a few with Briggs and Stratton up until they quit making them. I had to do a little research and search through some old manuals.
 
You must log in or register to reply here.
Back
Top