Small Engines (Lawn Mowers, etc.): 5 HP B&S MODEL 130992, engine shaft, air leaks

Question
-------------------------
Followup To
Question -
it only runs on full choke
it has a pulsajet carb
I've cleaned it twice and set the
needeljet at 1 1/2 turns
the valves look ok
what do you think could be the
problem

Thanks F.H.
Answer -
How old is the engine?  Is the tank metal and the carburetor aluminum?

Let me know.
Eric

The answer is yes on the tank
and carb
the mower is marked
LAZY BOY MODEL OSPH-79
or OSRH-79? the paint is coming
off
the engine is marked
MODEL     TYPE     CODE
130992    0577 01   78122006
the mower has big tires
on the back and an extended
mowboard in front
that runs off of a belt
with a cyntrifical clutch on the
engine shaft  

Answer
According to the code number, the engine is a 1978 model.  It could be a points/condenser problem, but most likely it's carb related.

Make sure the intake tube is tight and not leaking.  I've had the intake tube gaskets leak right where it bolts to the intake on the engine block.

The onther problem those engines have is warped carburetors.  A warped carb creates air leaks unseen to the eye but wreaks havoc on the intake system.  You can remove the carb pick-up tubes and use a good sander or flat file to "true" the carb again.  I use a file at home and it works well...just takes a little more time.  After the carb is flat again, re-install and see what happens.

What is the part number for you carburetor diaphragm?
Let me know.
Eric