Export thread

L108 John Deere Lawn tractor

#1

E

elvasam

Not starting. Sounds like it is going to but doesn't. Tried removing gasoline and putting in new. Checked for fuel blockage - nothing. New spark plug and correctly gapped. Help?????:confused2:


#2

L

Lawnranger

Based on the extremely limited information you have provided I will give the following for you to perform:

An engine needs three factors present and in the correct proportion to start and run properly - the correct air/fuel ratio (fresh, quality fuel is a must), sufficient compression (arguably 90 P.S.I. or better) and sufficient spark at the correct time. If one of these factors is missing or out of proportion, the engine will run poorly or not start/run at all. Your task is to find the missing factor by inspecting and testing the systems involved. Which factor is missing or out of proportion in your case?

If you do not know how to check for spark or perform the necessary checks and tests, youtube has some videos that will guide you through the process. Simply search youtube for what you want to test or check.

There are conditions that will prevent an engine from starting even though all three factors are correct such as a plugged muffler/exhaust, old/contaminated fuel and I am sure there are more possibilities but I will not try to list them all here so I am going on the assumption that one of the factors is missing and that all other components are functioning properly.

You will need a compression gauge to test compression so if you do not have one or do not have access to one you will need to take it to someone who can test it for you. You will also need a spark checker which can be made from an old, working spark plug by clipping off the side electrode, connecting the plug to the lead and resting the metal hex of the spark plug on the metal part of the engine but this is not always as easy as it seems as many engines have plastic shrouds and other obstacles in the way. My method of testing for lack of fuel is to spray a shot of carburetor cleaner directly into the carburetor (air filter removed) and try to start the engine. If the engine starts and runs for a second or two and then dies you most likely have a fuel delivery problem.

Perform the necessary tests, report back with your findings and you will receive further advice based on your answers.


#3

E

elvasam

Ty I will try this and get back with you. I am a female with limited knowledge when it comes to mowers. Dad passed away and I am the only child willing to handle everything for mom. I'm learning though. :):rolleyes:


#4

E

elvasam

I tried the carbarator spray trick of yours and it still won't kick in. Engine motor just keeps trying though


#5

Carscw

Carscw

I have never got a engine to start with carb cleaner but I do know if it is running and you spray carb cleaner in the carb the engine will shut down.
What I do is put a coke bottle top of gas in the carb.

Sent from my iPhone using LMF


#6

L

Lawnranger

I tried the carbarator spray trick of yours and it still won't kick in. Engine motor just keeps trying though

Only two factors to go. I do hope it is something simple and inexpensive that you can repair yourself.


#7

L

Lawnranger

I have never got a engine to start with carb cleaner but I do know if it is running and you spray carb cleaner in the carb the engine will shut down.
What I do is put a coke bottle top of gas in the carb.

Sent from my iPhone using LMF

If you have a small engine that has a fuel shut off valve you can test this test by closing the fuel shut off and running the engine until it runs out of fuel. Then shoot a short blast of carburetor directly into the carburetor and immediately crank the engine. It will start and run for a second or two as it uses the CC as fuel.

The reason an engine will die if you shoot CC into the intake while it is running is because you have made the air/fuel mixture way too rich and in my post above I mentioned that an engine needs the correct air/fuel ration which is approximately 14.7:1, AKA stoichiometric mixture. If you upset this ratio too far either way the engine will die. Too rich = not enough oxygen, too lean = not enough fuel.


Top