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8 hp engine will not start...


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04-24-02, 08:11 PM   #1  
raymo8
8 hp engine will not start...

8hp Briggs&Stratton Go-Cart Engine

I cannot get my go-cart engine to start. I haven't driven it in over 2 years. Just recently, I have decided to fix it up and sell it but I can't get it running again. It ran fine when I put it away 2 years ago.
Currently, I put in a new spark plug, fresh gas, gave it an oil change, cleaned out the debris underneath the cylinder head, cleaned out the carburater, air filter, and made the reccomended needle valve adjustments. STILL NOTHING!!!! Someone please help me!!!

 
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04-24-02, 09:23 PM   #2  
First of all, check to be sure you have spark. Then we'll know where to go from there.


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04-25-02, 05:00 AM   #3  
raymo8
reply to cheese...

How do I test to see if there's a spark?

 
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04-25-02, 07:07 PM   #4  
Take the plug wire off, and insert a screwdriver blade in the connector at the end of the wire. Hold the metal shaft of the screwdriver about 1/4" away from a metal part of the engine, and have someone puul the cord while you watch for a spark between the screwdriver shaft and the engine. When you do this, hold the plastic handle of the screwdriver without touching the metal or you will get a good tingle. Don't worry, it'll scare you, not hurt you. The easiest way would be to buy a cheap spark tester at your local auto parts store.


"Who is John Galt?" - Ayn Rand (Atlas Shrugged)

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04-25-02, 07:50 PM   #5  
Hello: raymo8

Be sure the ignition isn't grounding out at the kill switch or anywhere else when you test for spark.

An alternate method to test for spark is to put the spark plug wire onto the spark plug and lay the plug on the engine head. When you crank the engine you should see a blue spark across the plug electrodes.

If you determine there is spark but the engine still fails to start, a quick shot of automotive engine quick start fluid into the spark plug hole, then reinstall the spark plug and attempt to start the engine.

If the engine runs briefly and dies, the engine is fuel starved. There is a fuel restriction somewhere in the fuel delivery to the carb or in the carb itself.

You may have cleaned the carb but the passages are still restricted and or plugged. Based upon what you posted about cleaning out the carb and how you did that task, I suggest you try the quick start trick and determine the results.

If the engine fails to run briefly after this test, there may be an ignition problem. Run these tests and post back the results. From that point the professionals within this forum can assist you further.

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Last edited by Sharp Advice; 04-25-02 at 08:09 PM.
 
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04-27-02, 01:38 PM   #6  
raymo8
No spark!!!

Tom and Cheese,

Thanks for your replies. I did your suggested tests to see if there was a spark and there was absolutely none in all of the tests. What should I do from here?

 
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04-27-02, 03:09 PM   #7  
Fisher
When you said you cleaned out all of the debris
was this under the metal top/side cover? The
debris, if so, may have been from mice, which
love to chew wires.
Post all of your engine's model numbers so we
can tell if your engine has points or not.
Fish

 
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04-27-02, 06:07 PM   #8  
raymo8
model numbers...

The model # is (190432). Hopefully that tells us something about the engine.
When I said that I cleaned, I meant that I took the cylinder head off and cleaned the burnt corrosion off of the top of the piston.
I also checked the wires and they appear to be okay. I couldn't agree more about how the mice like to chew wires. I have 2 lawnmowers that they seem to live in every winter.
Thanks for the reply. Please let me know where to go from here.

 
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04-27-02, 10:33 PM   #9  
There should be a black wire coming from the engine with a plug on it. Disconnect that wire and see if you have spark. If you are checking for spark with a spark plug, make sure it is good.


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04-28-02, 05:51 AM   #10  
raymo8
still no spark...

Hey Cheese,

I disconnected that black wire from the spark plug and held it about 1/4 inch away from the top of the plug while someone else pulled the rope. I was hoping to see the spark jump from the wire to the plug but there was nothing.

 
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04-28-02, 07:48 AM   #11  
Fisher
Just to clarify, the plug wire goes into a boxthat is bolted to
the engine up beside the flywheel. That is the coil, or ignition
module, etc. I take it that this is an older engine. If you see
a small wire coming from the coil going under the flywheel,
then that wire is going to a set of points and condenser, which
likely need changed. If the wire goes down to a terminal
below the carb, then it does not have points. If so,
disconnect that wire at the coil, then test for spark, but remove
the plug and lay it against the metal of the engine. If the
wire goes under the flywheel, then the points are the first
place to go to repair the engine. Briggs has an ignition
retrofit that eliminate the need for points, and you do not
have to pull the flywheel for just a few dollars more than the
point kit.
Fish

 
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04-28-02, 08:52 AM   #12  
raymo8
Finally got a spark!!!

Fisher,

You're right. My engine has the coil bolted above the flywheel. The coil has 2 wires attached to it. The main large black wire running to the spark plug, and a little 16 guage wire running from the back of it to the carburater on the outside in the back of the engine.
I disconnected the little wire from the back of the coil and ran the spark test with the spark plug resting on top of the engine head. I finally saw a spark!!!! although it wasn't a very powerful spark. But it did spark every time that I pulled the rope. What does this mean now?

 
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04-28-02, 09:03 AM   #13  
Fisher
It means that something was grounding out the wire.
Unplug the wire going to the connector below the carb
but plug the other wire back into the coil, then test again.
It should still spark, if not the wire must be bare and
touching the engine somewhere. If so, put the engine back
together, then start the engine. To stop, you will have to
ground that terminal out to stop it or choke it out. Then from
there you have to find out what is grounding the wire from
your cart to the engine.
Fish

 
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04-28-02, 10:46 AM   #14  
raymo8
Got spark again but still not starting...

Fisher,

I just ran the test that you recommended. I reconnected the small black wire to the back of the coil and then disconnected it from the bottom of the carburator. Again, I got a spark. So I put the spark plug back in and tried starting it with the small black wire disconnected from the carburator. Nothing! So, then I connected the black wire back onto the coil and carb. Still nothing! I checked the wire and it's not grounding anywhere or damaged. It is giving me a spark but the engine won't fire up. I'm starting to think that it must be the carb now. It may be getting too much gas because it will occasionally drip from the bottom of the carb after pulling it several times. Or could it be something else? I'm sure that I'm getting a spark but it won't start up. What should I do next?

 
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04-28-02, 11:47 AM   #15  
Fisher
Those carbs flood easily on this model, so you have
plenty of fuel it sounds like. Did you remove the nut
holding the flywheel? If not tighten back enough
it can shear and won't start.
But looking again through the past posts, you may
have a compression problem as well. Put the plug
in and try to rotate the flywheel backward by hand.
It should reach a point that it is real hard to
keep rotating, even want to "bounce" back. If your
valves are leaky, it will just slow and give a little
resistance at that point.
All this being said, I am assuming you are using
clean fresh fuel.
Fish

 
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04-28-02, 12:56 PM   #16  
raymo8
Fisher,

I have put fresh gas in and that doesn't do the trick either. I just ran the compression test too. It fights at a certain point when I spin the wheel backwards and gives a little cough or puff of air release. You can also feel the wheel fight you when you pull the rope too. There is plenty of strength in the compression.

This whole issue boggles my mind because the engine is only 5-6 years old with no more than 200 hours on it. It also worked fine when I put it away 2 years ago. It has however always had a problem where I would need to push on the gas pedal while someone else pulled on the rope. Otherwise, it would not start. That was the case ever since it was brand new. Does this give you any ideas of what's wrong?

 
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04-28-02, 02:54 PM   #17  
Fisher
Pour a dribble of gas in the spark plug hole, then try
it. If it starts then dies, then it is a fuel problem.
Compression may still be suspect because you did
not say the flywheel wanted to "bounce" back,
and heard a little puff of air.
When you told of cleaning the gunk off of the
piston and valves led me to suspect the valves
as leaking. But try the dribble of gas in the plug hole
and let us know.
Fish

 
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04-28-02, 06:23 PM   #18  
raymo8
gas in the spark plug hole...

Fisher,

Hey. I tried the gas in the spark plug hole. That has always worked for me in the past when I would try that with starting lawnmowers. But this time, it wouldn't do the trick.

As far as the compression goes. How far is it supposed to bounce back? When I turn it backwards it will catch once in every revolution usually. Then when I let it go while holding it at the catch, it will bounce back no more than an inch. It WILL bounce back slightly though.

Also, if this is a compression problem, is it hard to fix or not to mention, expensive to fix?

Thanks for your help so far.

 
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04-30-02, 10:34 PM   #19  
Interesting...
I would try this;
Go to your parts store and buy a can of starting fluid. (This stuff is really not good for your engine) Remove the air cleaner from your engine and have a friend spray a short burst (no more than 2-3 seconds) into the carb throat while you pull on the rope. Make sure the throttle is open and the switch is set to run.
If you have enough spark and compression your engine should start. It probably will die quickly. If it starts and dies, you have a fuel delivery problem. Most likely your diaphram (on the side of, or underneath the carb if it has one) is bad.
If it doesn't start you've most likely got a spark problem. If the engine is only 5-6 years old, you have a magneto ignition. Pull off the flywheel and check to see if the flywheel key is sheared. It sounds like you have pretty good compression. Did you put a new head gasket on it? Are the head bolts tight?
I wonder about the "cough" you're hearing. A sheared or even a partially sheared key will throw your ignition timing off. Be sure and tighten the flywheel really good when you go back with it.
Let us know what happens!

 
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