Briggs& Stratton engine will not turn over

JimP2014

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I actually was thinking this just about the fan that even if I get all the fins I'm still going to end up with around 700° f. But like you're saying regarding the governor, since the component is inside and I'm not an engine expert wouldn't I would not know this if this is broken or not. If something is broken on the outside of the engine I could clearly see that. But I will look at this tomorrow and see if all the symptoms that the sentient exhibited add up to a governor issue. Although I can say I did try and adjust it maybe 10 days ago and it seemed like I said it correctly or I should say it was set correctly and I didn't do anything more than loosen up a nut and then tighten it back up
But the weird thing is maybe 5 days ago it was running very smooth. Everything seems smooth and the engine temperature was about 450° Fahrenheit. Maybe 500° and then something happened then and then it went back up to 800° f
 

JimP2014

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Did you ever get the engine model and date code? It should be stamped into the valve cover. If hard to read, get some "grime" on your finger and rub it across it. The grime will fill in the letters and give you contrast. Also can take a photo of it, if hard to read.

There are several parts (fan included) that require the date code to get the correct fan.

Since your exhaust is getting superhot, it seems you are running lean... Popping and sputtering could be an ignition issue on top of this. One thing I have seen is the ignition switch (or connections) going bad and intermittently killing the coil.

Spark related, I would pull the plug and short the metal base of the plug to the engine, then crank it. If you get spark your ignition system works to provide spark. Since it starts, this is probably ok. To rule out other issues "killing" spark intermittently, pull the kill wire from the coil (you will have to remove the air cover). Start it and see if it runs ok. If so, then something is killing the coil (ign switch, safety switches etc.). NOTE: I have seen spark look "ok" with a spark checker and have this issue. You could kind of see the spark "stutter" but it was still sparking. You can kill the engine by pulling the plug wire (using insulated pliers) or short the coil kill terminal to the frame of the coil with a screwdriver. If the engine continues to run rough with the kill wire removed, then the only spark related issue can be timing related.

Timing related spark issues would be (1) sheared flywheel key; (2) Coil upside down; (3) coil gap to magnet on flywheel; (4) wrong or bad parts (coil, flywheel, plug, plug wire); (5) if your insulation on the plug wire is weak, cracked or chewed by mice, the spark signal can be messed up as it will jump the air gap to the engine block (this will cause missing);

I suggest, going through systematically to verify each (spark, fuel, air, compression, valve lash; etc.) one system at a time.

As for running lean; Check air flow; make sure you don't have any air drawing in the system between carburetor and engine; (i.e. check the gasket between the carburetor and the engine; make sure the bolts are tight). You can also spray carb cleaner; or similar at the gasket point while the engine is running (make sure it doesn't enter the front of the carburetor though)... If it starts to run smoothly when you squirt it with carb cleaner (and it is not going into the front of the carb), then you have an air leak between the carb and engine. Also check the throttle and choke shafts where they enter the carburetor. If these are worn, you can get air leaking in there. Also check to make sure your throttle/choke plates are securely attached to the shafts (by looking into the input side of the carburetor)

Another test for running lean, is to move the choke to slowly towards the closed position and see if it starts to run smoothly.

Others may be able to chime in similar tests, but I would suggest going through systematically and prove out each system.
PXL_20240624_104847121~2.jpg


It's late at night, but it seems like you have a pretty exhaustive list of things to look at. And I absolutely will read it tomorrow morning. But I've included the engine code and it's just so hard to read and I'm pretty sure this is the best photo which is cropped that I have

Jim made
 

JimP2014

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View attachment 69143


It's late at night, but it seems like you have a pretty exhaustive list of things to look at. And I absolutely will read it tomorrow morning. But I've included the engine code and it's just so hard to read and I'm pretty sure this is the best photo which is cropped that I have

Jim made
I started to take a look at what you wrote and I absolutely will remove the kill wire because right now it starts right up it hunts and surges and the temperature gets up to about 800° f ine. I didn't know at the time what the purpose of removing the kill wire was, but now I know and I can actually shut it down manually or an easier way is just to move the throttle to the lowest position and it will stall out I'm sure.
 

dwzkd

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View attachment 69143


It's late at night, but it seems like you have a pretty exhaustive list of things to look at. And I absolutely will read it tomorrow morning. But I've included the engine code and it's just so hard to read and I'm pretty sure this is the best photo which is cropped that I have

Jim made
This is a good enough photo....


31P677-0804-B1 090130??


The last two digits are harder to make out but it looks like 7D or ZD... These will not likely matter much.
 

DABS

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I actually was thinking this just about the fan that even if I get all the fins I'm still going to end up with around 700° f. But like you're saying regarding the governor, since the component is inside and I'm not an engine expert wouldn't I would not know this if this is broken or not. If something is broken on the outside of the engine I could clearly see that. But I will look at this tomorrow and see if all the symptoms that the sentient exhibited add up to a governor issue. Although I can say I did try and adjust it maybe 10 days ago and it seemed like I said it correctly or I should say it was set correctly and I didn't do anything more than loosen up a nut and then tighten it back up
Just food for thought. I happen to have one in here with the same issues and once I took the pan off pieces of the governor were everywhere. Aluminum pushrod on the intake was also bent as the heat allowed the valve guides to move. Yours may be different but a magnetic dial indicator could tell the story.
 

JimP2014

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This is a good enough photo....


31P677-0804-B1 090130??


The last two digits are harder to make out but it looks like 7D or ZD... These will not likely matter much.


I have been using the above website link for the engine and this goes back like 3 years or more.

I also considered trying to use steel wool on the parts I couldn't read and then I was thinking maybe I just erase everything so I did not attempt that.

Jim
 

JimP2014

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Just food for thought. I happen to have one in here with the same issues and once I took the pan off pieces of the governor were everywhere. Aluminum pushrod on the intake was also bent as the heat allowed the valve guides to move. Yours may be different but a magnetic dial indicator could tell the story.
I have never heard of a magnetic dial indicator. I will look that up later and its usage. But one thing I was messing around with few weeks ago is trying to figure out if some of the safety features were screwing up the engine and then since I had constant spark I thought no issue with the safety features, but just tonight the idea of disconnecting the kill switch off the ignition coil seems pretty simple to do and could have a major impact on this hunting and surging. So so I absolutely will do that first and foremost tomorrow and see if it makes any change with this hunting and surging issue. I don't think you originally said that, but either way I'm putting it out right here and I hope it's just that simple.

Jim
 

DABS

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I have never heard of a magnetic dial indicator. I will look that up later and its usage. But one thing I was messing around with few weeks ago is trying to figure out if some of the safety features were screwing up the engine and then since I had constant spark I thought no issue with the safety features, but just tonight the idea of disconnecting the kill switch off the ignition coil seems pretty simple to do and could have a major impact on this hunting and surging. So so I absolutely will do that first and foremost tomorrow and see if it makes any change with this hunting and surging issue. I don't think you originally said that, but either way I'm putting it out right here and I hope it's just that simple.

Jim
Best of luck to you
 

dwzkd

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To check for Governor issues. hold the throttle shaft (at the carburetor) against the throttle set screw (low idle), then start engine. If you are seeing hunting at low idle (without holding the throttle shaft) then you should be able to just hold the throttle shaft against the set screw. Otherwise, slowly rotate the throttle shaft to increase speed. You should be able to hold it steady and achieve a stable speed (without hunting) if it is a governor issue. NOTE: be careful with this test as you can easily overspeed the engine if you move the throttle too fast and hold it at a high position. If it is not a governor issue, you will still see hunting if you hold the throttle shaft steady.
 

JimP2014

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To check for Governor issues. hold the throttle shaft (at the carburetor) against the throttle set screw (low idle), then start engine. If you are seeing hunting at low idle (without holding the throttle shaft) then you should be able to just hold the throttle shaft against the set screw. Otherwise, slowly rotate the throttle shaft to increase speed. You should be able to hold it steady and achieve a stable speed (without hunting) if it is a governor issue. NOTE: be careful with this test as you can easily overspeed the engine if you move the throttle too fast and hold it at a high position. If it is not a governor issue, you will still see hunting if you hold the throttle shaft steady.
Thanks for this. You did not waste words I will be checking this out.
Jim
 
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