Briggs 18.5 hp Wont Run

smhardesty

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And then this is done and the engine come into my shop it gets a new solenoid and customer gets the bill for being stupid. Sorry but is how I feel about it but it is one stupid thing that can fixed. Other stupid things can't be fixed.

Oh btw those fuel solenoids are cleanable.
I specified it was a poor man's fix and clearly stated it wasn't the recommended way to fix it. He had stated he already cut the wire off the solenoid to try and fix his fuel flow problem. I was simply offering what I'll call the correct way to do a poor man's repair job and a brief explanation that cutting the wire wasn't going to solve a sticking solenoid plunger. No, I wouldn't recommend that to everyone, but it will solve his problem on the cheap, whereas cutting the wire had the reverse affect on the plunger.
 

bertsmobile1

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There is a solenoid shut off on the bottom, but I cut it off because the wire wasn't giving a reliable connection. I did notice it blowing some gas back and found out that means the valves may be out of whack. Do you know what the valve clearances on this engine are?
0.004" both sides
 

kkjfjns2014

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If it was getting too much gas it would be running out of the carb, the float may be stuck or is there a solenoid shut off under the bowl ? Post a few pics if you can

And then this is done and the engine come into my shop it gets a new solenoid and customer gets the bill for being stupid. Sorry but is how I feel about it but it is one stupid thing that can fixed. Other stupid things can't be fixed.

Oh btw those fuel solenoids are cleanable.
I didn't cut the wire I cut the plunger on it, I'm not a total idiot lol.
 

kkjfjns2014

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That Solenoid needs 12volts to open and let fuel into the machine , if you cut the wire , there's your problem
Also the Solenoid keeps it from backfiring when you kill the ignition
If you have compression and it runs , doubtful you have a valve clearance issue
I cut the plunger on it not the wire.
 

kkjfjns2014

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That Solenoid needs 12volts to open and let fuel into the machine , if you cut the wire , there's your problem
Also the Solenoid keeps it from backfiring when you kill the ignition
If you have compression and it runs , doubtful you have a valve clearance issue
It would only run with the choke on and I noticed it blowing some gas back out of the carb last time I tried starting it. Local mower man suggested valve adjustment as the next step.
 

kkjfjns2014

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I cut the plunger on it not the wire.
Sorry everyone I realize how I worded that made it seem like I cut the wire and not the plunger on the end of the Solenoid. I just did it because no matter how I tried to put the wire in and get it tight I could hear it clicking up and down every time you barely touch the wire so I imagine as you're bouncing through the yard it would probably be cutting the gas off intermittently. I'm going to check the valves tonight and report back what I find. Thank you all for your help thus far.
 

kkjfjns2014

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0.004" both sides
These are the specs I found online for this specific engine model. Does it seem accurate? Or should I just roll with the .004?
 

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Forest#2

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.003 intake
.005 Ex

Intake is the main one to get set at .003-.005. go for .003 because the ACR (Automatic compression release) is on the intake cam lobe of the valve
BUT
You say the engine cranks fast which indicates that the valve lash may not be the main problem YET. (but can be easily checked)
You can see you tube videos of how to do such for your Model Briggs))

You say in post #7 when it's cranking fast you see gas blowing back up into the carb throat. seeing gas blowing back is normal on that Model engine when the engine does not start and it's getting too much gas into the carb float due to flooding.

The reason you see a spit back of gas is the ACR momentarily blows excess gas back into the carb throat and then sucks it back just before TDC for a run. (sounds strange but true)
Pull the spark plug and see if it's wet. dry it off and re-install then
turn off the gas supply to the carb set the throttle to high rpms, no choke and crank engine and it will probably start and run for little while. If you then see it doing same thing again the carb bowl is getting too full. Note that I did not say it's the needle/seat. If it's a Nikki carb the little rubber gasket in the very top of the carb above the plastic piece is bad (it seals above/before the needle/seat or the needle/seat is bad.
 
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Forest#2

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.003 intake
.005 Ex

Intake is the main one to get set at .003-.005. go for .003 because the ACR (compression release is on the intake valve
BUT
You say the engine cranks fast which indicates that the valve lash may not be the main problem YET.

You say in post #7 when it's cranking fast you see gas blowing back up into the carb throat. seeing gas blowing back is normal on that Model engine when the engine does not start and it's getting too much gas into the carb float due to flooding.

The reason you see a spit back of gas is the ACR (Automatic compression release) momentarily blows excess gas back into the carb throat and then sucks it back just before TDC for a run. (sounds strange but true)

Doubtful it's a valve lash issue if that model engine is cranking fast.

Most likely the engine has weak ignition, flooding or wrong or bad spark plug or weak magneto.

You seem to indicate that it was doing the same thing before you replaced the carb so I would think about ignition.
 
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