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Working on a Poulan Pro with 19 hp briggs motor. When I start hit the key, it turns about one rev. and stops, then another turn and stop, eventually it does start. It runs fine otherwise. I have replaced the starter, no improvement. So I ran a 6 gauge wire from the battery to a solenoid, then the starter. Still no improvement. Battery is fully charged, and brand new wire to the new starter. I'm stumped, any ideas?

Did you check the condition of the negative cable and the negative cable to chassis ground connection? This ground connection needs to be very clean or you will not be able to get good current flow. If it is good, I would be checking valve clearancestors.

When was the last time you adjusted the vavles? And while adjusting the valves make sure the intake rocker is being slight at TDC Compression. If no ACR bump then camshaft has failed.

Poulan Pro????
I've got a chainsaw with that name but it does not use a briggs engine unless Wilbur installed a replacement engine.

What is the model, type and code of the engine on your Poulan Pro?????

Yes there are Poulan Pro riding mowers. I got four different models under my shop's wing.

StarTech said:

Yes there are Poulan Pro riding mowers. I got four different models under my shop's wing.

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I have worked on a couple of Poulan Pro riders. If wiring and battery are good, and no voltage drop, then most likely the valves need to be adjusted. Just like has been mentioned.

What is the model, type and code of the engine on your Poulan Pro?????

Valve adjustment doesn't seem to be it. I verified TDC on the compression stroke, and adjusted both valves, no improvement. Both valves seem to be fully opening, when I spin the motor the valves open to where the spring retainer is about even with the valve cover flange... Any other suggestions?

What is the model, type and code of the engine?

Model 33R877 Type 0009 C1 Code 160404ZD

Did you adjust the intake valve per the Service manual at 1/4 inch past TDC of the piston?

If you did this and your set the intake valve at .0025 at 1/4 inch past TDC of the piston and it still hangs insert a feel gauge under the rocker arm so as the clearance becomes .0005 to .001 and test crank. (do not adjust just insert a feeler gauge so as to reduce the intake valve lash and check the crank)

Doing this test is checking the condition of your Automatic Compression Release (ACR) so as to get an idea if it's broke or just worn down somewhat.

Do you mean the piston down 1/4" in the cylinder? I will try as soon as you clarify....

Yes. Move the piston, up on the compression stroke, until you get to TDC. Continue moving the piston forward, NOT BACKWARDS, until the piston drops 1/4”. Now you set the valve clearance. I do one valve at a time. When I complete one valve I rotate the piston through four complete cycles and then recheck the clearance. If it is off, start over, proper clearance do the other valve. Other techs use different procedures, but we all end up in the same place.

That did get it spinning normally. Guess I need a cam shaft kit

Don’t understand the last post???? Why do you need a cam kit?

Lol

Was that not a test for the ACR? The ACR doesn't appear to be working...

No, what you did was set the valve clearance properly. That procedure had very little to do with ACR. As Star stated, when you rotate the flywheel you should see a little intake valve movement as you approach TDC. If you see movement your ARC is probably working properly.

You might watch some you tube videos of how to set the valve lash on a Briggs 33 series engine.

Here is a link to one video: I suggest you watch more than one video.
Also note that you are turning the flywheel CW when going past TD on the compression stroke..
Set the intake valve lash at a snug .0025.
If you watch the videos carefully you may see the intake valve rocker arm do the slight dip JUST BEFORE the piston reaches TDC. If you do not see the dip just go ahead and adjust the lash at .0025 install the spark plug and test.
Let us know the results?

If the engine starts spinning normally install the valve cover see if it will crank, start and run.

RichF28 said:

Working on a Poulan Pro with 19 hp briggs motor. When I start hit the key, it turns about one rev. and stops, then another turn and stop, eventually it does start. It runs fine otherwise. I have replaced the starter, no improvement. So I ran a 6 gauge wire from the battery to a solenoid, then the starter. Still no improvement. Battery is fully charged, and brand new wire to the new starter. I'm stumped, any ideas?

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Check your valve lash

RichF28 said:

Working on a Poulan Pro with 19 hp briggs motor. When I start hit the key, it turns about one rev. and stops, then another turn and stop, eventually it does start. It runs fine otherwise. I have replaced the starter, no improvement. So I ran a 6 gauge wire from the battery to a solenoid, then the starter. Still no improvement. Battery is fully charged, and brand new wire to the new starter. I'm stumped, any ideas?

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Check the voltage on the starter when you try to start the engine it should be 11 volts or higher if not try jumping the solenoid large wires if engine turns over replace solenoid
.

RichF28 said:

Working on a Poulan Pro with 19 hp briggs motor. When I start hit the key, it turns about one rev. and stops, then another turn and stop, eventually it does start. It runs fine otherwise. I have replaced the starter, no improvement. So I ran a 6 gauge wire from the battery to a solenoid, then the starter. Still no improvement. Battery is fully charged, and brand new wire to the new starter. I'm stumped, any ideas?

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RichF28 the B&S single cylinder OHV engines are notorious for being hard to start when the valves get out of adjustment or the decompression release fails to work. Simple test take the spark plug out put some thing over plug wire so the spark won't ignite any gas, then sit in the seat and turn the key if it spins over quick with limited compression reset the valves and try again with the plug in if its still a hard start its the decompression relief on the camshaft. Good luck. I just waited on a customer with the same issue.

RichF28 said:

Working on a Poulan Pro with 19 hp briggs motor. When I start hit the key, it turns about one rev. and stops, then another turn and stop, eventually it does start. It runs fine otherwise. I have replaced the starter, no improvement. So I ran a 6 gauge wire from the battery to a solenoid, then the starter. Still no improvement. Battery is fully charged, and brand new wire to the new starter. I'm stumped, any ideas?

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Usually its the valves not set right

Put a battery's Neg connection rite to the engine block and touch the Pos directly to the starter. This eliminates the wiring within mower. If it turn fast then you have a bad ground or Pos connection somewhere.

You need a new cam. Compression release is notorious for breaking on that motor. Its built on the cam. One revolution an and stops is a dead giveaway.

Just a question but are all the compression release valves built with the non adjustable valves? Or did they come with valves that need to be set also?

Nearly all small engines with ACR are one with solid lifters (tappets) and solid type push rods. And yes they all have adjustable rockers.

Now with hydraulic lifters usually don't have adjustable rockers as the lifters are self adjusting. Also the push rods maybe solid of hollow depending on the engine's design.

How come kohler has most solid lifters without the ACR?

because mower starters are low power devices , designed to stall if the engine is hydrolocked rather than blow the gaskets or bend the pushrod or crack the head.
You have to remember than vertical shaft engines are made exclusively for mowers and mowers are very price sensitive .
Thus they are made as cheap as possible so all of the parts are as weak as possible , because weak is both light & cheap .
A slightly stronger starter can overcome the compression of the engines and Kohler use a stronger starter in their engines than b & S do .

I can somewhat agree to that....is something other then fuel creating it to hydrolock IF......the fuel plunger fails?

smalltimerpm said:

I can somewhat agree to that....is something other then fuel creating it to hydrolock IF......the fuel plunger fails?

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Than not the purpose the fuel solenoid on the carburetor. Now the float needle valve and seat can cause fuel leakage. But fuel solenoid is there only to block the main nozzle so the engine starves for fuel and quits.

To explain it fully
1) EPA decided that mowers must meet the same hydrocarbon emissions as cars
2) Overflow & float bowl drains removed , not that many mowers actually had them
3) float bowl vent moved to a hole near the top of the engine flange
4) solenoid fitted to main jet .
5) manifold & carb required to slope into the engine so any spills go into the engine & not to the atmosphere

So when the float bowl needle valve fails the float bowl fills to the vent hole then the fuel fills the vent tube and pours out the end onto the manifold .
From there it dribbles down the manifold & into the cylinder

next time you have a carb apart blow some goop through through all of the holes in the body and see for yourself where it comes out .
Then you might understand what is happening .