@#$%&* B&S. Hard Starting....

[ROUSTABOUT]

The choke is where it's at. Mine is 22 years old and busts right off. It's had a hard life too. I mow bad areas at times, re claim new territory.

 

[Tinhack]

Probably a bad fuel pump or the pulse line to the pump is leaking. Perhaps even an intake manifold air leak.

New fuel pump and pulse tube....

Then it's probably a leaky manifold. If it has the plastic intake manifold, then it's leaking. I had a Sears lawnmower that did that when it was a month old.

 

[WranglerX]

Does it bust right off with carb cleaner or is it still stubborn?

Still stubborn.... But it runs like a banshee once started....

 

[2manyrocks]

Haven't ever tried this, but perhaps an inline bulb primer could be added like used on outboard boat engines? But I'm not sure what you'd actually gain over squirting carb cleaner in the carb as you are already doing except not having to buy carb cleaner.

 

[gstrom99]

Haven't ever tried this, but perhaps an inline bulb primer could be added like used on outboard boat engines? But I'm not sure what you'd actually gain over squirting carb cleaner in the carb as you are already doing except not having to buy carb cleaner.

Probably not able to "add" the primer bulb thingy. There needs to be a port on the carb for the line.

 

[WranglerX]

UPDATE: Well It just would not start this morning...Would not!!!!!!


So drug it up to shop with my SCUT pulled hood off, used volt meter to check all connection to eliminate every possibility of a electrical issue... Notably fuel solenoid and power to magneto...
Put old spare spark plug on one cylinder and tried to see if I really did have spark at plugs, YEP it actually started on only one cylinder... Tried same thing on other side and same thing ... Have good spark at both plugs and it now starts & runs as it should.... That is, when it is warm and decidedly has fuel...... Going to wait a few days letting it just sit and then try to start it and see what happens.....
Only conclusion is it has/had marginal electrical connection some place and fiddling with it "fixed" it ..... OR with all the spinning up it finally got fuel...

 

[tomplum]

So you should have power to the fuel shut off solenoid, but none to the coils. So in a moment of testing, don't put power to them. Yours would have the fuel solenoid straight down out of the bowl unless the carb was ever replaced. On these you do have to remove the bowl to get at the solenoid plunger and then reinstall. You should be able to feel the solenoid activate when the key is turned to on. One test that I like to do is actually crank the engine with the meter leads in the back of the connector to ensure power is present. All that being said, if you don't feel a solid click, these are known to get sticky and sluggish over time so it would be suspect.

 

[WranglerX]

So you should have power to the fuel shut off solenoid, but none to the coils. So in a moment of testing, don't put power to them. Yours would have the fuel solenoid straight down out of the bowl unless the carb was ever replaced. On these you do have to remove the bowl to get at the solenoid plunger and then reinstall. You should be able to feel the solenoid activate when the key is turned to on. One test that I like to do is actually crank the engine with the meter leads in the back of the connector to ensure power is present. All that being said, if you don't feel a solid click, these are known to get sticky and sluggish over time so it would be suspect.

Begging your pardon but tractor wiring and wiring diagram shows when key is "on" power (12 volts) is applied to fuel solenoid AND magneto coils...

 

[jaxs]

After old eyes couldn't clearly see spark in daylight and the pucker string got weak,I've found this works good checking spark to plugs.

 

[goeduck]

My neighbor gave me a no-name engine 7HP chipper that is harder than heck to pull start (pulls hard). I have a 6 HP air cooled diesel that is easier to pull.

 

[tomplum]

Nope. Maybe the diode is throwing you? There is a diode in twin cylinder harnesses between the ignition coils. When you turn the key off, there is a ground present on that wire. That kills the spark. The rest of the key positions nothing should be present. Power sends the CD in the coils to heaven...
You want battery voltage and a ground present at the carb solenoid in all positions but off. On rare occasions I find that go away when cranking, which isn't helpful at all.

 

[RandyT]

Power sends the CD in the coils to heaven...

Instantly,

 

[WranglerX]

Nope. Maybe the diode is throwing you? There is a diode in twin cylinder harnesses between the ignition coils. When you turn the key off, there is a ground present on that wire. That kills the spark. The rest of the key positions nothing should be present. Power sends the CD in the coils to heaven...
You want battery voltage and a ground present at the carb solenoid in all positions but off. On rare occasions I find that go away when cranking, which isn't helpful at all.

Help a foggy old tired brain.... What is the CD? Do you mean Capacity Discharge?...

Think I found it....

 

[RandyT]

Help a foggy old tired brain.... What is the CD? Do you mean Capacity Discharge?...

Think I found it....

In this case the CD would be capacitive discharge. The older Briggs were inductve discharge but use a hall effect trigger for the spark discharge

 

[jaxs]

Still stubborn.... But it runs like a banshee once started....

Not meaning to be redundant but the starter is turning engine over reasonably fast isn't it? I have to ask because we are running out of possibilities and you did mention something earlier on about "resorting to jump box".
Look at parts breakdown for your engine to see if it has a compression release to ease starting. If it does I suggest adjusting valves. If and when you do adjust valves,be sure to follow instructions regarding whether exhaust valve is adjusted on compression or exhaust stroke,it makes a huge difference.

 

[2manyrocks]

Be very careful to get the exact instructions from Briggs for your specific engine before adjusting the valves. They may instruct you to be at a certain position before or after (can't remember which) TDC.

 

[WranglerX]

Yes it has compression release.... Funny thing is after sitting for 24 hours from last run time, it started ok just fine today.... Still think its a fuel draw issue when carb fuel bowl is dry....

 

[2manyrocks]

If it starts fine when it has fuel, I wouldn't touch the valves.

I literally replaced the fuel line, fuel shutoff valve, fuel filter, fuel pump, tank grommet and pickup tube on my JD Z225 in addition to replacing the engine. And I made sure the vent hole in the gas tank cap was clear.

forgot...are you sure your choke is actually working. Part of my trouble was the choke didn't seem to be working when starting the engine. I converted it to a manual choke with a separate cable and it worked fine for a while.

 

[WranglerX]

This has separate manual choke cable an its verified working..... Still think a small (pinhole) in fuel line and it has trouble drawing fuel becasue the pinhole reduces the amoun of vacuum fuel pump creates... Its those silly bubble showing up in fuel filter that keeps telling me this....

 

[Fuddyduddy1952]

I like these $15 universal 12v fuel pumps.
Solder & heat shrink longer leads on it, lamp cord is fine. Put alligator clips on end (Harbor Freight, etc.). Remove fuel line going to carbs & plug it. Fuel line output side to carbs, inlet side fuel line down into your gas can. Clipped across battery, see how it does.
You'll see if it's a fuel delivery problem.
It's also handy for filling the gas tank.