This is a B&S 20hp v-twin engine on an Ariens model 936042 riding mower. If the mower sits for a week or so without running, it takes several seconds to get it started. I don't want to seem paranoid, and if this is normal then I apologize now. It runs very well after it starts, and when it's warmed up, it starts right away.
I'm sure not one of them smarter guys here on the board but it sounds to me like everything points to your battery, although you don't mention how old it is. If it were me, I'd either put a battery booster on it, or jump it with another 12V battery and see if there's any difference. If it cranks better and starts better....time for a new battery. And quite honestly, "If the mower sits for a week or so without running, it takes several seconds to get it started" that doesn't sound abnormal.
Thank you, sir for your response. The battery is not quite a year old, and it spins the engine over just fine. It seems more like the carb is empty. I don't have a fuel shutoff valve in the fuel line. Been meaning to get one, just haven't got around to it yet.
Thanks. Yeah, the choke is working. I have checked that.
Well, I don't exactly "love" E10, but ethanol free gas is not easy to find around here. I've looked, and I did locate some at a station that is about a 45 minute drive from me. Here it's about a dollar more a gallon. According to the manual for the tractor, it's designed to run on E10. Is that a problem with the mower?
E-10 if left inside the carb say over winter will eat the aluminum body up. Longer it sits with water the worse this all is. E-10 is a nightmare on carbs. And a lot of carbs now are no longer made.
Best to use 100% gas if at all possible. Start hoarding today.... LOL
The reason for the engine info is we are talking about the engine instead of the tractor model number and with correct engine info we can then determine which of the Briggs twins you are referencing.
When a lawn tractor sets for 2 weeks without being started i kinda expect what you are describing. (especially if it has a pulse type fuel pump) requires the engine to be cranking to send gas to the carb)
What I do to reduce the crank time so as to help save the starter and battery.
The starter is suppose to not be cranked over about 5 seconds then rest for awhile. Long crank times ruins both the starter and the Bendix gear.
If I know the choke butterfly on the carb is applying a choke and it still has long crank times I take precautions against backfire
AND
I have a small squirt bottle with some gas and I remove the breather and give it a SMALL prime of gas into the carb throat. (small=spoonfull or less)
Best to have the eq outside the building when priming in case of backfire.
If you ever see a backfire and flames in the carb throat just keep cranking the engine to suck the fire inside.
Summary:
If you know it's being actually choked try giving it a little prime of gas.
What you describe is normal on some eq.
A low pressure (2 psi max) electric fuel pump will reduce the long crank times on some eq. (but most RELIABLE ones are around $60
You need to try the prime thingat first so as to see if getting gas is the issue and make sure your choke butterfly on the carb is actually operating.
The low pressure pump can be installed by itself or can be installed before the pulse pump. The electric pump does not run all time and is low current drain therefore it's not an issue for your battery charging system.
You will see some Amazon 12v low pressure pumps for $20 or less. I have no experience with the $20 and less China/Amazon and I would not trust such.
I cannot refer to to an exact brand and model of pump.
Download and READ your engine manual. Make sure it's for YOUR engine. Read it again. Lots of good tips in there like cleaning the cooling fins yearly and say after 5-10 years de-carbonize the cylinder/s. Last two hardly never get done.
I do have the manual, which is where I got the numbers from.
As for the cooling fins, yes I do clean them yearly. However, I have not decarbonized the cylinders. How is that done?
I do have the manual, which is where I got the numbers from.
As for the cooling fins, yes I do clean them yearly. However, I have not decarbonized the cylinders. How is that done?
Pull the head. Clean the head of carbon. Same for piston face and valves. Get behind the valves too. New head gasket. LAP THE HEAD AND BLOCK FACE. Check for head flatness.
OK, I checked the valve lash, and both cylinders needed adjusted. They were tighter than the factory specs call for. Those were all adjusted to .005. The spark plugs were also gapped a hair too big, so those were adjusted, also. I didn't start it yet because the gasket sealer needs to set up.
I seriously doubt that the impulse pump is the problem considering that near 1/3 of the tractor style mowers run gravity feed .
Impulse pumps are very robust and very reliable in the 12 years I have been running my service business I have needed to replace only 1 failed pump.
OTOH I have replaced over 100 x 50' rolls of fuel line because what was there was hard , split , cracked, delaminated or otherwise would not make a proper seal against a spigot .
As far as I can see there is no real problem.
Modern lean burn mower engines do not start the instant you touch the key and it is more likely stale fuel
Only gases burn
So to start you first have to get fuel into the cylinder as droplets from the carb then some of those droplets need to turn into a gas so the spark can ignite them
All engines are harder to start when cold for this reason which is why we have a choke on a carburettor engine .
Lots of things will make it harder for an engine to start cold
Simple things like running an oil that is too light so it gets too thin thus drains from around the rings as the engine cools so when cold there is not enough oil around the piston & rings to make a proper seal.
Same things happens if the engine gets too hot.
Altitude makes a difference
Humidity
Age of the fuel & how it has been stored as the gasses required for initial will vapourise at room temperature and can all evaporate out of old or badly stored fuel .
Thanks Bert. The pump is still good, so I'm not going to replace it. The fuel is fresh. I fill the tank each time I mow. The gas can was filled with new fuel a few days ago. It's in a sealed container. About the only thing I haven't replaced as far as the fuel system is concerned is the fuel line from the tank to the filter. From the filter forward it's a new filter, pump, and line. I guess I should replace the line from the tank to the filter, just not sure how to access the line at the tank.
Just because the fuel is fresh from the service station that does not mean the fuel is fresh or even the right blend for the season.
Nine times out of ten a hard start from cold is the choke not being 100% closed .
And remember it is a carburettor engine not a fuel injected engine like your car has
Auto engines are now required to start within 2 crank shaft revolutions because of EPA regulations which is why they use very thin oils now days .
I really do not think you have a problem unless you have to crank the engine till the battery goes flat
No, it's nothing like that. Not even close to draining the battery. Just was trying to be sure it wasn't a problem, since I had a slight backfire going on while idling. I adjusted the valves to the tolerance called for in the manual and adjusted the gap on the spark plugs. I haven't started it yet to see if that helped. This is a 14 year old mower, but I can't afford to get a new one just yet. So I have to keep this one running the best I know how.
