turbofiat124
Well-Known Member
- Joined
- Mar 23, 2011
- Threads
- 83
- Messages
- 288
I encountered a weird issue with my backup Troy Bilt riding mower the other day. I don't have the engine model number if that matters but it was built in 2009 and is 17.5 hp Briggs engine.
While waiting on a new deck spindle for my Craftsman (Husqvarna), I got it out for the first time since fall. I don't really like this mower because I'm too used to the hydrostatic transmission on my Husqvarna and it's awkward having to come to a complete stop to speed up and slow down around trees and shrubs.
Initially it was running OK. But over time it got to where it sounded a bit rough at times. Then I shut the engine off to chit chat with my father and afterwards I noticed fumes coming out of the muffler. I thought the thing was going to burst into flames! Then I noticed gasoline starts filling the neck of the air cleaner. I've seen this happen before, a stuck float valve.
So I took the carburetor off and pulled the fuel bowl off and discovered the float would not pivot. I noticed the float is made of a cheap white plastic material instead of brass.
So I removed the float and float valve and cleaned them and passages with carburetor spray cleaner. I put the carburetor back together and tested it upside down and so forth to make sure the float was now working. But that was not all I had to do. The crankcase was full of gas and the spark plug was carbon fouled from running rich. So I had to change the oil (which it needed anyway) and I bead blasted the spark plug. Yes I realize your suppose to replace spark plugs anytime something happens but I bead blast my plugs and recheck the gap. It's worked fine for me for years.
While I was at it, I also replaced the fuel hose and fuel filter.
So I finish my mowing and put the mower up.
So I get it back out a week later and for some reason the mower will turn over but not start. I checked the oil level to make sure the float valve is seating. Level is fine. I get out some starting fluid and it fires right up and idles and runs fine otherwise. I let it run for awhile, shut the engine off and it once again won't start. I check the choke operation while running and the engine bogs down with the choke on so I know the choke is working.
So I decided to check the spark plug. It looks fine to me but I wondered if the spark plug has anything to do with this problem.
I pulled the spark plug out of my 21 HP B&S engine. Now the mower fires right up!
So why would the engine require starter fluid to start on one spark plug but not another? Even thought it looks clean could it be getting weak causing a weak spark?
If the spark plug is not the issue, then what other issue could it be? I made sure all the O-rings were in place when putting the carburetor back on. My other guess would be an air leak between the carb and engine.
The one I pulled from the 17.5hp engine was a Champion RC12YC. The one I pulled from the 21 HP engine was a Champion RC12YZ or XZ or something (sorry didn't write it down). The only difference I could tell between the two was the one from the 21HP engine had a pointy electrode that looked like looked like on a Bosch Platinum or Iridium type plug. Another ever seen this type of plug? It's the same spark plug that came with the mower also around 2009 to 2010. What's the difference between this plug and RC12YC?
I went to O'Relieys for a new spark plug. While he had my engine pulled up on his computer, there was this one particular spark plug that caught my eye. I can't remember the plug but seems like it was made my Champion. This spark plug was $73!!! Why would a spark plug cost that much? And I thought those Autolite plugs for Ford Modular V8 engines at $14.00 a pop X 8 were expensive.
I was in a bit of a rush so I didn't have time to write it down but next time I'm in there I'll write the plug number down to investigate what is so special about it. I tried looking on their website but it's a bit hard to navigate unless your looking for a park for a specific vehicle.
While waiting on a new deck spindle for my Craftsman (Husqvarna), I got it out for the first time since fall. I don't really like this mower because I'm too used to the hydrostatic transmission on my Husqvarna and it's awkward having to come to a complete stop to speed up and slow down around trees and shrubs.
Initially it was running OK. But over time it got to where it sounded a bit rough at times. Then I shut the engine off to chit chat with my father and afterwards I noticed fumes coming out of the muffler. I thought the thing was going to burst into flames! Then I noticed gasoline starts filling the neck of the air cleaner. I've seen this happen before, a stuck float valve.
So I took the carburetor off and pulled the fuel bowl off and discovered the float would not pivot. I noticed the float is made of a cheap white plastic material instead of brass.
So I removed the float and float valve and cleaned them and passages with carburetor spray cleaner. I put the carburetor back together and tested it upside down and so forth to make sure the float was now working. But that was not all I had to do. The crankcase was full of gas and the spark plug was carbon fouled from running rich. So I had to change the oil (which it needed anyway) and I bead blasted the spark plug. Yes I realize your suppose to replace spark plugs anytime something happens but I bead blast my plugs and recheck the gap. It's worked fine for me for years.
While I was at it, I also replaced the fuel hose and fuel filter.
So I finish my mowing and put the mower up.
So I get it back out a week later and for some reason the mower will turn over but not start. I checked the oil level to make sure the float valve is seating. Level is fine. I get out some starting fluid and it fires right up and idles and runs fine otherwise. I let it run for awhile, shut the engine off and it once again won't start. I check the choke operation while running and the engine bogs down with the choke on so I know the choke is working.
So I decided to check the spark plug. It looks fine to me but I wondered if the spark plug has anything to do with this problem.
I pulled the spark plug out of my 21 HP B&S engine. Now the mower fires right up!
So why would the engine require starter fluid to start on one spark plug but not another? Even thought it looks clean could it be getting weak causing a weak spark?
If the spark plug is not the issue, then what other issue could it be? I made sure all the O-rings were in place when putting the carburetor back on. My other guess would be an air leak between the carb and engine.
The one I pulled from the 17.5hp engine was a Champion RC12YC. The one I pulled from the 21 HP engine was a Champion RC12YZ or XZ or something (sorry didn't write it down). The only difference I could tell between the two was the one from the 21HP engine had a pointy electrode that looked like looked like on a Bosch Platinum or Iridium type plug. Another ever seen this type of plug? It's the same spark plug that came with the mower also around 2009 to 2010. What's the difference between this plug and RC12YC?
I went to O'Relieys for a new spark plug. While he had my engine pulled up on his computer, there was this one particular spark plug that caught my eye. I can't remember the plug but seems like it was made my Champion. This spark plug was $73!!! Why would a spark plug cost that much? And I thought those Autolite plugs for Ford Modular V8 engines at $14.00 a pop X 8 were expensive.
I was in a bit of a rush so I didn't have time to write it down but next time I'm in there I'll write the plug number down to investigate what is so special about it. I tried looking on their website but it's a bit hard to navigate unless your looking for a park for a specific vehicle.