Intermittent Sputtering

[Modify Man]

I have searched through many web sites for a similar issue and finally realized that it was time for me to post this issue with the hope of finding the problem and a solution.

Been using a Craftsman YTS 3000 for pulling a trailer around the property. The deck is removed.
Noticed that when I go full throttle in high gear, the engine would sputter for a couple seconds. Sounding like it is about to run out of gas.
Then it would continue fine for about 8 seconds. Again, the engine would sputter for a couple of seconds...
I thought that it was caused from the bumps at high speed.
I pull back the throttle a bit and it sounds fine. Just moves slower.
Used it to go work on a generator about a half mile away. Thought for sure that when I hit the smooth asphalt it would not have the sputtering issue.
Sure enough it does the same thing.
With the first part being a hill I thought for sure it was going to die. But it made it up.
Level surface did not matter. Coming back down it didn't sputter.
Checked fuel filter, pump and looked for air leaks. Ran it without an air filter and still sputters. The carburetor is almost 2 months old so I don't think its that. Run open throttle in neutral and it runs fine.
So what is going on?

 

[slomo]

Sounds like a partial dirty main jet in the carb. Or pilot circuit the same. Should be running on the main jet at half to full beans.

I would do a full tune up.

Clean or replace with OEM carb.
Flush the fuel tank out.
Replace fuel lines and filter.
Install a fuel shutoff valve.
If installed, check or delete carb solenoid.
Valve clearance adjustment YEARLY. This is in your engine manual.
Clean cylinder cooling fins YEARLY. Again in your engine manual.
Make sure the oil is EXACTLY on the full mark, not over or under. Check every time you use the tractor prior to using.
Air filter tip top. Install a foam pre-air filter if you can get one for your engine. Put some SAE30 oil on the foam pre filter. Squeeze excess oil out into a shop rag.
Little silicone grease on the air filter gasket area to stop grit from sneaking under the gasket getting inside the engine. Get anal about your air filter and cooling fins.
Clean the spark plug or replace.
De-carbonize the cylinder/s every 2-3 years. Again in your engine manual.
Slather on some Turtle Wax Super Hard Shell on the paint.
Little tire dressing on the tires.

Wear safety glasses and hearing protection at all times. Grandfather lost an eye using a trimmer. Shower shoes and Crocks are to be left in the dumpster when mowing.

slomo

 

[Modify Man]

Yeah. So here is what I have done since I resurrected this machine.
Cleaned it. And I mean...cleaned it good.
Removed the steering column cover to lift the body, pull the gas tank and have access to the top of the hydrostatic transmission.
Wasn't able to get that rubber seal off but at least it can now properly air cool.
The nipple that goes to the charcoal canister was broken off the gas tank. Not sure but, that may have been me when removing the tank. Replaced it using a 1/4" ID hose barb X 1/8" MIP brass fitting. Finding the correct tap was a lesson in MIP.
Wire wheeled any rusted parts before reassembly. Greased all parts of the steering column and the blades engagement lever.
All new fuel and emission hoses.
Checked the emission one way valve.
Tested the fuel pump...and replaced the fuel filter. (Still only fills half way.)
Replaced the steering wheel with a cushiony style and the crACked seat from a "parts mower".
Also borrowed a couple of its rubber wheel cover caps.
Put on some new heavy duty mulching blades.
Replaced all the 3 idler pulleys. New Drive belt
Changed oil and filter. (Used a water bottle with a 56 oz. line marked on it.)
New carburetor. (old one...broke off the mixer screw) Oh. And I made sure I ordered one that had a tool for adjusting it...it was not the correct tool. Ground the head to a single D style.
New starter solenoid, Battery, disconnect switch, and light bulbs. (Removed the lenses until I can find a solution to re-clear them.) Cleaned the light switch, ignition switch, both interlock switches and the ammeter.
Rewired the head lights switch to the ignition switch side of the ammeter...?
Removed the 2 spacers under the seat and tightened the nut enough to keep the seat switch on...?
Removed the bypass wire from the plug that belongs in the brake/clutch interlock switch...?
Cleaned/blew out the air filter...do that regularly. Need to oil the foam though.
Cleaned the air filter to canister.
Spark plug...Greased zerc fittings.
Adjusted the valves, brakes and drive shifter.
Made a trailer hitch which includes rubber washer and a retainer spring clip for fast hook-ups and noise control.
Need to clean the wheels around the tire beads and get those all to seal good.
And...what you said.
The fuel tank looked really good. But after drilling and tapping into it...well, it got some attention.
9 weeks ago I believed that thing was only good for some parts...And now I like it better due to its extra leg room.

Got to find that sputter issue. I'm actually hoping that it is a simple carb issue.

Oh yeah...and the deck has a cracked weld on one of its brackets-mounting-attaching thing.
Time to brush up on my intermittent neglectable welding abilities.
And should check the bearings in the Mandrel Housing. Search around for some high quality bearings if the existing are not salvageable.
I'm also curious what kind of material that washer is that is between the bottom bearing and the bottom of the mandrel.

One last thing:
The drink holder is useless.

 

[slomo]

Carb clean or replace with a new OEM carb.

Verify carb solenoid is working or simply delete it and never have to worry about it again.

slomo

 

[Modify Man]

*You just had to say that.
Next installment.

The lawn mowers previous owner over filled it with oil and it became a black smoke machine on wheels.
He gave it to my brother for parts and after unloading it, it sat for a few of months.
I figured something was blown due to the over fill.
Dad did that to his push mower. I drained the excess out but it had become...broken Craftsman scrap metal.

9 weeks ago:
It's weed abatement time and we had some big lots to do. One riding mower takes a long time for these large lots. So my brother has a lawn mower guy come look at what we have. He thinks the black smoker has just to much oil.
Draining enough oil to satisfy the recommended fill requirements. He cleaned the spark plug and got it to perform its black smoke presentation one last time. And it proceeded to run. I drove it around some and mowed down some weeds. It did have a grinding noise when in neutral. But it was running well enough to mow down some weeds.
Also, it didn't have a starting solenoid or a battery, so it was started directly from a spare car battery to the starter.
Some new blades were ordered for it and they finally arrived that morning we were starting to take down the weeds.

(Yeah. Still no battery or solenoid but got to have something that will cut those damn weeds.) Loaded up the 2 running mowers into the back of the dump trailer and we're off.

The first lot we couldn't use the riding mowers.
The next lot was 2 acres and have always used a riding mower. Took some time especially when the weeds were some times close to three feet tall.
Unloaded the mowers. Using ramps going up and down a dump trailer is something to pay close attention to. Especially when one of the mowers brakes had stopped working.
So the first little 18 hp mower starts mowing but the big 21 hp, no solenoid/battery, mower started acting up.
Had to just push it out and down the ramps.
So I'm thinking, "It has got to be the carburetor. It was never cleaned and I suspected that this could happen but, that was not my project...yet.
I decided to just do it myself. So I went back to the house to get what I needed hoping I could get it to run good enough just for the day. After I had it reassembled and back on the mower I attempted to get it running right...well, good enough.

I eventually took a break to help with a tree thing but first put the car battery on the charger. I was constantly having to restart it because it would always eventually die. There was something not working right.
I returned to try once more to get that mower to run good enough .
Jumper cables on and it oomphed... and it oomphed.
The battery has more charge now than when I stopped earlier. "Did the engine really just crap out?"
I pulled the spark plug to see if I could turn it by hand and guess what??
Gasoline poured out. Called it for the day. It was hot, dusty and frustration had taken its toll.

So! I later figure out that the solenoid was not functioning.
Normally the machine should never had started. But it did and was very consistent in its running inconsistently.
So apparently the carburetor solenoid also was not sealing properly and of course not opening when the mower was on.
*Under the right conditions, a vacuum can occur from the engine to the gas tank. When this occurs gasoline is pulled right into your motor. Another function of the carburetor solenoid is preventing this from occurring. Of course if it's not closing properly, this could still happen...or lets say someone got off the seat, left the key on and walked away.

 

[Born2Mow]

So my brother has a lawn mower guy come look at what we have. He thinks the black smoker has just to much oil.

That "lawn mower guy" is clueless.
The very first thing you learn on the very first day is: "Black smoke is Rich fuel condition. White smoke is burning oil."