Yardman push mower just won't start!??

[dart451]

Have a Yardman pushmower that I'm working on, 11A-54MY255, ser.1L196K20283. It was brought to me cause the guy couldn't get it started. When I spray some starting fluid in the carb, it starts right up. I soaked the carb in carburetor cleaner, put it back together...still wouldn't start. It has a pull cable for the choke which works perfectly but it won't pull fuel to start. I put a new carburetor on...no change. I removed fuel line, there was an inline filter I removed, thought it might be restricting...Nope! Checked compression, getting over 60psi on first pull. When I manually choke or use starter fuid, engine starts easily, runs if you have it mostly choked, (choke cable). After it warms up, runs beautifully without choke. So, I'm not sure what else to do!? Spark plug is good and I cleaned it. Any words of wisdom that could help me with this darn mower?

[bluemower]

here are a couple of questions:
1. what is the difference between the pull cable for the choke and manually choking?

2. what are you seeing when using a gap spark checker such as the Briggs?

3. What is the condition of the flywheel key?

4. how old is the fuel?

5. Exhaust valve adjustment?

[dart451]

Ok, manual choke is holding a rag or covering the carburetor throat to choke. However, this works better but not much.

Have not tried a spark checker...most of the time I can't see the spark when I use it so I usually don't use it.

Have not checked the condition of the flywheel. I guess because the engine runs so smooth when it warms up, I didn't bother to check.

Have fresh fuel that I put in the tank...tank was empty when I got it.

I have not checked the exhaust valve adjustment...but I did think to check it after I posted this...

[dart451]

Checked the flywheel, the keyway is perfect. I can't seem to figure out what engine this has so I can look up the valve clearance though! Anyone know where to look? I can't seem to find the clearance specs on the 11A-54MY255.

[dart451]

Valve lash is fine...intake was a bit wide is all...can't think of anything else to check.

[RoyM]

It is likely a Chinese Powermore engine built for MTD. .003-.005" on the intake, .004-.006 exhaust should get you going.

[dart451]

Think I'm gonna have to give up on this one! Tried everything I could think of and all the things you guys have suggested...

[KE4AVB]

Do you want to try reading through the service manual for the P65? Maybe something in there that might help. I can PM/email a link to a temporary download of the file on my One Drive.

Now I did ran into a Honda carburetor that I couldn't whatever was in it out and I ended having to put a carb on it. It was taking 4 pulls to start cold and pull until your arm felt like it was going to fall off when hot.

[bgsengine]

I put a new carburetor on...no change.

So? New does not mean Good. Could still be a bad carb (or wrong one, wrong jets, etc.)

Your symptoms are exactly like a machine that is jetted or adjusted too lean. On top of that I'd agree to check valve clearance (or do a leakdown, better yet - a burned valve or valve not seating could cause that too) what you gotta do is figure out which system for sure is the cause - just assuming spark is good (could be a bad plug wire or bad electrical connection) and assuming 60 PSI is good (It's borderline low, assuming you check compression correctly) all examples of what could be a problem that leads one to think carburetor is bad..... You got to make sure it actually is fuel system, if you can't be 100% (No guessing allowed - got to VERIFY spark , compression, exhaust are good, not just assume so because it runs good once warmed up... notably valves could be an issue there) then you got to take steps to verify (not guess) that each part of the system (Suck, Squeeze, Bang, Blow) is within proper operating parameters.

[dart451]

Ya, I guess it could be the carb...I did check the valves, intake was pretty wide but I have them set now...no change. I think the next thing I'll try is put another tank and fuel line on, see if it makes any difference. I haven't done a leak down test but I can do that. I also notice...when I do start it (with starter fluid) the engine smokes a bit for about 20-30 seconds till the smoke goes away while running. Perhaps the oil rings aren't holding up very well...but it does clear up...