14SB Experiences. Any ideas?

RalphVa · Sep 6, 2007

I stopped by JD to see if they could test the "igniter" that I'd bought a couple weeks ago, as it had spark but seemed to be off time. This is after I checked the valve clearances after it quit on me with some backfiring and black smoke. (Let it cool a bit, and it ran again for a very short period before just stopping.) The exhaust valve stud was stripped, but the clearances weren't tight. Replace valve gear, made sure valves were moving up and down and set to right clearances. Even removed the flywheel and checked the keyway. Not sheared.

Described this to the technician, and he had the parts people sell me a new spark plug and air cleaner (even though I told them that the air cleaner was pristine clean). Put these on, and it started. So, I put it down to idle and went to get my safety shoes to use it for a while. It quit before I could return with the shoes. Absolutely will not start, even with some starting fluid injected into the air cleaner hole.

Went out tonight and carefully set the throttle cable linkage to make sure the choke went off when selector is returned to "fast". Then removed jets and blew out what I could on the carb. Couldn't get the main jet on top removed with carb in place. Put it all back together and tried it. No fire at all. Put timing light on between plug and lead. It fires. Has spark.

This is totally weird. I've gone through replacing the fuel valve and finally putting a tygon tube from it to the carb. Getting fuel now (before, I'd posted about fuel starvation with a fuel filter in place), with new in-tank fuel filter. The spark igniter quit at one point, as there was no spark. I replaced both the coil and igniter (they were combined on later models). Coil is set at the 0.012" between it and flywheel.

Anyone have any ideas?

Ralph

RalphVa · Sep 24, 2007

I dropped it off at the local P&L repair place. Gave them this note:

Bought at an estate sale last winter (early 2007). Appeared to not have been used much. They had little lawn, and there was a very scruffy, cheap mower in a shed that they obviously used most of the time.

Was full of fuel. Started first pull. Mowed front yard and sharpened blade afterwards.
Continued to start first pull, but after 2 or 3 mowing, it would just die after running about 15-20 minutes. Seemed to have fuel starvation. Put a universal fuel filter in line between on/off valve and carb. Didn稚 notice the carb bowl drain at this point to check fuel supply.
When it died, fuel filter would be dry. Could blow on the top of the tank and get fuel. Checked tank cap and even left it loose a few times. Still would starve for fuel. At one point, I removed the fuel strainer in the tank.
Somewhere along in here, the drive belt wore out. Replaced it.
At times, got tired of forcing fuel and would let it sit. . Other times, it would be getting fuel but wouldn稚 start. Would start after sitting a while or next day.
At one point, letting sit overnight, it wouldn稚 start. There was no spark.
Bought new on/off fuel valve and fuel tank strainer and spark coil, setting it at the 0.012 clearance from flywheel. Wouldn稚 start. Discovered the 妬gniter? Bought new igniter. Started up fine now but still suffered fuel starvation.
Decided fuel filter was problem. Couldn稚 get air bubble completely out of it. Replaced line with see-through tygon one. Good fuel supply.
Mowed for about 30 minutes. Suddenly, engine started backfiring and finally died, after emitting black smoke amid some backfiring. Let sit. Started, but ran only about 5 minutes.
Checked valve clearances. They weren稚 tight, but discovered stud on exhaust valve OHV assembly was stripped at adjustment point. Replaced stud and set clearances to 0.005?
Engine started, but seemed to a little out of time and was making pinging sounds.
Described above to JD technician. He suggested that the flywheel keyway could be stripped. Took flywheel off. No problem.
Described above to another JD technician. He zeroed in on the 澱lack smoke (that had occurred for maybe 2 seconds time) and showed me the throttle cable adjustment to ensure it went off choke when put on 途un? Recommended I buy new spark plug and air filter (but air filter; I thought, was pristine clean).
Engine started with new spark plug and air filter and ran in time. Cut it back to idle to go get my steel toed shoes to mow some. Engine quit before I got back with shoes.
Hasn稚 started since. Blew out carb with air, but couldn稚 get main emulsion tube screw out with carb in place. Put bowl back on and carefully adjusted throttle cable. Still won稚 start, even with some starting fluid. Has spark, via old timing light between plug and plug wire.

Seems almost as though the valves aren稚 seating right, but requires a decent pull on the starter cord. Don稚 have a good compression gauge. Possibly carb emulsion tube is plugged? I知 stumped and am tired of trying to fix it myself.

Ralph

RalphVa · Jan 30, 2008

I gave up and took my 14SB to a good repair shop here(P&L in Ch'ville).

All they did was to firmly seat the overhead valve lifters into the cam. I apparently didn't have the ball-like end of it down against the cam in its proper position.

Starts and runs like a champ now.

Recently took my 35 year old Stihl chain saw to them, too. All they did was replace the spark plug. It starts first pull now. Had them fix a newer Craftsman chain saw that wouldn't start after hot shut down. All it needed was a new air cleaner. Had them tune up my Lawnboy, too, as it was getting to where it wouldn't start on the first pull, cold and hot. Good time of year to take stuff to them. They're not busy.

Ralph