Mysterious spring found in head & LS crank case
Posted: Fri Mar 18, 2022 1:08 pm
I can use some help identify where in the world this spring could be from. Photos attached. Details in order below.
-Top end rebuilt 1 year ago with new KW valve kit. Also new carb. kit. Rode track once, desert twice. Ran great. Kept fluids moving by riding neighborhood canals 1x a week.
- Worked great on last ride out. Would not kick over 8 days later.
- Removed and cleaned carb. Carb appeared in good.
- Checked valves and timing. Timing off one tooth. valves to spec, no warping. We discovered (left-side) shim missing and worn exhaust valve retainer (left-side). Also found a random spring (tiny fragment) sitting on valve holder (see pictures). Shim was in the head with no damage to shim.
download/file.php?mode=view&id=1129
download/file.php?mode=view&id=1128
-Cleaned head. Purchased new KW valve retainer ($36
), re-assembled and would not kick over still.
- Dissembled, removed valves and found one more "chewed up" spring piece in head. We suspected the spring piece had to have come up the cam chain. So I fully removed cam chain tensioner and discovered a broken tensioner (pictured). Did not suspect spring cam from tensioner, spring is too small. Suspected something in the gears but couldn't find anything in the manual/parts diagrams of that size.
download/file.php?mode=view&id=1127
- Drained oil and filter to find shavings in filter (pictured). Removed Crank case and discovered many more pieces of small said spring. Talked with a few mechanics and no one could recall a spring of that size natively in this engine.
Please take a look and see if this spring looks familiar. I'll be splitting the case for further inspection this next week.
-Top end rebuilt 1 year ago with new KW valve kit. Also new carb. kit. Rode track once, desert twice. Ran great. Kept fluids moving by riding neighborhood canals 1x a week.
- Worked great on last ride out. Would not kick over 8 days later.
- Removed and cleaned carb. Carb appeared in good.
- Checked valves and timing. Timing off one tooth. valves to spec, no warping. We discovered (left-side) shim missing and worn exhaust valve retainer (left-side). Also found a random spring (tiny fragment) sitting on valve holder (see pictures). Shim was in the head with no damage to shim.
download/file.php?mode=view&id=1129
download/file.php?mode=view&id=1128
-Cleaned head. Purchased new KW valve retainer ($36
), re-assembled and would not kick over still.- Dissembled, removed valves and found one more "chewed up" spring piece in head. We suspected the spring piece had to have come up the cam chain. So I fully removed cam chain tensioner and discovered a broken tensioner (pictured). Did not suspect spring cam from tensioner, spring is too small. Suspected something in the gears but couldn't find anything in the manual/parts diagrams of that size.
download/file.php?mode=view&id=1127
- Drained oil and filter to find shavings in filter (pictured). Removed Crank case and discovered many more pieces of small said spring. Talked with a few mechanics and no one could recall a spring of that size natively in this engine.
Please take a look and see if this spring looks familiar. I'll be splitting the case for further inspection this next week.