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jsmiller, it would help if we knew if the peck (noise) you were hearing was once per rev or every other revolution? That alone can eliminate some things & highlight others.. -Lets start with the valve train.. I presume you used a feeler gauge to set the valve lash? On an older valve train that can leave excess clearance due to step wear on the rocker arms & loose rocker arms on the rocker shaft.. The first thing to do is buy, find, or make some thin shim washers that will fit the rocker shaft.. Then shim most of the rocker arm side play out of the rocker arms.. You don�t want them tight but just get them down to have very little side play.. Try to keep them centered over the valves also. -Then to adjust the valve lash take your feeler gauge & toss it back in your tool box.. Make sure the valve being adjusted is closed & on the low place on the cam lobe,, then tighten the valve adjuster slowly until the push rod just becomes snug & the fore/aft movement just goes away,, then back the adjuster off 1/3 turn (that�s 2 nut flats if the nut moves with the adjuster).. That should leave your valve right close to .020� accounting for all the wear.. Using a feeler gauge on an older 2-cylinder usually leaves the valve lash too loose. The adjustment should also be made on a hot tractor (not just idle a while hot but a working hot engine).. Using a feeler gauge or adjusting them on a not working hot engine usually leaves them a little on the loose side. That leaves them noisy but on the other hand but loose valves are good for durability.. -I presume you got ALL the top ridge out when you had the cylinders machined? If there is much of a ridge left you could have a ring hitting that ridge. -I suppose you could have a piston slap condition but those pistons usually just lay on the bottom of the cylinder bore & don�t make any noise until a load is applied so if the noise is at idle without a load that probably isn�t your problem.. -If you didn�t have the crankshaft turned you could have a loose rod bearing. Those crankshafts usually wear the rod journals egg shaped so even with the bearing clearance set you could have a loose spot just as it fires [worst wear place]. -OK, now on the wrist pins? YES, those could be loose & can be a problem area if worn or improperly honed when installed.. Probably the best approach there is to pull the crankcase cover, then pull the spark plug wires (for safety), then reach in & place your hand (or wedge a couple of fingers) between each piston & connecting rod top,, then rock the flywheel back & forth.. Any looseness or movement felt between the rod top & piston means loose wrist pins.. -Another place I have found noise on a those old 2-cylinders is crankshaft gear to governor gear play.. That is usually more pronounced at low idle or just as the engine rolls to a stop at shut down.. -There�s lots of other places an engine noise can emanate from like a crank throw hitting an oil line, a bent push rod hitting a tube or block passage, loose side clearance of the piston rings in a ring groove, flywheel spacer hitting the housing, excess crankshaft side play.. If the noise is more loose log sounding even a main bearing problem.. ~Onto your fan gear whine problem.. You say..
Quote: --�I know that it needs matched governor/fanshaft Gears But I have a ton in it now!! The matched Gears whine and are a little loose. -Those fan gears do tend to whine some if not reassembled back exactly to the same adjustment & heel setting as they were run at before.. They will usually quiet down in time though. -The number one thing I usually find on those used fan gears making noise or even self destructing is not removing the gear teeth side flashing & worn tooth burrs before reassembling.. You need to take a stone or very fine file & remove all the tooth sharp flashing from the gear teeth.. That flashing usually shows up just outside the original worn in spots.. Another thing I find is setting-up used gears up too tight.. Those gears don�t wear evenly due to the harsh firing of the 2-cylinder engine so will run tighter in some tooth contact areas than other.. I never set a used set of gears up too tight & tend to set to the upper clearance range (at the tightest point in the gear rotation).. If the gear wear contact pattern shows those gears were run with a poor heel setting I tend to bias my setting towards the original contact alignment.. I have re-used many well run in fan gears in my life & as long as the teeth are honed free of any flashing & sharp edges & the teeth aren�t worm to a sharp point, & they aren�t set up too tight they usually quiet down after some run in time & don�t cause a problem.. -One last thing.. If you don�t have one, you might want to visit your local auto parts store or discount tool center & buy a mechanics stethoscope.. Those things are a real help in locating engine noises.. -If you want to do a little digging- try running that engine until hot (or the noise starts) then short one then other spark plug to ground & see if your noise changes,,,,, ,, Then try shorting the generator�s (F) post to a nice clean ground (usually need the engine running faster for this), that will place a high generator load on the governor gears, fan shaft & fan gears.. If that changes the noise to be less, your problem is probably from the governor up. -Try towing the tractor in gear with a quiet running vehicle.. If the noise changes your noise is probably firing related.. -Make sure the fan clutch is working & not all frozen up.. -Try different ignition timing settings as that can change an engine noise & help with diagnostics. If you can do some of the above & then post back with any changes or differences, or even add to our knowledge of when the noise happens, differences hot / cold, under load, driving the tractor, etc.. we can then make a more informed estimation.. Engine noises are hard enough to diagnose while working on the tractor let alone over the internet so the more feed back you can supply the closer we can get� Happy noise hunting�.
Clooney
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