MY RANCHER HAS BEEN TAPPING FOR A WHILE, THIS PAST WEEKEND IT STARTED SMOKING REAL BAD, SO I PULLED THE HEAD CHANGED THE RINGS AND SET THE VALVES, BUT IT IS STILL TAPPING BAD, I WAS TOLD I NEED TO REPLACE MY CAM CHAIN AND CAM CHAIN FOLLOWER, IS THIS POSSIBLY THE PROBLEM ANY SUGGESTIONS????

 

If the cam chain is stretched, then yes it could be the problem. A stretched chain could be prone to popping off at any moment as well. With a stretched timing chain you'll get incorrect valve timing and the valves could be slapping the piston since they are opening at the wrong time(s). It is definetely worth replacing if you have taken care of the rings and valve adjustments already. Also inspect the cam to make sure it is not showing excessive wear.

 

Replace the rockers, rocker pivot shaft and holder assembly.
At least pull the tappet cover, remove the rocker holder assembly. Remove the set bolt and slide the rocker shaft from the holder. Check it for wear in the rocker pivot area. Also check the inside of the rocker arm pivots for egg shaping. It is most likely where the tapping is coming from. When you adjust the valves with worn rocker shafts, the clearance is correct, it pushes the bottom of the rocker pivot up into the worn spot on the shaft. Then as much as it pushes up, it leaves a gap between the rocker and shaft on the top side of the shaft. That is where I believe your tapping noise is coming from. Seen it hundereds of times before.
Word of warning on the cam chain (Probably not the issue I am sure), the cam must be pulled out a little to spool up the chain (cocked to the side). Here is what can happen. When the cam is pulled outward from the case, many times the cam pulls out leaving the inner cam bearing in the case. Between the cam bearing and decompressor there is a shim washer. The washer normally will fall inside the engine. If you are not aware of the washer dropping it can cause serious issues internally.

----- Gimpster -----

 

SO I SHOULD CHANGE THE ROCKER ARMS,PIVOT SHAFT AND HOLDER ASSEMBLY BEFORE MESSING WITH THE CAM CHAIN THAT SEEMS ALOT EASIER ?? I HAVE ALL THE PARTS ON ORDER SO I'LL JUST RETURN WHAT I DONT USE. HOPEFULLY THIS WORKS I CANT WAIT 8 WEEKS ON OUR LOCAL DEALERS TO FIX IT.

 

WOW...8 weeks !
Yes, the majority of Ranchers I have serviced rattle noises on have been the top end, in the rocker area. Older footshift Ranchers do not have a fan on the oil cooler and this takes its toll on the top end under prolonged heavy use. On some the piston skirts become scored from being so hot that the piston will make a tapping noise. Real bad is when the heat causes the cylinder studs to pull out of th eengine case. The two studs holding the rocker holder down are the most common for doing this. The cam chain in this engine platform is short, as it is a pushrod engine so the cam is in the bottom end right next to the crankshaft in the bottom end. It is possable for a chain in them to 'kink', not as likely as a chain in the overhead cam engines. I have seen some chain tentioners fail over the years in the rancher, not a lot though.
Of coarse the best way to determine where the noise is coming from is with a stethescope. Listening at the tappet cover, side of the head, front engine cover, rear cover and top of the engine case around the cylinder. I say front engine cover because there is a bearing in the front cover where it slips over the crankshaft. I have seen these bearings go bad also and make a ticking sound.
Hope you have good luck getting rid of the noise.

----- Gimpster -----

 

From my experience the noise you are hearing is probably the upper rod bearing clearance to the piston wrist pin. The timing chain on the Rancher is too short to give a noticable ticking sound - and you have to pull the engine to get to it since it is on the back end of the engine.

We've done hundreds of 350 Rancher engines in my dad's ATV shop since they came out in 2000, and I can't remember any time we've had to replace the rocker assembly - it's always been in the crank/rod assembly - $140 from Honda, Of course the wear is on the wrist pin too, so a new piston kit would be advisable.

 

I BOUGHT A MECHANIC stethescope AND THE NOISE IS COMING FROM THE VALVE AREA? IM GOING TO CHANGE THE ROCKERS, PUSH RODS, AND ROCKER ASSEMBLY SINCE THESE PARTS ARE COMING OVERNIGHT TODAY HOPEFULLY IT WILL WORK>

 

OK SO I HAVE CHANGED THE COMPLETE ROCKER ASSEMBLY, PUSH RODS AND READJUSTED THE VALVES AND I STILL HAVE THE LOUD TAPPING NOISE. I HAVENT TORN THE VALVES DOWN PUT THEY DIDNT LEAK WHEN I DID THE SOLVENT TEST. COULD I HAVE A BENT VALVE, BUT THE NOISE SOUNDS LIKE IT COMING FROM THE CYLINDER. MAYBE I NEED TO COMPLETELY TEAR DOWN AND REBUILD THE ENGINE. ANY OTHER SUGGEGSTION BEFORE I PULL THE ENGINE, I HAVE $500.00 STUCK IN THE ENGINE AND STILL NO LUCK. THANKS FOR ALL THE HELP SO FAR

JASON

 

Crankshaft/Rod assembly - Gasket set is available aftermarket, the only gaskets are the cylinder base, head, exhaust, and valve cover - all the rest is silicone. Piston kit is available aftermarket - we've had real good results with the Namura brand moly coated pistons. Might as well drop a new timing chain in while you have it apart. The service manual is available on the internet, the engines are the same if you can't find a service manual for your specific year, the only differences between the years is how the electronics work - the mechanical part is still the same. You can purchase a manual at freebrd.com

The only special tool needed is the flywheel puller - if you don't have access, you can carry the engine bottom end to your local shop and they should pop the flywheel off for you. Clean everything very good while it is apart - the "sludge" has grit stored up in it and could possibly eat your new rings up quickly if you don't clean everything.

 

I FINALLY HAD ENOUGH, SO I BROUGHT IT IN TO HONDA TOLD THEM I WANT IT FIXED SO I COULD TRADE IT IN,THEY PLAN ON HAVING IT FIXED TUESDAY THEY THINK IT IS PISTON SLAP AMAZING HOW FAST THEY DO SOMETHING WHEN THEY CAN MAKE EXTRA MONEY. DOES ANY KNOW WHAT A COMPLETE ENGINE REBUIL COST AND WHAT IS THE BIKE WORTH FOR A TRADE IN?

THANKS, JASON