Killerwhale wrote:DOBBO wrote:I think once the cam cover is off, set your cam timing marks up. Remove cam tensioner and from memory you have to remove the cam sprockets because the chain fouls the side of the camchain tunnel with the sprockets in place. Be sure to tie a piece of wire to the camchain so you can retreive it when the head goes back on.
So cam tensioner has to go? Good because not mentioned on swedish forum or in Haynes!!
Then Haynes is a load of sh*t, download the Yamaha workshop manual, it also has some annoying things missing, but I reckon combining both will give You a better picture. It at least tells You how to position the crank and piston, and how the cams shuld be positioned. And since You have slotted sprockets, mark the shaft/sprockets properly before loosening the bolts. And be careful, if You loose a bolt, nut or washer into the engine while having the head off, it will be a pain to find it...
From the top of my head these steps are required, in case Haynes/Yamah is missing something (but the chance is I forget something instead...).
-Coolant out
-Fairing off (optional, I normally don't)
-Radiator off (tight fit when the fairing still is on)
-Carbs off
-Headers off (can be a bitch)
-Water pipe to the valve cover (One tiny allen bolt deep down)
-Valve cover off
-2 small peek covers on the LH side of the engine (generator cover, for checking crank position and rotating crank)
-Cam tensioner (put it in least tensioned position while You're at it then U won't forget it later)
-Rotate crank until You see the 'T' positoned to the mark on the generator cover
-Check Your cam positions (mostly out of interest and to see how it should be positioned later), there are markings on the cams that should be in line with markings on the cam "överfall", don't know the English term...), bitch to see without a small mirror. There are also markings on the sprockets the should be lined up with the side of the head. Don't be afraid if they aren't exactly lined up, Your workshop changed the timing slightly, they should at least not be one tooth wrong when re-assembling.
-There's a small steel plate covering the sprockets/chain (these bolts should not be tightened harder than 10 Nm when assembling)
-Loosen the inlet sprocket bolts (and don't drop them!)
-Pull the sprocket/chain of the cam
-Tie something to the chain
-Pull out the forward black chain-follower (just pull it upwards)
-Loosen the headbolts (this is where the special prolonged allen socket is handy.) There are two smaller bolts where the chain runs, easy to forget
-Wiggle the head carefully upwards, with the chain tied up.
-Take out annoying sparkplug part
-(Overcourse, but checking valve play is much easier with the head off, but I reckon the workshop did this for You already)
-Put head back, and try to have the chain positioned so it's not getting between the head and cylinder
-Make sure the crank hasn't moved out of position
-Position the exhaust cam correctly, tighten up the slack in the chain, and put the chain/sprocket back in the right position (Might be tricky if the valves are partly opened. It's not dangerous to rotate the crank plus the cams a bit, as long as everything is moving the same amount. Just make sure You rotate it back to the marking positions, and check the markings.
Once You have tightened the sprocket back in the right position, and the chain/cams are aligned, rotate the crank by hand at least one full turn. It should be possible to rotate it without too much power (although the valves will open and this will make it harder to turn the crank in certain positions). Check all the markings again, then just put it all together.
-Tighten the head bolts with a torque wrench...
-Before starting, I'd suggest merely as a precaution (better to be safe than sorry), that Yo leave the plugs out, and crank the engine over with the starter. No loud noises from the engine, and You're hopefully fine
. I would also for safety check the oil pressure with the small bolt on the LH side of the head out. Once You have oil coming out from there You're safe. Probably not necessary, but again, safe is better...
-Put some aluminium paste (Biltema
) on the whole length of the exhaust bolts, that makes life so much easier the next time...
Good luck!
