Timing Chain skipped a tooth

[FinalImpact]

Fact is; with a loose tensioner (NO TENSIONER) it will IDLE LIKE SH$T but it may NOT be off a tooth all.

HIGH RISK, go for the Gusto repair: Pull the plugs, tighten the tensioner and turn it over by hand through the removable cap on the CKP cover. If it turns 720 degrees w/out colliding, hit the starter (Risk is bending the valves). If its still turning, throw a compression gauge on one hole. If the # is good its very likely still "in time" but the loose tensioner caused erratic operation.

LOW RISK repair: Pull the plugs, valve cover, CKP cover. Check the timing by aligning TDC on the firing stroke.

HINDSIGHT says its VERY unlikely the chain can skip over the larger intake & Exhaust gears, MUCH MORE LIKELY to skip over the crank gear with its small diameter. JMO Thus, BOTH cams are out of time. Not just one.

As we know it, there is no proof that it's actually "off a tooth". With no tension to the chain it will be hell to start, idle like crap and be ALL OVER THE MAP RPM WISE. <<Still not proof its off a tooth.

To FIX the timing if its off:
1) Remove the CCT and Loosen the guides as Marty said.
2) From other DOHC engines I've done; the chain doesn't allow the ONE gear to be removed while one remains fixed in place (Its NOT A SNAKE it won't BEND like that). HOWEVER, removing BOTH the intake and exhaust gears together allows you to orientate them correctly.

I love these threads where we discuss for weeks what to do...

 

[FinalImpact]

Thinking about it, if the chain (with a bad tensioner) can skip a tooth (a failure while the engine is running), how worn does the chain have to be as it OBVIOUSLY CAN be moved a tooth WITHOUT removing any sprockets/cams, etc? (Ship, I'm starting to talk/think like Finalimpact, )

lol

Ah yes, you're on to me now! --> Risk, likely hood, probability, consequences, Cost and how to prove it before my finger leave the keyboard! :BLAA:

See post above this one! ^^ :thumbup:

 

[TownsendsFJR1300]

The R1 has head studs,, the manual goes into great detail on the torque incriments for the head nuts on the studs.....I had just assumed that the fz6 would have head studs as well....i guess we all know what assuming gets us...:spank::BLAA:

The FZ6 manual as well, has increments too (expected for any head) to prevent warpage. ARP studs would be stonger than bolts/nuts but then your probably going to have to pull the engine as the head won't slid in but have to drop down from the top.

I suspect with the higher HP, CC's, etc, of the 1,000cc engine, the studs are extra protection.

Speaking of head bolt stretch, I find it interesting that the latest, top of the line head bolt studs (high performance), get torqued (in stages) to a certain #, THEN, they get another, say 90 degrees(for example) stretching the bolts for proper tension...

 

[TownsendsFJR1300]

Fact is; with a loose tensioner (NO TENSIONER) it will IDLE LIKE SH$T but it may NOT be off a tooth all.

HIGH RISK, go for the Gusto repair: Pull the plugs, tighten the tensioner and turn it over by hand through the removable cap on the CKP cover. If it turns 720 degrees w/out colliding, hit the starter (Risk is bending the valves). If its still turning, throw a compression gauge on one hole. If the # is good its very likely still "in time" but the loose tensioner caused erratic operation.

LOW RISK repair: Pull the plugs, valve cover, CKP cover. Check the timing by aligning TDC on the firing stroke.

HINDSIGHT says its VERY unlikely the chain can skip over the larger intake & Exhaust gears, MUCH MORE LIKELY to skip over the crank gear with its small diameter. JMO Thus, BOTH cams are out of time. Not just one.

As we know it, there is no proof that it's actually "off a tooth". With no tension to the chain it will be hell to start, idle like crap and be ALL OVER THE MAP RPM WISE. <<Still not proof its off a tooth.

To FIX the timing if its off:
1) Remove the CCT and Loosen the guides as Marty said.
2) From other DOHC engines I've done; the chain doesn't allow the ONE gear to be removed while one remains fixed in place (Its NOT A SNAKE it won't BEND like that). HOWEVER, removing BOTH the intake and exhaust gears together allows you to orientate them correctly.

I love these threads where we discuss for weeks what to do...

Makes sense, especially at the crank, where all the torque is, it would slip there.

I do have to disagree that should the marks be off, removing just one gear (or cam) for slack in the chain, to re-set everything would be fine. When I replaced the cam chain in my KLR, (4 valve overhead cam engine), I'd just remove one cam, re-set the chain accordingly and buttom it up. To pull the second cam, why, just rotate it if necessary as the chain is loose and can be moved.. If you remove the cam gear, your still going to have to rotate that cam as well to line up with the sprocket dowels.

There's really no reason to pull both cams(un-less there's damage) just to re-set the marks. As long as everything is lined up at TDC with slack in the chain strictly at the rear run (top-cam to cam taught, exhaust cam to crank taught) and the CCT taking up the slack at the rear run..

I'd be nice if the OP would update....

 

[FinalImpact]

^^ Tried to clarify that - Some chains bend enough to allow this, some don't! If it doesn't, remove both gears - takes an additional 5 min.

Point being - IF the gear is detained by the chain being bent in an unnatural way, don't PRY THE GEAR OFF! Take "both gears off".

Enough said...