MG MGB and MGB GT Tech Talk
Attached are photos of what happens when a bolt and washer come out of a vernier. Bolt/washer got on the outside of the chain and sliced the timing cover like a can opener and then lodged near the crank. Somewhere in there the chain broke and teeth were chewed up. No locktite on the bolt.
I hope that when yo got it rebuilt it came with a warranty on the rebuild. But sorry to hear about this disastrous accident
Yeow! Could you have safety wired those cap screws and maybe prevented this from happening? I've considered one of those gears but had bad feelings of what happened to your engine. I elected to go with the offset key method to get my timing set up.
Nothing too serious in those pictures, how about internals, did you escape without serious harm to crank, pistons, rocker, etc... or is that still under investigation? Any reputable shop would deal this problem honorably so take it up with them.
I have used the vernier cam gear on several hot street motors I have built and have never had that problem. I do however use locktite on the allen screws and use an allen wrench that is used with a torque wrench. Unlike the Kent gear I use you could drill and safty wire the ones used with your gear. If I were a betting man I would bet you have bent valves as well. Also it looks like your mechanic is using way too much selicone in his assembly.
Yep, that's the Romac Rollamaster vernier, I used them on several engines, always locktited the bolts, never had a failure. I like Tom's advice, on checking for bent valves, even though it didn't take long for the motor to shut down, all it would take is one wack to bend a valve or two, and it may only be very slightly bent at that, but I would pull the head and the valves and check them all, chances are if the valves hit the piston, damage is at a minumum there, and the pistons are ok to be still be used.
Is it just me or has there been a sudden rash of timing chain incidents?
Pete
GERONIMO Wrote: