harmonic balancer came off crank shaft help?

[wishiknewmore]

Harmonic balancer came off crank shaft and the key slot was messed up.
put a new one on with new woodruff key and the same thing happened again.

Was having overheating and timing issues before it all fell off.
it's a 1988 MKIII turbo. So 7m-gte.
What should i do or where should i start?

[cre]

Generally, once the keyway gets chewed up most people (and a lot of machinists) will tell you the crank is trash. It can often be welded and a new keyway cut but it's debatable whether it's worth it... that's all up to you.

It's definitely not one of those things where you can just replace the key and maybe squeeze in a little JB Weld.


Can't comment on the overheating, not enough information.

[zepol_wube]

5MGE 1984 Celica Supra

I have the harmonic balancer and the timing belt gear off. Getting the timing gear off was a bear as the harmonic balancer woodruff key would not come out and the timing gear was rotated relative to the key.

Question

1. Should there be a key in the crank for the timing gear? There is none.
2. Is this a clearance engine wrt the pistons and valves?
3. If no key for the timing gear then the massive bolt torque is what hold the timing gear from spinning?

Statement

A region on the crankshaft 180 degrees from the balancer key about the size of a dime under the timing gear shows what I would call galling (weld and release transfer of material with the timing gear). Was this the key?

Engine ran fine in the morning, started fine in the afternoon, but had no power until warmed up. Got home fine and shut down fine. I checked the timing and found it was off 2 teeth. Belt checks fine, eventually found the slipped timing gear.

MAIN QUESTION HERE, was the timing gear keyed to the crank?

[interested!]

Hi! had the very same problem and fixed it cheaply,
FIRST, get the car on ramps at the front , strip to gain acess to timing belt and crank gear and remove. next ( in short ) measure and reduce crank to parallel to smallest diameter -its gone conical .I made a machined tube to min dia with a sliding pin in crank thread to maintain parallelism -using fit/mark/file--fit/mark/file --fit/mark/file -mark made by twisting to leave high spot mark -took a few days to reach the gear-. repair keyway with two part metal epoxy to refit key . THEN : machine out balancer to fit sleeve( very light drive fit ) c/w slot for key ( only make slot to cover fit depth!!!!--this must be a sliding fit on crank (only do this when you know the exact OD of the crank ). fit balancer c/w new key to crank, finally I drilled through crank/sleeve/balancer and fitted a bolt( head and thread removed ) to maintain anti spin ( its all been reclaimed ), I refitted mine with loctite when I was happy with the fit. check timing mark with piston tdc using a dti on piston crown and reassemble using new crank seal and new timing belt etc. .WELL worth the effort , repaired mine 10 years ago and still going strong -easily removeable for new belt change 8 years later.