Help! I think I just made a very costly error...

[GreatOldOne]

Guys,

I've just started dismantling the engine. Head came of fine, everything was going hunky dory until I tried to turn the crank to see what the cylinder bores where like - forgetting that I'd left the fly wheel bolts in the back so I wouldn't loose them.

Well, one of the bolts caught on the engine stand, bent and popped the side out of the mounting flange:



There wasn't that much resistance, which was funny... I can only guess that the was a crack or a flaw already there and I just made it worse.

What I need to know is just how bad this is. I can't see if this flange is an integral part of the crank, or if it's a part than can be replaced on it's own. I have a funny feeling (well, more a feeling of dread) that it's going to be former, which I would assume means a new crank - Ouch...

If this is the case, the next question is (and this may sound insane), but could I use some JB Weld on it? According to the packaging, it'll withstand 4,000 1b/in. of pressure:





Thanks in advance,

Jason (GOO)

[GreatOldOne]

The more I look at this, the more I think I may get away with it - here's why:

The threaded portion of the flange seems to be intact (I can thread a bolt in there no problem, all the way through) - the bolt seems to have only been in half a turn or so, and has popped the non threaded portion - so when I torque down the bolt in there, all of the pressure will be going into solid flange, not a join.

[MartinClan]

If that were me I would get another crankshaft. I guess you could get one from the E30 zone for £not very much. Several reasons

1. Peace of mind
2. The forces on those bolts when the crankshaft is rotating at 6000 rpm must be huge
3. Flywheel exiting through bell housing and footwell not good!
4. Crankshaft and flywheel are balanced to a very fine tollerance.

All IMHO of course

Robin

[Patrick]

Personally I would replace it as Robin's said its not very expensive getting parts on E30Zone. It's one of those things that will probably hold for a while but eventually it may break off.

[GreatOldOne]

Yeah, having slept on it, it'd madness not to replace it. You now what it's like - you've just fudged something up big time, and you start casting around for quick fixes...

Ah well. Guess this means a complete rebuild now...

[GreatOldOne]

How much is a reasonable price for a 2nd hand crank? I've just been offered one for £70 inclusive of delivery for a guy on e30zone...