OldGray320i GRM+ Memberand Dork
2/9/20 5:35 p.m.

I was changing the timing belt oon the Miata,  using the two crescent wrench method to hold the cams. 

Exhaust cam torqued to 40 ft lbs just fine, but the intake cam had a e36 m3ty wrench and it moved. 

Go to pull the thing off, and as I wiggled back and forth,  I chingered the lobe a bit.  It's got a bit of an edge to it. 

How effed am I?

GameboyRMH GRM+ Memberand MegaDork
2/9/20 6:14 p.m.

Not very. You could polish the damage smooth (as in no sharp edges and no protrusions above the original surface - tape off the undamaged areas so you don't take material off them by accident) and the engine will run fine with slightly reduced life on that lobe/lifter. If it were a modified valvetrain with higher pressures at the cam/lifter interface, it'd be worse.

BoxheadTim GRM+ Memberand MegaDork
2/9/20 6:18 p.m.

I'd use something like a sharpening/grinding stone to carefully try to smooth it out. As GameboyRMH mentioned, it's probably shortened the life of the cam and lifter a bit, but I'd just keep an eye on it if it doesn't have any sharp edges.

Good news is that a good used stock cam shouldn't exactly cost a lot of money.

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