So how bad is this?

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Nov 12, 2004 | 11:25 PM

SteveAngry

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So how bad is this?

<center><img src="http://pictureposter.audiworld.com/4612/michigan_turbo_006.jpg"></center><p>Hey guys.

In the beginning stages of a MC2 engine rebuild and Megasquirt EFI conversion on my 5ktq.

Anyways, I removed the head on the spare MC2 engine to do some port work and found some scoring on the cam journals.

I'm a bit concerned about this.

The scoring is really bad on #1 and light on #4 cam journals.

So just how bad of a scenario is this? Is the head still usable?

I would think so?

This head came off an engine that was supposed to have been fully rebuilt 15k miles ago so I was suprised at the scoring.

The MC2 cam that was in it is also scored.

Any Ideas, BTDT, etc?

Here's a pic of the #1 journal...

Thanks.

Steve

Nov 13, 2004 | 01:51 AM

Black-Wolf

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I would try lightly cleaning it up, and measure it...

Nov 13, 2004 | 05:34 AM

RussB

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From: Fort Lauderdale, Florida

I agree with Black-Wolf

Traditionally camshafts ran in bearings or removeable shells. About 30 years ago Japanese motorcycle manufacturers began running cams directly in aluminum heads, saving cost. Our I5 heads are the same. The downside is that when they fail in a major way, the only cure is to build up material by Heliarc welding the head and bearing caps, then align-bore the cam journals. Or junk the head.

I don't think that your cam journals evidence a major failure and in view of the alternatives, and the fact that this is a street engine, I like BlackWolf's idea.

Nov 13, 2004 | 07:17 AM

audifreakjim

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Not the end of the world,

Probably happened because the timing belt was way to tight. Like Black wolf said, clean it up a little, put a different cam in, and it should be fine.

Nov 13, 2004 | 10:25 AM

ddg=shinebox racing

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From: Los Angeles/Burbank

I had the same problem w/my "NF" head on the rear yournal....

I ended up swaping it out with another head, I still have the old one in my garage!!!!

<img src="http://pictureposter.audiworld.com/41804/imag0034.jpg">

Nov 14, 2004 | 01:42 PM

AntiSocial

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line hone

Nov 16, 2004 | 06:55 PM

Toxcheap

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I've seen this before, it usually caused by someone driving around with a bad water pump and

overheating the head badly. It's the machine shops fault instead of baking the head on a torque plate and taking the warpness out before planing they just plane it. It gives a flat surface but the cam journals suffer excessive wear. I'd just emery cloth it smooth and run it.
HTH