Scratches inside cylinder head

[RustyTank]

Hello all. I've got the top end of my 1979 GS850 apart right now. I noticed yesterday that just above where #2 intake valve and springs sits there's some scratches in the cylinder head casing. I didn't really know what to think about it, other than, someone else, at some point, has taken this top end apart. The PO is a friend of mine and he says he hadn't opened up the engine at all, so had to be someone prior to him. I don't think this had any negative impact on how the bike ran, but I wanted to see what you all had to say about it.

 

[mehall2]

From your picture, I would guess that someone along the line may have attempted to remove a shim without the correct tool.

 

[GregT]

From your picture, I would guess that someone along the line may have attempted to remove a shim without the correct tool.

Or had a valve spring compressor slip.

 

[Maddevill]

Just smooth down the raised metal. Hopefully the valve guide is in good shape.

Mad

 

[2BRacing]

I would be more worried about that cam journal surface.

 

[bwringer]

From your picture, I would guess that someone along the line may have attempted to remove a shim without the correct tool.

Something like that, yeah. I'm having trouble picturing exactly what they were trying to do, but the mind of the PO is a terrible, strange place I do not understand. But that sure looks like human error. Maybe some weird accident with a homemade valve spring compressor. Maybe they shattered a shim trying to get it out with a screwdriver or something, and a piece bounced around in there.

I would be more worried about that cam journal surface.

Same. Are the other journals OK? What does the cap on that journal look like? What does that surface on the camshaft look like?

The damage around the valve bucket well is pretty much irrelevant.

 

[1980GS1000E]

If the cam journal shown checks out as far as wear, except for that damage, and the cap is ok, then that would work fine. Check the clearance.

 

[RustyTank]

Just smooth down the raised metal. Hopefully the valve guide is in good shape.

Mad

Yeah, the guide seems to be in good shape.

 

[RustyTank]

Are the other journals OK? What does the cap on that journal look like? What does that surface on the camshaft look like?

The damage around the valve bucket well is pretty much irrelevant.

Here's pics of each journal, and the cap in question. They all look fine to me but you guys would know better.

 

[RustyTank]

If the cam journal shown checks out as far as wear, except for that damage, and the cap is ok, then that would work fine. Check the clearance.

Thank you 1980GS1000E. The engine ran pretty well prior to disassembling, so I'm under the impression the scratches were of no significance but, of course, I wanted to get a consensus from the group.

 

[Maddevill]

Oofah. Some scoring on the cam journals. If you can feel the scratches with a fingernail, you have problems. If you can't, just buff them a little by hand with a Scotchbrite pad.

Mad

 

[RustyTank]

Oofah. Some scoring on the cam journals. If you can feel the scratches with a fingernail, you have problems.

Thanks Mad. Just went over all of the journals with a fingernail, smooth as a babies bottom. It's my understanding that there's gonna be some scoring, and that this amount is completely normal.

If you can't, just buff them a little by hand with a Scotchbrite pad.

With respect, wouldn't a Scotch-Brite pad scratch up the surface?

 

[RustyTank]

What does that surface on the camshaft look like?

I checked out the camshaft, it looked fine, no dings or obvious scratches.