Forgive me if this seems like a silly question, or if it has been addressed in the past. I found nothing in the Body of Knowledge, and nothing with a search. Google searches, wandering about Youtube, and searching my small library, some books going back nearly 100 years, hasn't answered this question adequately.

Due to rusted out freeze plugs (which resulted in water pouring into the oil), low compression on six cylinders, and No compression on one, pulling the heads and finding that a previous owner repaired the rear freeze plugs with JB Weld, and there are two more freeze plugs on the back of the motor, I've decided to pull the engine and replace all the freeze plugs, rings, bearings, lap the valves, and so forth.

Now to why I'm writing all this. When I pulled the camshaft on the first head, I found that a couple of the camshaft bores were a little less than perfectly smooth. I can just feel a little roughness, barely noticable. I've included a photo. This is the bore next to the timing chain sprocket.

When I was a kid, 40+ years ago, when I could take a pair of heads to a machine shop and they'd refurbish them for $25 plus parts (usually they'd find a valve or two). If it was still that price range (about $160, adjusted for inflation) there'd be no question...I'd just turn them in. But the last time I had a head worked on (for a three cylinder Geo Metro) it was $300 plus parts. So how much damage to the bore surface is acceptable? Camshaft journals are within spec, if what is shown in the photo is acceptable, then I'll get some plastigauge and verify the bore diameter. Thank you in advance.


Edited by Joebob (09/08/20 09:34 PM)