Cylinder decking done…. But not sure about the results

[JZ05220r]

I had a 220 cylinder repaired, and replated. There is a ridge at the end of the mating surface that I can feel with my finger. It seems as though there wasn’t a complete follow through with the milling machine. I think this could possibly affect the head gasket sealing good. Here’s a picture of it. The darkness isn’t a shadow. but it’s definitely sticking up in that area. Thoughts? Thanks

[SS109]

Yeah, that looks like it might cause a problem. You could probably knock it down with some fine emery cloth and a hard backer and it would be good to go.

[JZ05220r]

Yeah, that looks like it might cause a problem. You could probably knock it down with some fine emery cloth and a hard backer and it would be good to go.

Ok. I still need to have my exhaust port repaired because of the pipe leaving deep markings in it. I may just have them look at and correct the high spot as well. Thanks

[SS109]

Yeah, that looks like it might cause a problem. You could probably knock it down with some fine emery cloth and a hard backer and it would be good to go.

Ok. I still need to have my exhaust port repaired because of the pipe leaving deep markings in it. I may just have them look at and correct the high spot as well. Thanks

Yes, that would be the best. I assumed you had shipped it out so it would be a hassle to get them to fix it.

[KDXGarage]

blue machinist spray?

[JZ05220r]

blue machinist spray?

I know I have some layout fluid somewhere but I couldn’t find it.

[KDXGarage]

If it was mine, I would get a piece of glass, a sheet of paper and that blue stuff. Maybe that would show how bad it was.

[pumpguy]

Checking for flatness using plate glass or similar surface plate and marking medium like Prussian Blue will only confirm the high spot. You still need to remove it so the whole joint face is truly flat and parallel.

Removing the high spot requires careful work with a scraper and long fine flat file. This is a cut and try process until the whole joint face is truly flat.

IIWM, I would just carefully work on it with a long flat fine file. Its not really all that difficult.

[Chuck78]

I have a scrap slab of decorative stone that's milled perfectly flat and highly polished. Wall panels from a 120yr old building that I repurposed as countertops. Checked with feeler gauges and a Machinist's straightedge, it is dead flat... I use this as my "suface plate" with a fresh can (CLEAN NOZZLE!) of 3M adhesive and 220 grit floor sander sheets, and WD40 as lubricant, and I confidently clean up head gasket surfaces on twins, 4 cylinders, and single cylinder engines with it.
I was a huge skeptic of the guys using tempered glass or thick MDF sheets as a similar surface plate, but the results I've achieved with my setup speak for themselves, it's pretty phenomenal.
Taking any significant thickness off though, that'd take FOREVER... these are just for cleanup passes.

I'd recommend James on yours, if DIY repairing that, to try and clean it up close to flat with a fine toothed file first, before flipping it upside down on any sort of makeshift surface plate / abrasive sheet setup.
that last step isn't even really needed, as this is not really a sealing area, but does need to allow it to be torqued down evenly with no high or low spots - that would cause distortion and warpage.
Otherwise you'll take too much off the opposite side and end up with a slanted deck if you just start out on a surface plate sanding sheet.
Ideally it'd be best to check it with Machinist's blue dye marking compound, and have the shop finish the resurfacing job they started.

[JZ05220r]

Thanks guys for the suggestion. I’ll get it sorted out one way or the other.

[KDXGarage]

Was it dropped??

[JZ05220r]

I don’t think so. At least not by me

[John_S]

Did you call Millenium or whoever did the work for you? Even though it sucks to wait for it, I would've had it back in the mail the following day. I wouldn't try to complete the work myself for something I just paid to have professionally machined.