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Few weeks ago just completed engine overhaul and installed it back to my EK.
(gsr block + 81.5 ITR pistons, B16B cams)
GSR Head was milled 0.04mm, valve and seats were cutted, exhaust valve guides were changed; ti retainers and spring type LMAs.
Also I installed B16B type-r cams. I know previous owners quite well and they didn't has any problem with cams in gsr heads.
After few hundred miles of break in I opened the valve cover to adjust valves and realized there scratches/gouges on all intake low cam lobes. The scratches mostly on the closing side of the lobe and only on a intake valve. It is not deep, but I feel it with a nail (not all of them).
Rocker arms were assembled in the same order as it was originally there, assembly lube was used.
Also checked the old cams and there is same kind of scratch pattern, but I can't feel it so that is only a cosmetic damage. Rocker arms looked really good before cams were installed.
Only thing I could see is a piece of trash/metal getting caught between the cam lobe and rocker and damaging the rocker pad. Once the damage was in the pad, it transferred it to the lobe. (or vice versa).
Once the new cams were put in, the scarred rocker pad transferred to the new cam.
Any chance something coulda got in when the valve cover was off last time?
It would have to be something pretty hard to scratch the cam like that. I doubt that's what happened. what do the rockers look like when the rockers were removed the shafts, plugs, and orifaces were installed correctly? This looks like and oiling issue. What lmas did you use? How stiff did they feel? I've seen people install the rockers incorrectly and the center rocker not go all the way down and the vtec pin kinda lodge at an angle. It damaged the rockers and cams pretty bad looked similar but worse than what you have
It would have to be something pretty hard to scratch the cam like that. I doubt that's what happened. what do the rockers look like when the rockers were removed the shafts, plugs, and orifaces were installed correctly? This looks like and oiling issue. What lmas did you use? How stiff did they feel? I've seen people install the rockers incorrectly and the center rocker not go all the way down and the vtec pin kinda lodge at an angle. It damaged the rockers and cams pretty bad looked similar but worse than what you have
Wouldn't an oiling issue cause more of an even wipe across the lobe? It looks like there are deep grooves cut into the lobe(beneath the surface) to me. I would think insufficient lubrication would wear It down more even no?
Actually looking at it closer, I think it might be an oiling issue as well. How's oil pressure?
Looks like an oil supply issue to me or at least definitely metal to metal contact from wiping. Cams are wiped to the point that galling took place and would be scratches on the closing side. That is where the scratches came from if you look at the start and stop points. Most likely rocker pads have been comprised.
You need to pull all the caps and verify the feed port to the rail isn't clogged and that the rail itself isn't plugged. People tend to overlook cleaning those parts when assembling and engine. I personally spray brake cleaner with the straw through them to verify consistent flow (gauging by eye of course ). Also verify the o-ring and dowel are not damaged or missing.
08-10-2015, 07:57 AM
B18 Intake Camshaft scratches
). Also verify the o-ring and dowel are not damaged or missing.
