It didnt change your rod and main clearances cause they shave the surface of the caps that fit against the block to make the caps smaller. That gets them back into spec.
Damaged Cams on 7m-gte?
- Thread starter GotBoost?
- Start date
Just so you know. Like I mention before, my cams looked pretty rough so I had them polished. I was kinda concerned about the clearances after that, as they looked like to polish them like they are now, that alot of material would have had to be taken off of them. So I found the specs in the TSRM today, and micd them out and everything is still within specs. Some of the cam journals were pretty close to the minimum measurements, but all the lobes and journals are good. I will also plastiguage them to double check.
Hey everybody. Thanks for all the input. My camera had gone missing for a couple weeks, but I finally have pics here. I did notice that the very light scoring is limited to journals 1 and 2 on both cams. I'm sure the head had some warping, as the stock headbolts (which previous owner had reused! :icon_mad: ) were only finger tight when I removed the head. Back to the scoring. It's light enough that my fingernail won't catch at all, but you can feel it with the tip of your finger. The journal material is so soft, that even the lightest touch of my fingernail is enough to leave marks on the journals (the marks go away if I rub them with my thumb).
I hope you guys can make sense of my rambling. I'm sure polishing would be enough to erase the scoring. I'm thinking of ways to polish them, and mic the journals before and after ( I do have a tsrm). After all, my machinist says the cams are ruined (he didn't provide me with journal measurements). So what do you think of the pics? Hopefully you can see anything. The pic of only one cam tries to show you one smooth journal, as comparison. Thank you all
I hope you guys can make sense of my rambling. I'm sure polishing would be enough to erase the scoring. I'm thinking of ways to polish them, and mic the journals before and after ( I do have a tsrm). After all, my machinist says the cams are ruined (he didn't provide me with journal measurements). So what do you think of the pics? Hopefully you can see anything. The pic of only one cam tries to show you one smooth journal, as comparison. Thank you all
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90 percent of all the 7m cam journals i,ve seen look like that ....you can clean it off yourself with a piece of grey scotchbrite in minutes .
Its nothing to worry about .
The main area of concern is the condition of the cam journals in the cylinder head/caps which will invariably have some scoring .
Its nothing to worry about .
The main area of concern is the condition of the cam journals in the cylinder head/caps which will invariably have some scoring .
Dr Evil said:
Thank you all. The machinist and I checked the inside of the cylinder caps, and they're all smooth as can be. Only the cam journals got this slight scoring. The problem is, the machinist says he wants new cams, or he won't guarantee his work on the head. I'm thinking i should polish and mic the cam journals, and maybe then he won't insist on new cam$. eh
my cams, looked like yours, but i did not want to reuse them, so i went to a junk yard, I got some of an n/a.
If he doesnt offer cam polishing as a service then find a machine shop that has a crank polisher and have them do it. Then take your machinist the cams and have him mic and plastiguage or just plastiguage and that should offer proof positive whether they are in spec or not. Also $1200 sound outrageous for head work. I had mine resurfaced, pressure tested, and a 3 angle valve job and he installed new oil seals for $275.
both head i had done (fully done) costed 850+taxes
that is disassemble + reassemble labor
valve grind
cleaning
straightening in an oven on a flat plate
resurfacing
cheking line bores
polishing cams
helicoils, threads & studs all checked
cleaning and bead blast ports
24 new valve guides
shims to spec
Obviously not in order and could have missed things.. but this is what i expect done to a head when it is fully remanufactured. Tho it is not necessary to have all 24 valve guides changed they do it any way.
The main thing to note is that the head was straightened first in an oven then it was resurfaced. If you skip straightening the head you could have a permanently bananna shaped head that will bind the cams after you surface it.
that is disassemble + reassemble labor
valve grind
cleaning
straightening in an oven on a flat plate
resurfacing
cheking line bores
polishing cams
helicoils, threads & studs all checked
cleaning and bead blast ports
24 new valve guides
shims to spec
Obviously not in order and could have missed things.. but this is what i expect done to a head when it is fully remanufactured. Tho it is not necessary to have all 24 valve guides changed they do it any way.
The main thing to note is that the head was straightened first in an oven then it was resurfaced. If you skip straightening the head you could have a permanently bananna shaped head that will bind the cams after you surface it.