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1G Cam cap scratch questions

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enriquez2000

Proven Member
2,269
810
Oct 5, 2014
fort collins, Colorado
I started taki g my head apart while motor is headed to the machine shop.

I inspected my cam caps and they have scoring... my question is how much is normal?

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That's a bit more than I'd personally like to see. Clean it up lightly oil the journals and cam and put the end caps on, see how it turns. Then start adding caps and see if it starts binding. If that's all good check the clearance with some plastigauge or something. Idk off hand what the range should be, I've never had a reason to check, but I'd wager it should be 0.001-0.0015"
 
That's a bit more than I'd personally like to see. Clean it up lightly oil the journals and cam and put the end caps on, see how it turns. Then start adding caps and see if it starts binding. If that's all good check the clearance with some plastigauge or something. Idk off hand what the range should be, I've never had a reason to check, but I'd wager it should be 0.001-0.0015"
They spun well before i took it apart. I just wanted to look while head was off. I dont like seeing scratches at all. Just not sure whats "acceptable" and Im addinf springs and retainers.

Ill clean them up a bit and see what they look like. Im reading 1500 to 2000 grit.
 
This is just my opinion.
If small scratches by debris or dirt is the only issue, cleaning a little bit with sandpaper should probably work. But your case may be different, as I see in the pic that you have run the engine with almost no oil pressure in the head or maybe even no oil. So in your case journals are possibly deformed. So first, I would be worried about the journal roundness and straightness more than scratches.
I am not saying that sanding by yourself wouldn't work for your case, maybe work maybe not. And I know it would cost you more money and time, and don't want to say negative thing to discourage. But if you don't want to take any risk, maybe it's better to ask a machine shop that can inspect and do a cam line honing or boring the head or just find another good core if necessary. That would cost more but the safest.
 
This is just my opinion.
If small scratches by debris or dirt is the only issue, cleaning a little bit with sandpaper should probably work. But your case may be different, as I see in the pic that you have run the engine with almost no oil pressure in the head or maybe even no oil. So in your case journals are possibly deformed. So first, I would be worried about the journal roundness and straightness more than scratches.
I am not saying that sanding by yourself wouldn't work for your case, maybe work maybe not. And I know it would cost you more money and time, and don't want to say negative thing to discourage. But if you don't want to take any risk, maybe it's better to ask a machine shop that can inspect and do a cam line honing or boring the head or just find another good core if necessary. That would cost more but the safest.
I will be brining to the machine shop to inspect as well. Theu suggested the same. Your input is appreciated!
 
I will be brining to the machine shop to inspect as well. Theu suggested the same. Your input is appreciated!
I use 220 grit sand paper and clean them up with my fingers. That will get them glass smooth by itself usually. I have repaired and ran far worse than that.

I never step it down anymore than the 220 either. Obviously if you do it only gets better from there.
 
on more worn engines you can just adjust for some lost oil pressure by running a heavier oil, this does look like more wear than you would normally see even for an engine with high mileage but its possible that it just spent too much time at low idle and starved the heads of oil, your caps do have some lines from small debris going through them but whats more concerning is how glazed and shiny they look which means they were run pretty dry, hopefully your rod bearings look good
 
on more worn engines you can just adjust for some lost oil pressure by running a heavier oil, this does look like more wear than you would normally see even for an engine with high mileage but its possible that it just spent too much time at low idle and starved the heads of oil, your caps do have some lines from small debris going through them but whats more concerning is how glazed and shiny they look which means they were run pretty dry, hopefully your rod bearings look good
I have rod knock... doubt my rod bearings are good... just hoping head is not trashed too
 
I’ve posted way worse pics than that, and got a mixture of responses but several of them were that cleaning them up should be fine. Assuming the oiling system is repaired/working properly. FWIW, I ended up with another head.
 
I’ve posted way worse pics than that, and got a mixture of responses but several of them were that cleaning them up should be fine. Assuming the oiling system is repaired/working properly. FWIW, I ended up with another head.
Why did ypu end up with another head
 
Why did ypu end up with another head
Mine way was worse than these caps, and the lower part of the cam journal was damaged enough to even make the oil hole look a little closed up from being grinded on by the cam. I wasn’t desperate to try to run it, so I made the choice to build the most reliable version of the car as I can. That’s also why it’s been sitting for four years, unfortunately.
 
Mine way was worse than these caps, and the lower part of the cam journal was damaged enough to even make the oil hole look a little closed up from being grinded on by the cam. I wasn’t desperate to try to run it, so I made the choice to build the most reliable version of the car as I can. That’s also why it’s been sitting for four years, unfortunately.
Fair enough.. mine are cleaning up super easy with 1500grit wet sand. Ill still have machine shop test tolerances

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I have rod knock... doubt my rod bearings are good... just hoping head is not trashed too
that would explain the low oil pressure, as long as the head gets oil from now on you're fine, the caps actually look pretty good but you should go ahead and run 5w30 or 10w40 to be safe. btw as long as your rod bearings haven't eaten all the way through their aluminum layer your crank will be fine. and remember to install the caps in the correct order and direction because they're all different.
 
that would explain the low oil pressure, as long as the head gets oil from now on you're fine, the caps actually look pretty good but you should go ahead and run 5w30 or 10w40 to be safe. btw as long as your rod bearings haven't eaten all the way through their aluminum layer your crank will be fine. and remember to install the caps in the correct order and direction because they're all different.
Always run 20w 50.. motor was built for that

My story sucks.. short of it is a friend helped me when i was injured and skimped on 25 cent squirter crush washers so 2 dropped out... got low oil pressure briefly 9psi idle and would come uo on revs. But this was at filter housing.

There was no knock yet I fixed everything put motor back in and after a couple start ups it was there.
 
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