Cam Caps chewed up *pics*

[grimreaper]

i can feel the ridges on a few of them. Mainly near the cap meets the head, cam is ok except the 2nd bearing which has some groves i can feel. Head journals have pitting of little pieces and is fairly rough again mainly on the sides right where the cap meets the head. Is there anything i can safely do to save the head?

this is what happens when you dont tq one bolt on a cam cap down, chewed the #2 journal pretty good...

 

[grimreaper]

more

 

[gaboonviper85]

I've seen this on two 7m heads....I've only seen 3 7m heads so far so I have a feeling this kind of damage is common....personally I'd run some scotch-brite over them to remove the burrs and reuse it....wish they had replaceable bearings but shit in one hand and want in the in the other and see which one fills up first.

 

[92TealSupra]

I have taken apart I think around 4-6 7M heads. It's better for the wear to be in the middle, but what I am looking at is still quite normal. The 7M is a good motor, and the oiling is decent, but this is common. I have never seen a 7M head that didn't look like yours.

 

[Poodles]

Need pics of the cams.

For the most part it's normal as the steel cam wears on the aluminum and builds up material and then the wear stops. Was the engine recently rebuilt with head work?

 

[grimreaper]

guess thats good then, my exhaust cam is fucked though. the cam took a beating from the loose cap. pretty decent grooves in it.

poodles: yes according to the previous owner it was pulled apart for MHG prep and he found everything in the bottom end to be with specs and the head had a basic head job $4-500 worth of work per receipt. why?

pics make it look better then it feels , its quite rough...

 

[CyFi6]

Quick question, how did you get your upper timing cover off without removing the thermostat housing?

 

[IJ.]

This happens when using bypass filters for too long

"normal" is gouged up and missing babbit material on the Cam Journals not gouged up tunnels.

 

[grimreaper]

^ thats what i thought, new head or a would new cams and the tunnels lightly smoothed suffice? right now new head is last on my list if it can be helped....

MAGIC
























lol, i left it off from the front seal replacement 500 hundred miles ago

 

[IJ.]

The head "could" be reclaimed by taking a skim off the top surface and caps then line boring and honing back to suit the cams after they've had the journals linished but as always it will cost.

 

[CyFi6]

I don't mean to thread jack, but when i had my head work done i had the whole head media blasted, and the journals on the head(not the caps) were blasted as well, leaving a frosted type finish, I've been using the car for a few thousand miles since with no issues, but should there be any concern about this?

 

[grimreaper]

The head "could" be reclaimed by taking a skim off the top surface and caps then line boring and honing back to suit the cams after they've had the journals linished but as always it will cost.

fun fun, ill probably source another head, although for right now its going back together with a new cam... i dont have a choice other wise id leave it in pieces for good in storage

can scotch brite to "lightly" smooth the surface do for the time being? nothing aggressive, and the journals will get plastigauged for over all clearance (now that i know which part to shave down )

 

[grimreaper]

I don't mean to thread jack, but when i had my head work done i had the whole head media blasted, and the journals on the head(not the caps) were blasted as well, leaving a frosted type finish, I've been using the car for a few thousand miles since with no issues, but should there be any concern about this?

pics? does it look like little "meteors" hit the surface? little chunks missing?

 

[Poodles]

Honestly they don't look too bad...

Though the cam lobes look a bit bad as well...

 

[grimreaper]

thats lint, lobes are perfect with no scoring. looks just like scoring of some sort though..

 

[CyFi6]

pics? does it look like little "meteors" hit the surface? little chunks missing?

No pics, but not quite "chunks" taken out. Just a smooth, even matte finish. I think that's the best way i can explain it, as i cant find any pictures of anything like it. Basically, it no longer had the shiny almost mirror like finish.

Theres a before pic (sorry not the greatest) but you can see the shiny finish on the cam saddles.

 

[grimreaper]

i cant see that far, smooth bores?

sad to say it but im just going to touch up the caps with a scotchbrite pad (for now), a GOOD head is like a needle in a hay stack....

 

[suprarich]

Like IJ said, linebore the cam tunnels and it is good as new. Do it after the head is milled so that the cams are parallel to the gasket surface.