Cyl 6

Cyl 5

 

Cyl 4

Does the oil flow around the cam tower mounting bolt? It would have to right? And what about the mouse trap springs could they get weak with age and cause a problem?

 

Edited June 9, 20177 yr by J Shara

On 2/13/2017 at 4:47 PM, J Shara said:

 I rebuilt the engine but had the head sent out to Mancini machine, where I know they re surfaced it, and I can only assume they checked, repaired, and assembled the head correctly, as this was some years ago.  I was driving the car one day and I thought the valve train sounded louder than normal so I preceeded to pop the cover off and check my valve clearances. I found that a few lobes on my cam are black, not shiny like the others. I also noticed that the oil is dark for how new it is. I'm wondering if I ran the valve clearances too tight on these valves and damaged the surface hardening of the cam. I ran Lucas oil stabilizer in this engine when I was driving the car as well. Also used some ethanol fuel treatment in the gastank. Any feed back would be greatly appreciated. 

They don't look good.  If you had lash set too tight what would happen is that the base circle would get shiny from the rubbing of the rocker arm (the base circle is where the gap or lash is and normally only feels the light pressure of the anti-rattle spring), and you would burn the valves that are set too tight because they wouldn't close completely and would over heat.  As I understand things.

It does look like you just have low volume of oil passing over the lobes, causing overheating.  Lucky that you stopped quickly, the cam looks saveable.

I might check the oil pump.  The way the system is set up the head gets low flow, controlled via a small orifice in a plug in the head's oil passage, and most of the oil is routed to the crankshaft, where the forces are much higher.  That's my guess - oil pump going bad.

Or the orifice in the block itself is clogged.

Actually, I'm going to change my guess to sludge in the spray bar.  The spray bar is a piece of cake to remove.  Maybe you already took it off.  Just noticed that you blew air back in to the cam towers.

Anyway, jumping to "remove head" seems premature.

Edited June 9, 20177 yr by Zed Head

On a side note, just picked up a 79 L28 with matching 5 speed trans lol. Just to have it. ? It's an F54 block and a P79 Head. I've heard different things about the P79 head and when I get around to rebuilding/modifying it, I may just buy a different one.

The head bolts go through the far left holes in my picture. The cam tower bolts go through the two that are in line with each other. The oil feeds are the smaller holes to the right. Hope you can understand my backwards arse thinking/splainin'.

The paper gaskets between the spray bar and towers could have moved and blocked the flow?

Seems reasonable.  Or maybe they swelled after installation, after the machine work.  Should be easy to see by eye.  We need that picture.

How many miles on the "new" head?

Gotta give her a bath too

Just over 1500 I believe. 

15 minutes ago, siteunseen said:

The head bolts go through the far left holes in my picture. The cam tower bolts go through the two that are in line with each other. The oil feeds are the smaller holes to the right. Hope you can understand my backwards arse thinking/splainin'.

I'm mistaken and sorry for that but it's been over my minds time limit.

The head bolts don't go through the towers I don't think, the line up dowels do.

Again I'm sorry but I have early onset of dementia. Too much sun has fried my mind like those eggs on the drug commercials.