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Based on the attached photos, what are your thoughts on the likelihood of this head needing replacement?

The situation with this 01 Civic I bought is that it has been overheated (possibly WAY too much). Before I bought it, I did a cylinder leak down check and saw bubbles in the radiator when the gauge was at the #1 and #2 cylinders. So now I've pulled the head and I'm a little worried about what I found.

There are scratches on some of the cam lobes as well as some of the cam followers/rockers. The scratches on the rockers don't 100% match up with lobes that have scratches.

But one of the most concerning issues is that inboard section of the plastic timing cover is melted. It was deformed enough that the cam timing gear began to etch some of the melted portions of the timing cover and one of the bolt head was obscured by the plastic. I worry that if the engine was heated enough to distort the plastic timing cover that the head, at best, may be too far gone for a machine shop to fix.

I'm a little worried about the bottom end bearings after seeing this; whatever galled these surfaces could have also found it's way to the crank journals.

When I pull the oil filter, I'll cut it open and look inside for anything shiny, but that'll be down the line at least a week.

Since I can't get the head to the shop for a couple of days, I thought I'd see what the forum thinks of what I found.

Also, if you have a part number for that melted chunk of timing gear cover that you can share, that'd be great.

 
Rep Power: 518

Minor scratches may not be unusual to see, and .........if it was running before you took it apart, was it unusually noisy?


When the head warps it literally bends upward in the middle, which can put a hell of a lot of stress on the camshaft. . The camshaft spinning while the head is overheated and distorted could be the cause of the scoring
Visualize this in your mind then inspect the upper half of each cam journal for scoring.


Melted plastic....that's freekin hot. I'm almost certain the head is warped
If the machine shop is good and they know exactly what the head is for, they should be able to look up specs, measure and determine if it needs replaced (warped beyond max spec or total height out of spec)
I'd wonder if piston rings were damaged,
and if the neck of the radiator was burned out from steam erosion
Did the top radiator hose crackle inside when squeezed?

 
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The vehicle sounded just fine to me when it was running, prior to pulling the head. I didn't hear anything but what I thought was a smooth running Honda.

I WAS supposed to have this head at a shop today, but one thing lead to another and it'll be at least a week before it goes anywhere.

The upper radiator hose didn't feel like anything more than just a hose to me. No snap-crackle-pop. Should that mean anything?

 
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Just for reference, even though the shop took two weeks longer than they had quoted me, they said the head turned out A-OK. I really expected to have them to try to sell me a different head after seeing that it got hot enough to melt the plastic bolted up to it.

I bought new timing belt covers to replace the melted ones and I'm about 90% through the re-install. I expect no problems when it comes time to start up with the rebuilt top end.

These engines are tougher than I expected.

 
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Quick follow up. The head seems to be fine. After the install, I haven't been able to do much but surreptitiously drive around a large parking lot, as the vehicle is waiting for plates and pink slip to come in the main, but the engine comes up to temp quickly; up to 35MPH, the limit I can safely get to in said lot, everything is just peachy.

All the way up to the RPM limiter is smooth as can be.

So, even with the head getting hot enough to destroy items around it, it was able to be machined back into a working piece.

Great job, Honda!