Am I screwed. I was in a hurry trying to get my head bare to get it machined and I didn't think to remove the cam cap bolts in the specified order in the repair manual.

The book suggests that it can mess up bearings and bend the cams.

I feel like a massive moron. At least I had the brains to loosen em all slightly rather than just unbolting each cap and moving on.

Is this common to warp the cam?

Just another thing to worry about after dealing with a blown head gasket!

 

You're totaly fucked.

Did you lossen them a little at a time? You are probably fine.

 

You're probably fine, I've heard that it's possible to bend stuff if you do it in the wrong order, but I've never heard someone say it actually happened to them. If it were me, I'd bolt the cam back in (sequencing it per the manual this time) and see if the cam still turns smoothly. If so, I wouldn't worry too much about it.

--Ian

 

It's perfectly fine. If you're paranoid, do what codrus suggested above, but I wouldn't even give it a second thought.

Personally, I have never heard of such a thing. You crack the bolds lose in a rotating pattern, and then remove as you go. I have never seen that to be a problem.

 

It never even crossed my mind that it would be a problem.

I loosened each bolt a bit moving from cap to cap down the cam to the other end then on the next cam and did the same and then removed each bolt and then cap starting where I began.

In my mind the only way this could warp a cam is if the head is warped but if this was the case then the cams wouldn't spin off the block and would need the head bolted to block to correct the warp and be flat again. Which means all cylinder heads are warped.

Have any of you ever removed cams in a fancy unbolting process?

 

I remove cams in a fancy unbolting process, but only because i've done it enough times that i don't have to look up the pattern anymore.

I don't think it really matters. The point is that you do each one a little at a time to relieve stress.

 

I have removed the cam caps in just about every oder imaginable on a miata head over the years. I have just always done a little bit at a time on each bolt then moved on the next. Never had an issue with any of my cams.

 

Thanks for the replies guys. It eases my mind I thought I might be buying new cams for a while there.

 

Theoretically it can cause issues, but in reality it's difficult to actually mess it up.

Head bolts are another story, though. Loosen those end-to-end and you run a real risk of warping the cylinder head a little bit.

 

^^ crap.

Didn't know this. Checking and correcting this should be part of the head rebuild process though correct?

 

The reason for loosening the cam caps in the right order is to prevent bending the cam -- if you should manage to do that (unlikely), the cam is junk, you'll never bend it back to straight.

I think this is something that's more of a concern on a motor with hollow cams.

--Ian

 

If you removed them already and they are intact they are fine... it's usually more of an issue if you remove them when not at TDC and there's lots of pressure on the lobes. Just don't install them that way. Seen dudes enter snap city on brand new cams that way... lol.

 

The timing belt was off and the head off the car before I removed the cam caps and bolts.

 

I've heard of cams cracking if you tighten one side down with the other loose. I've seen people bend valves if the cam is off time while its tightened. All the hip new cars nowadays use fancy hydro formed hollow cams that you have to be extra careful with.

 

Fortunately, the BP is decidedly unhip. It's so unhip, it's a wonder our bums don't fall off. We have solid cams, and we have a non-interference engine where the pistons don't rely on timing to avoid hitting the valves.

--Ian