Day Sixteen - Pulling off the head

Cleaning the oil pan

Wasn't sure how I was going to tackle removing the pistons yet, so I decided to start with a cleanup job first. The oil pan was filthy and I wanted to clean out any residual particles that may have fallen into it. I noticed what I thought were shavings from the destroyed bearings, so I had to make sure none of that was lingering. Using a bunch of engine degreaser, a bunch of old towels and some elbow grease, I think I got it looking pretty good.

Removing the head

So I had to eventually bite the bullet and get to it. I marked each of the 10 head bolts and removed them in sequence. I was trying to be careful with every little thing. I got a chance to see what a 147K+ mile engine looked like. I didn't really know what to expect. To my untrained eye, it was interesting to see all of the carbon buildup. I suppose it makes sense though. I took a lot of reference pictures, figuring I might need to show them to others for advice. 

I was particularly interested in seeing how the cylinders made out. Again, without any experience I was just making guesses. They seemed to look alright and I didn't see any scoring that I was afraid would have come from the destroyed bearing. I took reference pictures of the valves. You know, just take pictures of everything I thought.

Removing the pistons

Next came time to remove the pistons. One by one I unbolted the rod caps and slid the pistons out, making sure I labeled which one was which. I wasn't sure what I was going to do yet, so labeling them still seemed the most prudent thing to do. With all the pistons out, I got a good look at the crankshaft rod journals and they didn't look so good. Especially the one with the spun bearing. 

I boxed and labeled the pistons. Not sure if I was going to use them again. From what I read, it looks like I would go the over-sized route, which meant buying new pistons so the cylinders could get bored out. Of course, this required some consultation on the part of others who have more experience with this than me.

 I was done for the weekend. Off to do more research on what I'm getting myself into. Heh.

Day Thirteen - As I expected. Problem confirmed

Getting to the bottom of this. No pun intended. Bullshit, pun intended.

Prologue: So I'm realizing that I'm a crappy blogger. This blog fell off the wayside while I was working on the car. (I'm more of a doer than a reporter, I guess.) Anyways, as of today, the rebuild is done. (I'll keep you all in suspense on whether it was a success or failure.) I'm coming back to this because I do want to chronicle the process. I learned a lot! It'll just have to be in retrospect rather than as it happened. I have a large repository of photos that I did take along the way, so hopefully that will jog my memory. Okay, so where was I...

Mounting on the engine stand

Removing the A/C bracket

Coolant pipes off

I had trouble finding bolts that would fit the holes on the transmission side of the engine. Hardware stores do *not* have metric bolts with M12 x 1.5mm thread size. They had 1.25mm & 1.75mm, but *not* 1.5mm! Frustrating!  Had to special order them.

Later I found that it was possible to mount on the side and got some clarity from this thread http://forum.miata.net/vb/showthread.php?p=2155238#post2154806 that I googled.
I had to get different bolts for this method so back to the hardware store again! But this time, they had the right thread pitch, just not the right length. Too long! Awesome. However, with a little on the spot ingenuity in the hardware store, I fixed that little problem by buying some bushings and washers. It took a little finagling with the mounting arms, but managed to get three of them secured. I was a little uncertain just using three mounting arms, but figured the engine is relatively light, so I should be okay. With the engine mounted, I could rotate it and get to the oil pan.

Removing the oil pan

This ended up being a little harder than I thought. I couldn't just pull it off. It was snagging on something on the inside and I couldn't see what it was. It ended up being the baffle, but not knowing a whole lot of what to expect it just seemed stubborn. There was sealant stuck on the cover, so I tried to just pry it up. I bent one part of the baffle a little bit. Hopefully, it wasn't too bad. It wasn't pretty, but I got it off finally.

The first thing I did was look for metal shards. I found a few, I think, and was hoping it wasn't too drastic.

Inspecting the spun bearing

I inspected the rod caps and felt tightness of the rods and it was obvious which one was the problem.

The #4 rod was rattling loose. All of the other ones were tight.

I removed the #4 rod cap and wondered where the bearing was. I was pretty sure there are supposed to be two of these things. To my untrained eye, the single damaged bearing looked ugly, but *how* damaged it was, wasn't apparent to me until I took off one of the normal bearings.

The #4 bearings had actually stacked onto each other and apparently fused together and got deformed from the friction heat. The pictures pretty much tell the story.

Both damaged bearings fused together.

Bearings split apart. 

Journal looks like hell.