Since my original motor went down with a cracked cylinder head, I started to look for a replacement cylinder head and get the motor back running. I have not been able to find a cylinder hear for a reasonable price so I decided to buy another complete motor(used) and prep it for replacing my busted motor, and also do some performance mods to the car in the rebuild.

I picked up a replacent motor, and it came with the rest of the car minus a bad automatic transmission. The empty chassis will be getting an LS1 V8 installed :) but that's for a future thread. There's a chance it will also get a twin turbo setup on it too
I pulled out the recently aquired 1.6L motor, cleaned it up a bit and bought some replacement parts to prep it for dumping into my 1990 Miata.

I bought a new oil pump, water pump, rear main seal, cam seals, cam sensor o-ring, timing belt, and valve cover gasket.

I pulled the oil pan and found that there was none of that bad oil sludge. The motor was an oil leaker, from nearly every seal and gasket that I saw, but I didn't pull the main caps to check main bearings for excessive wear. I probably should have since I was right at that point. The next time I pull a pan on these motors I'll check/replace the main and rod bearings.
Then I figured that I would like to pull the cam's out since it was mated to an automatic tranny. The cam spec's were smaller than cams on the manual drive train. So, I pulled the cam's from my original motor and swapped them in this replacement motor, and replaced the cam seals and cam sensor o-ring while I was doing that. BTW, when you align the front sprockets for belt installation, the cam sensor will also point upwards for proper alignment. The sensor has 2 tabs and 1 of them has the timing mark that will point up when the other sprockets are up.

The new oil pump was installed and it also provided the new front main seal. I pulled the rear main cover off and replaced the rear main seal, cleaned off the old goop on the cover and block, then goop'ed the rear cover and put it back on.
I wish there was a real gasket for the rear cover and oil pan, but oh well. The pan was disassembled and cleaned, as well as the mating surface of the block.
Goop'ed the oil pan and assembled it to the block.

Installed the crank pulley and noticed that it was contacting the oil pump front flange. I tested by pushing a dollar bill in between the parts and it would not slip through. I covered things up with blue towels and manually filed about 1mm off of the flange. Then, the pulley sat without intereference. It was just some extra casting flash on the oil pump. BTW, the crank and key looked good and not worn out of the original groove. I recently picked up a 1.6L motor and it has a bad crank keyway, but that will be for a future thread.

New water pump was installed, but I'll likley not run a heater in the car. I used a heated seat pad when It's cold outside.

I shaved off the mounting flange on the intake runners, I always hated it being in the way when I changed the oil filters. The support bar was removed long ago.
I found a long oil filter that will do nicely for me Purolator 14610. I wonder if there are filters even longer than that one, for this motor.

A new timing belt was installed and I double-checked the sprocket positions, looked right to me.

Next things to do are install the shaved-flywheel, clutch, starter, alternator, and belts. Then, stab it back into the chassis and fire it up.
A performance header(bought it used) to go back on the motor too. It needs a little welding after fitment, but it shouldn't be an issue.
I'll be removing the dash to pull out the HVAC parts and drop more of the weight. I hope that I can keep the dash parts from shattering.
The A/C and power steering parts in the engine compartment were removed and I swapped in a manual steering rack.

So for this rebuild, I've removed alot of weight in the front, dropped some rotating weight, and put on some power performance parts in this car rebuild.

Lowering springs will need to come soon because I can see that the car was riding way-high with some of the weight reduction before I pulled the motor, and now with even more weight reduction with accessory removal it will be even riding even higher.

It's going to be a couple weeks before I can put more time into the rebuild.

Jay Johnson