Removal of the original engine started with me reading through the workshop
manual to make sure I had the process pretty clear in my head and photographing
every inch of the engine bay to ensure that I had a thorough record of how
every hose was connected (just in case!). I did this because all my previous
experience at installing engines was with so-called "old-school"
V8's and straight 6's. As soon as you lift the bonnet on a modern car, it is
obvious that while reliability has improved out of sight, so has the
complexity. The 180SX has both multi-point Electronic Fuel Injection (EFI)
and a multi-coil (coil-per-plug) electronic ignition system along with a
variety of vacuum and electronic controlled systems. The old V8's with their
carburettor, distributor and points are positively simplistic by comparison.
I took my time and made sure each piece was carefully stored with its
fastenings so that when it came time to put the items back I wouldn't be
scrounging around looking for nuts, washers or whatever was needed. Of course,
this didn't always work, as there were still a handful of missing bolts and
washers that had to be replaced because they had managed to "walk"
from the garage after removal.
Even with starting late on the Saturday and working on my own (with only
minimal assistance from my wife), I had the engine completely removed by the
end of the weekend and had even managed to transfer a few of the items I
wanted to retain from one engine to the other. As I prefer the red rocker
cover over the black, I had purchased a replacement gasket and a tube of
silicone instant-gasket in preparation for swapping the rocker covers. As it
turned out, I needn't have bothered purchasing the gasket as it is made of
rubber and a visual inpection showed it could have been re-used without
While the engine was out, I also had to transfer the flywheel and clutch.
I took a close look at the condition of the clutch while out, which to my
surprise looked like it was an almost brand new Exedy full face organic
clutch. Also, the flywheel and pressure plate showed no sign of heat stress
or scoring. I suspect it had been replaced and the flywheel and pressure
plate machined not long before the car was sold to me.
As the flywheel rotates at engine speed, I took the precaution of replacing
the flywheel bolts and also took great pains to ensure that they were installed
with thread lock and were tightened to the correct tension using a tension
Installation of the new(er) engine back in the engine bay wasn't quite as
straight-forward as removal. After much swearing and pushing and shoving
without any success, I had to call on the assistance of my brother to help me
align the spline on the gearbox with the clutch, while also trying to get the
engine to sit on the engine mounts. While we thought the shaft was in the
clutch OK, we were unable to get the engine to go far enough back to let it
rest on the mounts. In the end, we decided that we were close enough to put
some of the longer bolts that connect the bell housing to the motor in and
(carefully) pull it up by tightening those bolts. I was afraid that we hadn't
actually aligned the shaft and doing this could bend or break something. As
it turned it out, I was wrong, everything tightened up easily and the engine
was now ALMOST on the engine mounts (only needed a millimetre or two for it
to drop on). A bit of levering with a pinch bar and the engine finally
dropped down onto its mounts.
A couple of hours later, I had reconnected all hoses and sensors, filled
the radiator with coolant and was preparing to start it. As this engine had
been sitting unused for some time, I decided I needed to build oil pressure
before attempting to start it. So I disconnected the ignition system and
removed the fuse from the fuel injection temporarily and spun the engine over
on the starter for a period until the oil pressure light went out (I have
since found out that a better method of doing this would have been to
disconnect the crank angle sensor as the ECU would then disable both fuel and
ignition rather than having to do this manually as I had done). Once I had
oil pressure, I plugged everything back in and attempted to start it. It
coughed a few times, but eventually it fired and ran, though rather roughly.
I switched off and went back over the plugs for the sensors to discover that
the Throttle Position Sensor (TPS) connector hadn't quite clicked home. After
rectifying this, it then started instantly, idled smoothly and revved quite
freely. I then took the chocks out from behind the wheels and drove it out of
the garage to take it for a run around the block to see how it would go.
The short run around the block had the temperature quickly building to well
over the normal running temperature. My initial thought was that I had bought
a dud engine and I had just done a lot of work for nothing. After I let it
cool for a time, I went back to the car and removed the radiator cap to check
the water level and found that it needed a couple of litres of coolant, even
though I hadn't lost any that I could see. I topped it up and while I was
scratching my head over where the coolant had gone, there was a loud
"burp" and the water level dropped. In my haste, it seems I didn't
allow enough time for the air to get out of the cooling system. I kept topping
up for quite a while, waiting each time for it to settle, until it finally
would not take any more. I then replaced the radiator cap and took it for
another run, while carefully monitoring the temperature gauge. This time the
gauge sat right where it should and didn't budge. Again, I later discovered
that there is a bung on the inlet to the engine block that should be removed
when filling with coolant to let the air out (you live and learn!).
The engine has since proved to be very reliable and smooth, though not
obviously stronger nor weaker than the engine it replaced (but most certainly