While working on the rear end I got a much better look at the dual
exhaust setup that came with the truck. What I saw did not impress
and I pray it was not done by a muffler shop.
The whole setup was pretty cobbled together from the horrible mounts,
poor bends and craptastic second tailpipe addition. I had planned on
replacing all of the gaskets at the flanges due to an audible
exhaust leak so I started pulling the system apart.
Turns out the
exhaust leak I was hearing wasn't one of the flange gaskets but a
much bigger leak on one of the exhaust pipes where it had corroded
I ended up
ordering a replacement setup from AutohausAZ for roughly $180.
Losing the dual exhaust pipes did not bother me as I figured they
would get crushed on the first ledge I dropped off of.
It was finally time to start on the engine. The first thing I removed was
a sign of things to come; the factory air box was cracked around one
of the mounting tabs. Some shoe goo and drywall tape from my RC car
supplies made for a sturdy repair. As mentioned all of the vacuum
hoses I was removing were in terrible shape, many crumbling at the
ends so I was going to replace them all when everything went back
Next up was removing the supercharger to gain access to the valve
covers. Here’s where things got real interesting. I removed all
the bolts that hold the S/C to the intake and upon removing it just
fell apart in 3 pieces. The wastegate actuator mounting tab fell
off and the rear mounting tab at the base of the S/C was still
sitting in the truck. Now normally I would chalk this up to myself
but all signs pointed to the previous owner. On closer examination
I noticed both broken parts had been glued back on using what looked
like gorilla glue. That in itself isn’t enough to incriminate the
previous owner except that the same adhesive was used elsewhere.
While working on the truck I discovered the same hard epoxy was used
to seal the rear 3rd member and to glue the driver’s side
mirror onto the mirror stalk.
The buyer’s remorse kicked in at this point because without the S/C this
truck was not a good deal. After a few days of contemplation I
decided to try repairing the S/C housing with some aluminum brazing
rod as seen on YouTube. While waiting for the rod to arrive in the
mail I fabricated a fixture to hold the broken mounting tab so the
bottom mounting surface would be flat. Once the brazing materials
arrived I used a torch to heat the S/C housing but could not get the
brazing rod to adhere well. I did manage to get the wastegate actuator mounting tab re-attached by drilling
and tapping the S/C housing and bolting the tab back on using some
Plan “B” was to try TIG welding the
mounting tab but I do not own a welder capable of welding aluminum.
Luckily my neighbor had a friend who could do it so after some more
prep work I took it over and had the tab welded back on. Since
I did not want to have to re-surface the mounting flange I planned
on using JB weld to fill in the crack on the inside of the manifold
and on the bottom surface. I
Next up was pulling the valve covers and installing new seals. All signs
were pointing to these being the source of most of the oily residue down the
side of the engine block.
Once the valve covers were re-installed I moved on to the timing belt and water
pump. Both were in really good shape so maybe the 150k timing belt change
sticker was not the most recent service. Either way I replace the belt,
tensioner, water pump, thermostat and related gaskets. The job was pretty easy
once I made a tool to hold the lower main pulley.
While I was digging into the engine bay I realized I was going to have
to change out all of the vacuum lines since the existing ones were
all cracked and brittle. I ended up ordering a whole box of
different sizes from Summit Racing since they had everything I
needed for .99 cents a foot. One thing i missed was a 3 foot
piece of 1/4" fuel line to replace the fuel return line with but
luckily the local auto parts store had some in back.
The last modification I chose to do was to re-route the transmission
cooling lines from the lower part of the radiator to a dedicated
cooler. This takes care of a common issue with older 4Runner's where the internal cooling
passages crack allowing the transmission fluid to mix with the
anti-freeze. This typically takes out the transmission if not
caught immediately and I figured with all the miles on this
particular radiator a $50 transmission cooler would be cheap