Differential Refresh

 My next quest was to eliminate the leaks out of the differential (rear end).  So while the rear suspension was out, I dropped the entire differential, cross members, and drive shaft.  The transmission must be drained before trying to pull out the drive-shaft!

Next I removed all of the pieces from the differential, including the half-shafts

I then began to work on the side seals, as that was new territory for me.  After removing the half-shafts, its as simple as removing the the center bolt and pulling out the axle stub.  I'd recommend working on one side at a time, rather than pulling the entire thing apart.  Also, its easier if you drain the differential before you start pulling the seals out.

 

Keep in mind these are keyed (one side does have a flat-face)

Below is the old side-seal installed, followed by the new Beck Arnley seal which I'm replacing it with.  Like with replacing an oil-filter, I did smear some differential fluid on the new side seals before I inserted them.

After buttoning up both side seals, I pulled off the rear differential cover to clean the surface and replace the gasket.  I did use a very very very thin layer of high-temp RTV.

   

 

Reassembled and on the jack ready for installation

Everything back together and new license plate installed; ready to cruise!

Suspension Rebuild

The next (big) project I have for the 240z is to rebuild the entire suspension system.  I recently picked up the Tokico suspension package for the 240z off of Amazon.com (free Prime shipping) as well as the Energy Suspension polyurethane bushing kit.  Although I need to save up for the rest of the parts I need, I've been carefully planning and preparing.

Check out this great site with pictorial instructions on replacing the struts/springs:

• http://atlanticz.ca/zclub/techtips/suspension/tokicoupgrade/tokicoinstallfront.htm
• http://atlanticz.ca/zclub/techtips/suspension/rearend/index.html

My shopping list of additional parts includes:

• MOOG U-joints (driveshaft & half-shafts)
• Rear spindle pins & lockbolts (maybe)
• Outer tie-rod ends
• Ball joints
• Strut mounts
• Front strut bearings
• Differential seals (sides, rear, pinion)
• Half-shaft boot kits
• Transmission seal (rear)
• Rustoleum professional rust-primer, enamel, and TSP

Tokico suspension kit (springs, strut inserts, gland nuts)

Energy Suspension Polyurethane Bushing Kit

 


FRONT SUSPENSION
Removal of the front suspension members went fairly well.  My impact wrench and shop-press were life savers and time savers; I highly recommend getting proper tools if you tackle this job.  While pressing the outer bushing sleeve out of one lower control arm, I did end up deforming the piece.  Luckily I was able to pick up a replacement on eBay for a very reasonable amount.

While everything was apart, I did clean the parts with TSP and then primed and painted with Rustoleum Professional enamel.

The new strut inserts and springs assembled very easily and the replacement tie-rods and ball joints fit perfectly.  The only issue I had was with the rack & pinion boots being a little short, but I was able to modify them to make them work properly.

Dirty & grimy pieces

Looks like something is missing

Damaged LCA

Painted & ready for reassembly

REAR SUSPENSION
Thanks to the help of my dad, we began to pull apart the rear suspension.  Everything seemed to be going easy until the dreaded spindle pin removal of the first control arm.  It wasn't nearly as bad as many of the stories I've heard, but not fun and not as easy as the service manual shows (see picture of just pulling the pin out).  Then came the removal of the bushings which proved to be a challenge again.

After breaking my 12-ton shop press, I decided to go another route of using an air hammer to knock the bushings out; that proved to work very well.  When I went to tackle the other side, everything came apart much quicker since I knew what I was doing.  Now its onto paint and reassembly.

 

Vintage Road America pictures

I sorted through a lot of my parents old pictures and pulled a couple good ones out from the early 80's

Electric Fuel Pump Installation

In an effort to make the 240z more reliable, I've decided to upgrade to an electric fuel pump and then retire the mechanical pump.  By using quality parts and a smart plan, this will prevent vapor lock, keep the float bowls properly filled, and should allow for the car to start easier.

Parts List

• Fuel Pump (low pressure, 4.5PSI max, 30GPH): Airtex E8016S (~$38)
• Oil pressure switch: Airtex OS75 Safety Switch Oil Pressure (~$15)
• Mechanical fuel pump block-off plate (~$25)
• Brass "T" (1/8" FIP): Watts AC-704 (~$5)
• Brass male-male (1/8"MIP 1/8"MIP): Watts AC-714 (~$2)
• 30amp automotive relay: Dorman 84601 (~$5)
• inertia switch (optional)
• Wire, fuses, and miscellaneous connectors
• Fuel Hose

My first step was to plumb the engine block for an Oil Sensor Safety Switch.  As you can see from the picture below, I inserted a "T" joint to allow me to keep the current oil pressure gauge (second picture) as well as the new safety switch.

Next I needed to design a reliable and safe wiring scheme which would incorporate the factory wiring for a fuel pump but also allow for the safety switch and relay.  In the diagram below, the GRN wire and the BLK/WHT already exist in the wiring harnesses; the plug is just taped to another set of wires below the fuse box.

Wiring Diagram, designed and drawn by me

The fuel wire harness is held with blue tape (see circle).  The BLK/WHT wire  is live with the ignition switch.  The GRN wire goes back to the fuel pump (wired from the factory).

There are two unused harnesses.  Left is the Fuel Pump, right  is the Fog Lights

New electric fuel pump.  I ended up using an existing bolt/nut for the mustache bar to mount the pump.

Relay with the initial wiring

Relay once the wires were bundled nicely

Oil pressure sender initial wiring

Oil pressure sender wires bundled nicely

Mechanical fuel pump block-off plate

Coolant recovery tank

Today I installed a universal coolant recovery tank since the 240z didn't have one from the factory. Now that I've replaced the gaskets, the overflow tube on the radiator has been spitting coolant onto the ground.

The only available spot for the large universal tank was in front of the radiator.

Thermostat housing gasket

I think I found the last coolant leak on the engine. The thermostat housing always hisses when the car is turned off. I did unfortunately break a bolt off in the cylinder head!! Luckily I was able to get it out without drilling.

New gasket installed! No more hissing when I turn the car off & no more coolant leaks!

Housing and the (lack of) original gasket

Yes, I broke that bolt off in the head

Glad I had a couple spare bolts laying around

NOS Fuel Pump

So I ran across a NOS electric fuel pump which after investigation appears to be from a Datsun 720 pickup truck.  Its never been used and I'm hoping to sell it to someone with a 720 who can use it for a restore.  Unit number 379-00160, Transistor Fuel Pump is listed on the label.

I was able to power up the pump and it works great.  Also appears that this was used for the '73 240z's that experienced the vapor lock conditions.  After opening the filter lid (right side of picture), I can verify this pump has never been installed!  Another NOS part that I can sell to allow me to purchase some more parts for my restoration.

Vacuum leaks and exhaust pops resolved

I decided to pull off the air pump and associated devices which no longer function due to their age and the fact that we no longer have leaded gasoline.  The popping out of the exhaust has ceased and I am no longer introducing un-metered air into the mixture.  A couple more quick fine tuning and the car will be running perfect!

Back up & running

The carbs have been re-installed into the car and it fired right up.  I've done the gross tuning and now I just need to fine tune the mixture.

New thermostat

While the coolant was drained, I decided to install a new thermostat. Look at the old one I pulled out! I can't imagine what the rest of the cooling system looks like... That is for another day though.