You must fit your primaries to the engine before you fit the dry sump tank.   The space the tank resides in is needed during the install process. If you have not fitted the exhaust primaries yet, then do this now, following the steps as described here.

My kit was supplied with a grub screw bung for the oil temperature sender and a spare temperature sender. The 420R doesn’t have a gauge for oil temperature, but it is possible to install a switch to switch between water and oil temperature at a later date, if you install the temperature sensor in the oil tank. Even if you have no intention of fitting an oil temperature gauge, you will have to remove the grub screw bung and seal it with PTFE tape or a sealant of some sort. Mine was only loosely fitted and would have leaked oil.

I sealed the new temperature sensor with Loctite 567 and secured it in the dry sump oil tank. The sensor is imperial, so I used a 1/2” spanner. The grub screw was also imperial and I used a 3/16 Allen key to remove it.

Next, I installed the P-clips on the lower chassis tube with a bit of rubber lubricant, because I am going to move them into place once the dry sump tank is lowered into position. I made sure they were the correct way round: the tail of the P (the mounting hole) should be pointing towards the front of the car (away from the engine).

Lowered dry sump tank into position

I protected the tank with a couple of clothes as it was lowered into position. 

Attaching the tank with the three bolts was simple enough. The bottom bolts had a washer top and bottom and a nyloc nut. The top cap head bolt on the other hand will need a replacement. As expected, there is a gap between the mount and chassis. Other build blogs I’ve come across resort to using a couple of washers to bridge that gap, but I have chosen to purchase a aluminium spacer for the 7mm gap; I found the spacer on eBay.. I am also going to replace the top bolt with a 5mm longer version to get the desired amount of thread engage in the chassis.

The next problem I encountered was caused by my wheeled axle stands.   The width and depth of the stand is going to prevent me from fitting one of the dry sump hoses.  The hose in question goes from the front sump connection to the oil cooler.  This hose has now been removed and will be refitted when I lower it down towards the end of the build. I prefer to have a struggle with one hose later than losing the height off the ground for the rest of the build. 

Fitting the bottom hose was just a case a locating the hose and tightening it by hand. The rest of the dry sump hoses will remain hand tight until the radiator is fitted and I can set then into their final location and tighten. I tie-wrapped the dry sump hose from the back of the sump to the lower dry sump tank connection to the frame.  

Engine breather fitted

I cut the breather hose to length and fitted it. The original P-clip used to hold the hose was turned upside down to create a smooth route to the dry sump tank.

Tools used

  • 10mm combination spanner
  • 1/2” combination spanner
  • 3/16” Allen key
  • 10mm 1/4” drive socket
  • 1/4” drive ratchet
  • Knife
  • Side cutters