Jackmaster in 1990 VN Commodore
New Powder-Coated Jackmaster
Tee Piece on Oil Sensor port in 
1990 VN Commodore Sedan
Oil return Connected to Sump (Oil Pan) in 1990 VN Commodore Sedan
Oil Return Through the Oil Fill Cap
Modifying Dip Stick to Return
Cleaned Oil to the Sump - includes 1/4"BSP nipple to attach the hose fitting. - $12.
Installation in a Toyota Hilux 2.7 Diesel.
 Note the swivel return fitting.
For detailed fitting instructions go to "JACKMASTER INFO"
  • A well proven method of accessing oil feed pressure is to use a "Nutsert" which is a  proprietary rivet nut device. This can be used also for returning oil to the sump or rocker cover. For oil pressure pickup the "Nutsert" is fitted to the end of your full flow filter which is under full engine oil pressure while the motor is running. It is a good idea to have a couple of new full flow filters done at the same time. As the full flow filter does not need frequent changing when using bypass filtration they will last you for a long time. For oil return a "Nutsert" may be fitted to the side of the sump or rocker cover. I have supplied a very interesting download below the pictures. I found it on the web. Full credit to Brian Brown for this brilliant installation method for "Nutserts" without the use of the special "Nutsert" installation tool.
  • The swivel return fitting provides the most effective way of returning oil and is fitted in the oil filler cap. Oil flow can be checked with ease while the engine is running. This is a good idea as you are always able to see that the oil filter is flowing.
Swivel Return Fitting on a Toyota Surf. 
Swivel Return used on Ribbed Oil Cap.
(Click on pic for clearer image)
On this Toyota 1KZ Hilux the oil filler Cap has a centre rib. You have the option of getting a flat top cap from the wrecking yard or modifying the existing cap. In this installation the cap was placed in a lathe and the rib was drilled with a 19mm drill, down to the bottom of the rib. The hole was completed through the cap with a 10mm drill. The rubber seal on the swivel was then used on the outside of the cap, instead of inside, as on the flat caps. The large, flatwasher was then used on top of the rib and the 3 small spacing washers were discarded. Click to enlarge picture.
Swivel fitting for Oil Return.
This is an excellent way to return oil to the engine by drilling a 10mm hole dead centre in the oil filler cap. This allows for many options such as, partial oil changes and oil removal simply by removing the cap while the engine is running and allowing the fitting to pump oil into a container. Some diesel owners remove a litre of oil occasionally and put it in the fuel tank. It is then used as fuel. A perfect way to recoup the cost of the oil and at the same time add new oil to the engine. They find that oil changes are eliminated totally.





by Brian Brown



This is how I install nutserts without the special tool. I'm sorry I didn't get this posted earlier.

Start out with a strip of 12 gauge steel about 12" X 1". Near the end drill a clearance hole of the appropriate size for a bolt that fits the nutsert.

Get a long class 10.9 bolt (same thread size as the nutsert), nut and flat washer.

Thread the nut onto the bolt until it's near the head of the bolt. Slide the flat washer onto the bolt. Now stick the end of the bolt through the hole in the steel strip.

Thread the nutsert onto the end of the bolt until the end of the bolt is flush with the bottom of the nutsert. Slide the steel strip and the flat washer up against the face of the nutsert.

Lubricate the bolt thread that's now exposed between the nut and the flat washer with a molybdenum lubricant (doing it at this point minimizes getting lubricant on the nutsert threads). Thread the nut down until it touches the flatwasher.

Push the nutsert into its hole.

Use two wrenches. One to hold the head of the bolt stationary. One to turn the nut. The steel strip should also be held stationary.

*** This is the key point *** By holding the steel strip and the bolt stationary, there will be no twisting force applied to the nutsert as it is tightened. As the nut is turned, the bolt will be pulled straight out, collapsing and seating the nutsert.

When the nutsert is very tightly seated, loosen the nut a little and then unthread the bolt from the nutsert.

Using this method with the steel strip, you should have no problem with nutserts being loose. I've installed many nutserts this way without any problem (although I still haven't put an X - brace on my car. This summer I hope!)

I hope this helps.

Brian Brown


September 17, 1999