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How To : Inspect Lexus IS300 Oil Pump

Responsible for maintaining oil pressure in your 2JZ engine, the Lexus IS300 Oil Pump is an important part of your Lexus maintenance. If your IS300 oil pressure light is blinking on your dash, you can use our oil pump guide to check and replace your 2JZ oil pump all together. Proper maintenance ensures long life and reliable performance from your inline six cylinder engine.

Of course there are many similarities between the turbo and non-turbo version of this pump. Knowing how to check the 2JZ VVTI oil pump in your Lexus IS300 is a vital part of keeping your Lexus running. If you don’t check your Lexus IS300 Oil Pump regularly, or the oil pressure in your 2JZ, it can lead to premature engine failure.

Instead of rebuilding your 2JZ, use this guide to stay ahead of the game. Because your Lexus IS300 Oil Pump requires you to remove the front half of the engine, you might also want to service your IS300 water pump as well.

Guide to Servicing the Lexus IS300 Oil Pump

Wondering just how to service your 2JZ? Good thing we’ve got the DIY articles and How To Guides to get the job done. As previously stated, it’s a good idea to inspect or service everything in front of your engine. These things include but are not limited to your Lexus crank angle sensor, distributor or timing belt.

Before you begin, our Lexus IS300 Oil Pump guide assumes you already have access to the front of your engine. Once you have access, you can begin removing the bolts that secure the 2JZ oil pump in place.

Make sure to undo these IS300 bolts in a clockwise motion. Never undo the bolt completely, and make sure to evenly distribute the load. If you are already servicing or removing your 2JZ engine, this makes this entire process much more easier.

You may or may not need to remove your oil pan for this job. What you will need to remove is your IS300 crank bolt however. This is also called the crank snout bolt, and can become stuck very easily.

Remove your Lexus IS300 Oil Pump. If you suspect that your pump is bad, you’ll need to use a feeler gauge to check IS300 oil pump clearances. These oil pump clearances will tell you whether or not you need to replace the Lexus IS300 Oil Pump.


Step 1 – Inspect your IS300 Oil Pump Rotor Lead


The rotor lead is the front edge of your interior oil pump. Your 2JZ oil pump operates by rotating these two rotors to provide positive oil pressure. In order to see if your IS300 Oil Pump is bad or not, you’ll be checking the clearances between the two tips of the rotors.

This is also called the lead rotor edge. In your 2JZ VVTI engine, you want to ensure that your factory oil pump clearance measures between 0.310–0.490 mm (0.0122–0.0193 in.).

Should you find that the clearances of your oil pump fall outside of this range, you need to junk your pump. If the 2JZ VVTI oil pump has excessive play in the rotors, or more than 0.53 mm  or 0.0209 in for your VVTI 2JZ engine, you are suffering from low oil pressure.

In an engine like the 2JZ, oil pressure is vital to proper function. Need to replace your IS300 Oil Pump? The part number for this part from Toyota is 15100-46090.

Step 2 – Check IS300 Oil Pump Body Clearance


The next part this guide will show you how to measure the clearance of the IS300 oil pump housing and the rotors. Over time the rotors may wear or the clearance of the housing may runout. Should this happen, you can experience a loss of oil pressure at the wrong time.

Like we did for the lead rotor edge measurement, the VVTI versus non-VVTI 2JZ engines have different measurements. Any IS300 with a VVTI 2JZGE engine should have a housing clearance that falls between 0.100–0.175 mm or (0.0039–0.0069 in)

Own a non-VVTI engine? The maximum range for oil pump rotor clearance is 0.20 mm (0.0079 in.)

Should your oil pump measure out of spec, it’s time to replace it.

Step 3 – Inspect 2JZ oil pump rotor trueness


Because of the heat associated with the inline six engine, these oil pump rotors can also warp. This usually causes the rotors to dig into the exterior oil pump housing. When this occurs, metal shavings can work their way into the engine block.

This will cause premature engine failure, and can easily be avoided with some simple Lexus maintenance. For this part of our Lexus IS300 Oil Pump guide, you will be using a mechanic’s straight edge.

Place your straight edge against the rotors and the housing. The measurement you are looking for here is between 0.030–0.090 mm or 0.0012–0.0035 in for those non-metric mechanics. 🙂

Should the feeler gauge slide under the edge with more than 0.12 mm or 0.0047 in clearance, the pump must be replaced.

Step 4 – Service front mail seal on your 2JZ engine


The front seal on your oil pump can become brittle over time. This can create a dreaded 2JZ front engine leak condition. To prevent this you should always service the front mail seal. Using a flat edge screwdriver, brace the housing with a rag to prevent damage.

Because the Lexus IS300 Oil Pump housing is aluminum, damage can occur. Use caution here as you flip the front main seal out of the housing. Should this fail, you can also use a large socket to punch the 2JZ front mail seal out of place.

Remember that your Lexus IS300 Oil Pump also comes with an option to have a replacement front main seal in place already.

The last part of our Lexus IS300 Oil Pump guide covers the 2JZ oil pump relief. This valve helps relieve pressure and maintain consistency in your oil pump housing.

Carefully pry away the outer seal to remove the inner valve. This valve must be checked for clear operation. You can also flush the valve by submerging the unit in thin motor oil. Take off the IS300 plug and gasket, make sure to discard of the compression ring and operate the valve under oil.

There’s also a gasket responsible for keeping debris out of your IS300 oil pump. This gasket should always be replaced when checking your Lexus IS300 oil pump. Torque the outer IS300 oil pump cap to 49 N⋅m or 500 kgf⋅cm. Again for those non-metric mechanics, you are looking for 36 ft⋅lb for a VVTI 2JZGE engine.

Assembly – Lexus IS300 oil pump guide


When buying a replacement Lexus IS300 oil pump, there should be replacement o-rings. These maintain the seal required for proper oil pump operation.

Installing these seals should be done with a high-temp gasket maker or the recommended sealant. Toyota recommends part number part number 08826–00080 for the installation of this oil pump.

Make sure to carefully lube the crank snout. Do not overlubricate the crank before installing your new Lexus IS300 oil pump. When sliding the pump over your Lexus crank, make sure not to disturb the placement of your front main seal.

Now tighten the Lexus IS300 oil pump bolts to 21 N⋅m or 15 ft⋅lb. Tighten in a counter-clockwise rotation and never over tighten one section of the oil pump housing.

Any questions about this Lexus IS300 oil pump how to? Leave us a comment below and let us know.

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