out of curiosity, what brand of coolant will you be using? i need to do mine too.

 

The problem with not draining the block is that 50/50 mix is no longer 50/50 when mixed with remaining distilled water in the block. Will repeated drain & fill with 50-50 work? Yes, but the problem with repeated drain/fill of 50/50 mix is that you are wasting anti-freeze and you are supposed to properly dispose of drained anti-freeze, not just dump it down the drain or on the ground. So you are increasing the volume that you have to capture and haul to the recycling drop-off place.

If you have coolant in the overflow reservoir, you want to change that also.

For filling, I have one of these: Amazon.com: UView 550000 Airlift Cooling System Leak Checker and Airlock Purge Tool Kit: Automotive

Works great, no more screwing around trying to bleed air out of the system.

 

All I did was drain the radiator, then disconnected the oil cooler hose (drains the left side of block). I tried the bolt on the right side, but I didn't feel like putting a bunch of effort in trying to take it out since it wasn't moving. Also, when you drain the radiator the "overflow tank" will drain with it since it is part of the system loop. Then I filled it up with 50/50 and went on my way.

I used Zerex Asian antifreeze since it is silicate free and has phosphate, which is what the Nissan stuff has. However, I've heard they have long life blue stuff now???

 

If you don't want to remove the block drain plug, you could do the distilled water flushes, then drain the radiator and oil cooler line, then look up the capacity of the cooling system, then add half the total capacity of 100% antifreeze, then fill with distilled water. This would avoid waste of anti-freeze and excess anti-freeze disposal problem.

 

So if you drain the radiator and pull the plug in the block, is that going to get all of the old stuff out??

 

the plug drains the passenger side of the block, the oil cooler line drains the driver side of the block

 

Ok, so plug, oil cooler line, and drain the radiator and overfill, should accomplish a complete drain??

 

Yes, I think so.

 

Will the oil cooler line allow oil to flow out? Should this be timed with an oil change? What's the best way to purge air from the system when draining the block?

 

The rubber hose to the oil cooler where the oil filter connects drains one side of the coolant from the block, no oil is drained. It is convenient to change the oil at the same time, but not required. The best way to purge air is use a vacuum evacuator like an Air Lift, which is they way they recommend in the service manual. The plastic reservoir jug cap is vented, the manual says to replace with non-vented cap to evacuate air, I used plastic wrap to seal under the reservoir cap so I could pull a vacuum.

Amazon.com: UView 550000 Airlift Cooling System Leak Checker and Airlock Purge Tool Kit: Automotive

 

So are the factory oil coolers liquid/liquid? i.e. coolant flows around the oil cooler and removes heat which is then dissapated via the radiator? So when you say remove the oil cooler line your not disconecting the oiling circuit but the tube that allows coolant to flow around the oil cooler?

Any pictures of this? Would really hep to get it straight in my head.

 

So are the factory oil coolers liquid/liquid? i.e. coolant flows around the oil cooler and removes heat which is then dissapated via the radiator?

Yes, I believe the engine oil cooler uses a copper heat exchange core.

So when you say remove the oil cooler line your not disconecting the oiling circuit but the tube that allows coolant to flow around the oil cooler?

Yes, exactly.

Any pictures of this? Would really hep to get it straight in my head.

 

By the way, what is the recommended interval for replacing your radiator coolant? My weak manual doesnt even tell me that.

 

Thanks for the diagram... I had no idea the filter mount was the oil cooler. Pretty sorry excuse for a cooler, but it's better than nothing I guess. The coolant drain procedure makes much more sense now.



With GM Dexcool it's 5 years 150,000 miles. From everything I've read the Nissan coolant is simlar in makeup and has a 5 year 100,000+ mile drain interval. My truck is an '08 with just over 60k on it so I plan on flushing at the end of 2012 (if we're still alive :eyebrow: )

 

i know this is an older post. But when I work on the oil cooler to remove the coolant from the left side of the engine. Do I disconnect hose 10 or hose 3. Does it matter?

What happens if you empty the radiator and the left side but skip out on draining the right side of the engine?

 

I need to do this soon, can someone provide an answer? Thanks

 

If I drain the radiator then run the truck watching to not overheat then refill with water and run , then drain repeat a bout 2 or 3 times, then run again until NO fluid comes out will that help get the fluid cleared out of the block without taking the block plug out ?

 

The attached pdf file might be helpful for the radiator coolant change.