DIY: Video: Engine Coolant Replacement
Upper Radiator Hose (21501-1NA0A)
Lower Radiator Hose (21503-1NA0A)
so my upper radiator hose is seeping & plan on changing it + refilling the coolant.
what's the chance that my lower radiator hose will seep too? i need to change that too? might as well? + if i need to change the lower radiator hose, i will need to burp the system again? mannn..
i think i might have answer my own question there...hahah 
upper hose looks easy to change. is the lower hose easy as well?
yes, parts are definitely cheaper at nissan dealership.. part w/ part number is a big help!! thanks a bunch
Lower Radiator Hose (21503-1NA0A)
so my upper radiator hose is seeping & plan on changing it + refilling the coolant.
what's the chance that my lower radiator hose will seep too? i need to change that too? might as well? + if i need to change the lower radiator hose, i will need to burp the system again? mannn..
i think i might have answer my own question there...hahah 
upper hose looks easy to change. is the lower hose easy as well?
yes, parts are definitely cheaper at nissan dealership.. part w/ part number is a big help!! thanks a bunch
Last edited by tite_tite; Sep 19, 2015 at 08:25 PM.
watching the video again, i just realize he mentioned the size of the hose to assist w/ the draining. 5/8 ; 16mm
was able to get it @ advanced auto parts. it is in a spool so you can get it by the inch/feet.
pic is 7 inch & it worked good

NOTE: lower drain, hose works good. upper bleed, it is a little tight so you may have to work it in & make it ghetto-fabulous
or get 1 size biggerthanks all for your input
Did mine today w/ the Lisle Funnel kit, worked great and thanks for the tip OP about squeezing the upper radiator hose, then inserting that long t-plug to pull the funnel off and keeping the radiator level just below the cap. So much cleaner that way!
And from my measurements I drained 1.5 gallons (including dumping my reservoir tank), then filled the same amount in, seems to be almost exactly the level it was prior.
And my heater hose didn't have a air cap/bleeder either.
And from my measurements I drained 1.5 gallons (including dumping my reservoir tank), then filled the same amount in, seems to be almost exactly the level it was prior.
And my heater hose didn't have a air cap/bleeder either.
Just did this, thank you for the extremely helpful video. I used a regular funnel but it spilled just a little bit out of the radiator bleeder hole(didn't have a pipe) and also some overflow from the radiator cap as well, but I just doused the area with some water to hopefully get coolant off of the hoses.
Also, since in have an 07 I had the air valve. Not sure why Infiniti decided to make the car much harder to service after the switch to the G37 nameplate. My buddies G37 coupe has no transmission dipstick, so its a huge PITA to pump fluid in instead of using a funnel, and also doesn't have the bleeder valve.
Also, since in have an 07 I had the air valve. Not sure why Infiniti decided to make the car much harder to service after the switch to the G37 nameplate. My buddies G37 coupe has no transmission dipstick, so its a huge PITA to pump fluid in instead of using a funnel, and also doesn't have the bleeder valve.
I am planning on doing the coolant flush soon and had a few questions. The car has the blue coolant which comes in 50/50 premix in gallons so should I buy more than a gallon or should it be enough? What do you recommend to use to check the freezing point, a refractor or just a regular coolant tester? Thanxs in advance.
Thread Starter
Joined: May 2005
Posts: 401
Likes: 49
From: Bay Area, CA
I am planning on doing the coolant flush soon and had a few questions. The car has the blue coolant which comes in 50/50 premix in gallons so should I buy more than a gallon or should it be enough? What do you recommend to use to check the freezing point, a refractor or just a regular coolant tester? Thanxs in advance.
I’ve never seen blue formulas available in concentrate form although it’s possible they do exist. My recommendation is to purchase the genuine nissan coolant. You will need 2 gallons.
https://www.ebay.com/itm/OEM-Concent...item237d569ce9
Looks like some Pep Boys may have this in stock.
Looks like some Pep Boys may have this in stock.
Joined: Oct 2011
Posts: 6,103
Likes: 592
From: People's Republic of IL
I'd say having the front lower than the rear is better than the other way around.
Are you removing a hose to drain or unscrewing the petcock? If the latter, probably a good idea to have a new oring to replace with when reinstalling.
Are you removing a hose to drain or unscrewing the petcock? If the latter, probably a good idea to have a new oring to replace with when reinstalling.
You can but I had to use a stubby screw driver. Also, don't forget to open the purge valve up top on driver's side. When pouring the new coolant in, do so at a very slow pace as to avoid getting air in the system. I've read about some people needing special pumps and tools but just pour a bit in, wait for bubbles to escape and fluid to drop then pour a bit more in. Slow and steady. Also, don't forget to have someone give the car some revs to open the thermostat. Feel that bottom hose and you will DEFINITELY know when it's opened.
Did the coolant change nice and smoothly. I'm kind of worried now though. I purchased genuine Nissan long life Blue coolant. And my old coolant looked quite blue, but after a few hours it looks green. Is it okay if I used blue coolant instead of green? I heard they are pretty similar. Or should I go ahead and change it out?








