Put in a new Denso 221-3421 radiator in a 2003 G35 Sedan. The original radiator had two L-shaped plastic brackets on the top of the radiator with captive square nuts to attach the fan shroud to. The replacement radiator has holes in the same spots, but instead of the L bracket, it is a solid block of plastic. The 10 mm bolt does not grab anything. Poking around with a thin screwdriver makes me think it is just a hole (shallower than the bolt) with no threads.

The instructions that came with the radiator are generic and don't mention special steps for attaching the shroud. I've emailed Denso, but thought this might be common knowledge for someone with more experience.

Am I supposed to drill into that block of plastic? Possibly tap it to match the bolt threads after that?

 

I have a 2005 G35 Coupe. Runs great but now over heats when at idle or in very slow traffic for a while.


Noticed that one fan was running slower than the other one. Can I replace just a single fan motor assembly or do I have to buy the entire thing with both fans? It looks to me like the fans are part of the plastic unit that attaches to the radiator.


Any ideas or suggestions will be appreciated.

 

Did you get a new rad cap too? Pressure test yours. Mine would start overheating at idle regardless of fans cuz my rad cap wouldn't seat. It was a new one too. May not even be a fan issue.

 

Yeah, I replaced the radiator cap and burped the rad and the overflow container along with opening the bleed screw up by the windshield. And I checked the fuses and relays in the fuse box next to the battery.


When the AC is on and the engine is hot and idling both fans should be on high. And they are not. One runs slow and the other not at all. Sometimes neither is turning.


HOWEVER, if I give the blades a little nudge they will begin to operate! That's why I think the fan motors are bad. I bought a set of them (2 individual fans) but it looks to me like the existing fan motors are part of the plastic outer assembly. I'll take off the air intake and the shroud tomorrow and take a closer look.


I just hope that when I get the new fan motors I'll be able to mount them...somehow...and was hoping that maybe someone had done this since these cars are now 10+ years old.


But thx for the reply.

 

Hmm..the fact that you can nudge them and get them to turn makes me feel like they may be able to just be cleaned. You may wanna take them completely apart and make sure there's not just a bunch of muck keeping them from spinning.

Otherwise if the motors ARE dead, you may be able to rebuild the shroud with the existing parts and new motors from a hardware store.

 

Thought I replied last night but it doesn't show up???


That's a good idea per the fans possibly being dirty or gummed up. I'll give that a try when I get the assembly removed.


Thx.

 

I am currently dealing with a similar issue with the Denso radiator. The brackets that are supposed to mount to the fan shroud, etc. aren't big enough. I'm not sure what's up either but will post again when I figure it out... Did you ever figure out the right part number for a Denso replacement??

 

The Sedan Radiator is Part # 221-3426
NOT 3421... that one is for the coupe. Simple mistake, but Denso's listing is slightly confusing.
DOMO

 

Do you guys have any update on this? I have an 04 sedan and looking to buy a Denso radiator replacement also. Per Denso website http://densoautoparts.com/find-my-pa...icle-selection, part# 221-3421 is for the sedan like the OP said. Hence is the Denso find my part website is wrong? I should be buying part# 221-3426, which is the listing part# for the coupe instead? thx!

 

Right... the Denso site is wrong. I had to send the parts back twice due to errors on my side then theirs. They look the same but there are brackets on the bottom that are longer in the sedan than the coupe.