The time came for my 15 year old beast's rad to corrode and bleed coolant everywhere. This replacement was pulled off (not by me) a similar year G35.

I've heard there is a "trick" to remove this bolt. It's just there is such a tight space and those damn little pins holding the nut from moving.

I have wrestled with these (deez) nuts for some time.

I have thought of 3 prepositions to remove:

1) Wedge something in the tight space (seen as between the top part of the enclosure and the top part of the nut) and attempt to ratchet it off
2) Those two little pins have something to do with it? I don't see what beyond making screwing the bolt back in easier as they hold the nut in place
3) Getting a saw and cutting the plastic sides just enough to wedge a pair of pliers and grip the nut as I use the ratchet to pull off the bolt.

I tried option 1 but the needle nose pliers that I have did not work, they kept slipping...yes I dried off the WD-40 I sprayed to loosen the rust before attempting to remove the bolt.

Frustration is moving me to option 3) but I was hoping someone knows of the "trick" of removing this?

 

I would wedge something in there and impact off the bolt and pray to the gods of Ugga dugga. Wow that's a rusty boy.

 

Yup....wedge a flathead screwdriver to hold that nut from spinning. Then loosen up the bolt.

 

Socket, breaker bar and maybe pipe handle extension, then just shear the hex head right off.

The plastic may break around the square bolt..leaving room for a hack saw blade to get in there.

or just snip the plastic with a pair of ****s (diagonal cutter), then hold the nut with a vise grip, then breaker bar the bolt head off one way or another.

 

Could also use a cold chisel and knock the head off the bolt. Definitely looks like one that should be replaced with a stainless steel fastener. Just he sure to always use anti-seize on SS stuff.

 

Thanks you for your replies guys!

Turns out cause I was holding the radiator and also attempting to wedge and ratchet the bolt off, I was not getting enough stability (quite obviously).

Always helps when you get someone actually willing to stand there for 5 minutes and hold the damn thing...

Get two things: a metal filing tool and a pair of needle nosed pliers. Bang the filling tool into the tight sight of the nut and put pressure on the pliers on the upside of the nut.
Make sure you let WD-40 sit on the rust nut overnight. Doesn't matter if you dry the top or bottom, it would actually make it harder to bang the file into the bottom space.

Have someone hold the radiator and use the sprocket end of a long wrench (to add a larger torque or moment to bolt) and twist slow. It'll come off. The less rustier bolt was easier.

 

Rusted pieces like that are a perfect situation to use Kroil Oil. This stuff is incredible. A few drops, let it sit 5-10 minutes, give it another drop or two and I haven't had a rusted bolt yet that hasn't come out. And my current project car is 65 years old!

 

I use Kroil as well, but New England bolts/nuts sometimes can't be defeated... even by Kroil.

The Kroil molecule must be a bit smaller than other similar products, because it seems to get in to places others, like say PB plaster, can't.
you can actually watch it wicking into the threads.

I also use their product Kreen on my Audi.

 

Kroil is actually not that great even though it costs a lot. Some guy on youtube tests out this kinds stuff. First place winner was using a torch to heat up the nut. Second place was liquid wrench.

Lemme see if I can find the video.

 

Here ya go!