Rusted coolant bypass pipes
 

Rusted inside out. OK cheap metal OK. Not interested in the OEM on this one.
Wondering what other Max owners have done about the rust build up from these pipes?

I don't know how yours got rusted. Mine are in great shape. Rust is due to coolant is not be properly replace since the chemical in coolant have a limited life span due to head and cooling and they do break down into corrosive acid if they are not being changed regularly approximately 5 years or 60k miles. a lot of people neglect to do it and end up with a corroded radiator or metal pitting inside the block.

The radiator it was real bad and leaky! Here's the inside of the pipe.
https://cimg7.ibsrv.net/gimg/maxima....41b0bb8790.jpg

I had to do this last summer as well! I went OEM from Nissan Parts Zone, I think they were like 80 or something for both pipes. I did it while replacing the spark plugs and rear valve cover gasket, so it made things a little easier. I've actually had to replace a lot of the coolant lines on this engine, but rust is par for the course here in Philly!

Even though the insides of the front coolant pipes on my car were not rusty, the outside was. So i went to pull a part and got a replacement from another rust free car.

Previous owner was from rust belt PA.

I've never seen a radiator so badly corroded until I bought this car! Nissan swapped it out with value advantage and it's already showing signs of corrosion.

What about just cutting off the pipe and leaving a nipple and clamping some 3/4" hoses to it?

The fact that the inside of the pipe has crud in it and the radiator was plugged means that the previous owner did not maintain the cooling system. A cooling system that has good antifreeze in it will not develop that crud. They probably were running plain water in there for a long period of time.

What it looks like is the previous owner hit something real hard crushed the cross member then also damaged the radiator in the process. It appears that way then never addressed the issue with the insurance company.

I'm realizing that it may Also be K-Seal not just rust!
That's what I think that a previous owner loaded a bottle or two of K-Seal which left deposits that resemble corrosion in It!

My coolant bypass tubes are pretty crusty on the outside. Once they start leaking, I'll put some JB-Weld on them until I decide to replace them.

I had pitting and beginning to think the green coolant they had running through it had harmful additives like borates/phosphates in it that played a role.
They sell the green as any make/model but it could contain the same things that the blue doesnt.

Also have a look at the water pipes in and out of the oil cooler.
Mine rusted through recently and I had to do a late night repair to just get to work next day. Replaced the outlet pipe with a length of water hose, then sent the car to the shop to do the same on the inlet pipe.

Don't think there is one on the 3.0
That may only be the 3.5​​​​​​

Does it rust from the inside? Or just the outside?



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Those lucky owners of 3.0! :)
Rusts from outside. :(

Like I mentioned the rusting on the inside is pitting. This may be from not flushing the radiator once/year or from using coolant loaded with silicates/nitrates