Hi there, I am replacing my stock radiator with a new aluminum radiator.

There seems to be a problem with attaching the steel side brackets to the new radiator, the two different metals have an electrolytic reaction causing the aluminum to oxidize and corrode.

In my manual it states to use a zinc-chromate washer between the two metals to prevent the reaction.

I had an aluminum sill plate dissolve on another car, always wondered what caused it!

The side brackets will be painted and I also will spray some clear satin on the radiator to slow down the normal oxidation that occurs over time.

Do you think the paint will provide the barrier needed to prevent the reaction?

Let me know what you think.

 

On the fd, the aluminum door sills come with a plastic washer that goes between the head of the screw and the sill for this reason. Would advise doing the same. You can buy nylon/Teflon washers and try

 

Thanks for the reply, I found the zinc-chromate washers in the size I need. I thought that they would be a difficult item to find, but I guess not.

I might try putting a thin plastic washer between the bracket and the radiator, then use the washers I ordered under the nut and bolthead. This should do the trick and is worth the effort.

One thing less to be concerned about!

 

I would also use some anti-seize. Not on something like the door sills where it would be messy, but on the radiator mounts it should be fine. I use it on literally every fastener in the car other than the interior.

 

That is my game plan, I have three different anti-seize lubricants.
Regular, copper, and nickel!
For this problem I will be using the regular.
The nickel will be used on the exhaust system.
The copper will be used on all the grounds!

I did not use any on the last replacement engine,and now when I needed to take it to pieces for this new engine I had a lot of frozen fasteners and snapped bolts!

 

I tend to use the regular aluminum stuff on everything (except grounds). It does work on exhaust fasteners but gets kind of gummy from the heat. The copper is better at withstanding the heat but I find it doesn't work as well as aluminum in terms of anti-seize properties. I've never used the nickel stuff though, so I'll have to give it a try! A little extra time chasing threads and using anti-seize now saves a lot of time and frustration later.

I usually use dielectric grease on the grounds. Then again anti-seize is just dielectric grease with metal dust suspended in it, so I don't think it would make much of a difference other than dielectric being cheaper at the parts store

 

in the future, you can find isolators in your recycling bin, theyre usually in the form of plastic milk containers or other fluid containers. cut them to the size you need and toss the rest back into recycling. no need to go to the hardware store or buy fancy speciality washers.


just had to go through this with the rear shocks on my hybrid vehicle.

 

For the novice DIY people, dielectric grease is NON-conductive! when it is used on an electroactive connector it separates the connectors so there is no current crossover.

The electrical path is from the metal to metal contact in the connector itself. So, use contact cleaner on both connectors before applying the dielectric grease!

If I am mistaken in this post please let me know. A little knowledge is a dangerous thing!

 

From what I understand, anti seize on hot fasteners like exhaust works by leaving the soft metal powder in the threads after the grease boils/burns off. The soft metal then acts like a dry lubricant upon removal.

I use it religiously also, I always thank my past self when I have to work on the car again.

 

Great idea, I have some mylar sheets somewhere, cut it to size and superglue it to the brackets where they bolt to the radiator. Thanks!