It seems I'm having trouble keeping some of the bolts from surface rusting after painting them.
I'm talking about painted bolts in the engine compartment ?
Maybe clear coat ?

Yeah, maybe like a satin finish polyurethane so it doesn't shine too much.

Do you drive yours in the rain a lot or park it outside? I live on the coast about 1/3 mile from the water so the air is a bit on the "salty" side. Mine seem to be just fine with the Hirch paint only. 3 years now...mind you the only water it sees is the odd time I take it to the coin wash to get the bugs off the front...

The only water it sees is when I wash it.

Doug,

Clear coat will help. I've been having good luck lately having all of my hardware "clear zinc" coated and then paint them for the correct-appearing finish.

First you have to have someone media blast the hardware with glass bead, then take them to a plating company and have them "clear zinc" coated. It's a wet process that has replaced silver cad plating.

There are a ton of platers in Michigan. I use one in Flint just a few miles from the house. He does "government jobs" on the side. A coffee can full of fasteners usually runs about fifty bucks.

When you refinish your hardware are you getting all of the rust off before painting?

Zinc chromate primer perhaps?

How are you having rust issues if you dont drive in rain and from a painted bolt?

Why don't you just replace the old bolts with new ones? I think there are only a few actual oddball pieces, the rest is just standard hardware.

Tape'm off and give'm a shot of clear from a rattle can.

You could black anodize them. That will hold up under any conition.

I did not know that Doug's bolts were made of Aluminum.

Factory bolts were Cadmium plated to resist corrosion (rusting). Cad plating is a big "No-No" these days, but you CAN still buy bolts with Cad plate if you know where to get them and you don't mind paying through the nose.

Doug - are these the bolts on your water pump?

I take it you can only anodize aluminum

Yup.

Use stainless steel bolts or plated grade 8's and paint them. Thats how I did the engine in my jeep and it looks like the day I put it in 3 years later.

Stainless steel that contacts Aluminum will corrode. It's not the same color as rust, but they lose their nice bright color and grow this gray-ish looking stuff if they are in direct contact with Aluminum, like an aftermarket intake manifold.

Sounds like marraige...

The bolts at each end of the fenders I painted silver along with the bolts that come up thru the inners fenders I painted the threads and the nuts silver.
They are the original bolts that I sandblasted primed then painted.
I did this about 2-3 yrs. ago and since the motor is out again I figure I mught as well redo the engine compartment.

You could send them out to get a black phosphate coating. May be a little expensive though. I throw hardware in when we send parts out for coating at work. Can't beat the price!

Would por15 + a finish coat work?

So those nice shiney ss bolts that I used to install my aluminum radiator should be replaced? What about zinc coated grade 8's?

i used eastwood rust converter on some of my bolts that had surface rust. it removed the rust and turns metal a black tint.

Depending on what finish the fasteners 'should' have, for originality, you could de-rust them and simply satin clear coat (for natural steel look), paint them with 'cast blast' or similar paint for more of a factory natural look or buy one of Eastwood's (ot others)plating systems that offer a black phosphate which many underhood and underbody fasteners came in.

You'll need to let whatever paint finish you apply dry really well (several days) and then be very careful when re-installing not to remove the finish on the corners or edges.

grant

Thanks The reason I pained the bolts silver is because my car is black with a black engine compartment.