Painted my alternator and smog pump. Very happy with how they look, but about to put them back in the car and I read that the alternator has to ground to the engine block. I assume the paint will inhibit that. Do I need to sand the paint off of the contact points for the alternator? Thanks!

 

You might like the appearance but the paint inhibits "cooling" which is critical

 

To answer directly, yes. All the internal components are grounded to the frame of the alternator. You could probably just sand the paint off at the lower mounting bolt. I think I would sand the paint to get a good ground through the upper mounting too.

 

Thanks for letting me know. What's done is done now. I decided that if it really causes a problem a new alternator isn't THAT expensive.

 

Ok thanks. I'll do that before I put it back together. I was not aware of this when I started painting.

I'll post pics once I get it all back together.

 

What's done can be undone.
Take the alternator apart again (you DID disassemble it before you painted it, didn't you??) and have the case sand-blasted. It will look even better than it did when it was painted () AND it will cool better as well.

 

No I did not disassemble. I masked off the openings and painted.

 

if you google "painting an alternator" -- it seems like a lot of folks are doing it, but with WVZR-1 on the heat insulating effects of paint. the case halves act like heat sinks -- it's all about heat dissipation from surface radiation and convection. personally, i don't paint alternators. I'll disassemble the units, bead blast the case, and chem film the housing. I typically don't paint parts and accessories unless the general painted them from the factory. FWIW, i know several folks that have painted alternators (corvettes and those other things with wheels - ) -- can't say anyone has had issues, but never really followed up on these things. i have read several articles on thermal dissipating paint for electric motors, and it seems there are several factors that come into play - paint thickness, and color. minimum paint thickness and black is best. although, i don't recommend it, what's done is done, but if i were to paint an alternator, i'd keep the paint thickness down to an absolute minimum.

 

Thanks, yeah I put on a couple thin coats and was careful to mask off the holes so as not to get paint inside of it. I agree there could be thermal issues, but on the flip side, as you said, lots of people do it and it doesn't seem to be a problem for them. I'd love to polish it up, but I don't know that I have that kind of time :P

 

What about all the chrome alternators I've seen? I would think chrome plating is far thicker than a couple coats of paint...

 

From lots of googling as well as forum replies, the impression I'm getting is that paint/chrome/powder coating is worse than bare metal for the alternator because it acts as an insulator. HOWEVER, for normal day-to-day driving it probably doesn't matter enough to cause you an issue. I'll let you know once I get her back together. I did make sure to sand all the paint off the contact points so the alternator can connect to the engine block and ground.

 

Thought I ought to post a pic of the engine bay since I've painted. I think it's looking pretty good.

SIDE NOTE: while I've got the injectors and runners off, I wanted to clean up the top of the manifold, but of course there are large gaping holes that go into the cylinders that I don't want to get water into. Anyone have a solution that doesn't require me to take the manifold off? I'd rather not do that if I can avoid it.

 

Wow! Looks good! I've only been following your threads off and on but it seems that all the work is starting to pay off.

 

Thanks man! There are some days where I feel like I'm wasting my time, but then it starts to come together and I remember that I'm enjoying this Good to know I'm not the only one who thinks it's starting to come together!

 

I don't have the solution you want, but I would definitely go ahead and take it off since you've made the rest of the engine look good. I did mine last year and couldn't be happier with the results. I used a $7 bottle of Eagle One Wheel and Tire cleaner and a hard bristle brush, it cleaned the manifold right up. You're only about 15 bolts and a coolant drain away.

 

Do you have a detailed writeup of how to go about doing that? I've got the Eagle One already and I completely agree I'd like to get the whole thing looking sparkly since I've already got it all apart.

 

Do you have an FSM? Makes life easy!

From the photo you posted and from memory, you'll need to do the following:

1) Start draining coolant, there's a valve on the bottom of the radiator, passenger side. I can reach it by wrapping my arm under the frame in front of the tire.
2) Loosen both fuel lines at the front of the fuel rail and remove the two bolts there (they look like they're gone already).
3) Remove the 4 bolts from the fuel rail (also look like they're out already).
4) Carefully lift the fuel rail up, I pried very carefully on the fuel injectors since they were all being swapped out.
5) Remove the two bolts from the coolant tube on the top of the manifold. At this point I would just remove the hose and paint the tube a nice color.
7) I used a wet shop vac to get as much coolant out of the intake manifold as I could at this point.
8) Unhook the two electrical connectors from the sensors on the front of the manifold if not already done.
9) Remove the coolant hose from the front of the intake manifold.
10) The base of the distributor should be plain as day right now. Wipe it clean and mark it against the intake manifold. I marked mine at the very front edge of the distributor, center of the manifold. That way when I inevitably clean off the mark on the manifold I can still get within a degree or two. Also remove the cap and mark the rotor against the distributor. You need these for when you put it back together.
11) Remove the hold down bolt for the distributor and unhook all connectors. Pull the distributor out.
12) At this point you should have 12 bolts to yank and then the manifold will come off.

I believe that's everything, but someone please chime in if I missed something.

A couple of other notes:
- Check around for the throttle body bypass. Instead of having coolant run through the TB, I opted to run a coolant line from the front of the manifold over to the heater line, bypassing the TB altogether. It gives you a side benefit of making future removal extremely easy and not messy.
- When you put the distributor back in, you'll want all of your marks to line up. The initial insertion of the distributor will be about 20 degrees off from the mark - that's because of a helical gear. When you remove the distributor, watch the rotor spin slightly and you'll see what I mean. You might also need a long flat head screw driver to spin the gear inside the motor that the distributor sits in.

It may or may not sound daunting, but it's a relatively easy procedure and if you take your time it'll make everything look great. It's also a great way to learn more about your car!

 

Whoa-that's a really good writeup. That sounds like something I can do. I was a bit daunted about the distributor having to come off. There's not a gasket or anything?

 

Because of a faulty aftermarket intake manifold I ended up throwing out, I had that thing apart three times inside of a week. I got pretty good at stripping it down. :-)

There's a small paper-like round gasket under the distributor. It doesn't really need to be properly seated or anything, just "there" when you put it back together. If you already have the $30 intake manifold gasket set for the plenum stuff, you'll find it in that bunch.

When you take the manifold off, do a good job of cleaning the surfaces. If you need the torque sequences and whatnot let me know and I'll grab them.

 

Also, I said "coolant tube" a couple of times. That's the thermostat housing. It kept bugging me that I couldn't think of the name of it. :-P