Painting the engine

Recieved my XJ CD's there last week and am now finalizing my wish list from Chacal, so I am finally getting around to start the rebuild of my maxim x.
I was wondering about the painting the engine. The paint that is on it now is not too bad but has some flaking spots and I would like to freshen it up with some nice gloss black. Is it better for me to remove the paint that is on the engine now or should I paint right over it. If it is better for me to remove the old paint what would be the best way to do that. I am pretty mechanically inclinded but not wise to the ways of paint and body work. Any help or pointers would be appriciated. Thanks.

 

Depends on how nice you want it to look when you're done.

If you want it to look NICE, then the old paint comes off, usually either with stripper, or glass-bead or walnut-shell blasting. Either of those methods basically will require you to remove the engine from the frame, unless you're anal-retentive beyond belief in masking procedures......

Luckily removing the engine from a 700 model isn't all that ba, as the right side frame tube un-bolts fromt he rest of the frame, making engine removal not "easy", but at least a whole bunch easier than on any other bike............

 

And once you get it out, if you want to do a really nice job, you'll take a bunch of the parts off (like the water pump and coolant piping) so you can get the old paint off everything.
Which means you'll need to buy a bunch of O-rings and some gaskets from Chacal!

While it's out, it a WHOLE lot easier to check your valve clearances too....yep, buy a valve cover gasket from him too
(no commission required Chacal) LOL

 

New user here, just got a 82 550 that I'm in the middle of a rebuild on and I had flaking paint coming off of two parts of my engine, at the valve covers and part of the middle of the engine beneath where the head bolts to. I just so happen to be at Sears, and they had some pretty good BBQ grill paint on sale. I picked up a can with the intention of repainting the flaking areas. The nice thing about BBQ paint is that it's rated for high temp (I think up to something like 1100 degrees), so I was pretty sure that the heat from my engine wouldn't kill this stuff right away.

I got home, cleaned the areas up with a wire brush, and masked the rest of my engine. I shot both the valve covers and the engine. It looks great, honestly, and I didn't have to remove my engine from the chassis. I'll post pics a bit later if I can, but it was a cheap, effective way to make it look good.

Now if only I can get the electrical straight and stop my carbs from flooding. *sigh*

Should be a fun day..

Just my thoughts on it.

~Edit~

The BBQ paint is flat black. Not very shiney, but it still looks pretty damn good considering it took me all of 1/2 an hour. I'll be sure to get some pics up....

 

One thing you might want to think about is fuel resistance....

Very few paints, and, as I found out recently, not all powdercoats, are fuel resistant. If you ever have a carb overflow, or leak some fuel when disconnecting the carbs, your nice paint job may quickly wash away.

Clear coats will seal the paint and leave it fuel-proof, but I don't know how many of them are suitable for the temperatures of an engine.

What I did find with my recent powdercoating experience was that, while the gloss black powdercoat did soften when touched by gasoline, it didn't just wash off like the engine paint did. So powdercoat, at least, would offer some level of survivability in case of a gas spill. On the other hand, powdercoat means disassembling the engine, not just removing it.

If you do happen to find some fuel-resistant, single component, hi-temp paint, please let us know. I do know that model chemical companies, like Sig, make fuel-proof colored dope, that I suppose could be sprayed on, but again, there's the temperature resistance question.

------Edit------

After checking around a bit, I did find one company, Moeller, that makes oil and gas resistant engine paints. They run about $15 a spray can, but, might well be the way to go.

 

Ah, true about the paint mixing with fuel, forgot about that in my rush to make it look decent. And I should know better, as I just got done shooting my tank.

Which actually brings me to a question. How resistant is your automotive-grade clearcoat to fuel? I shot my tank and side covers with all DuPont enamel primer, paint, and clear. . It's been painted for about a week, and I'm at the point where I'm troubleshooting the carbs, so I'm (hopefully) getting pretty damned close to done. I was wondering if I should wax the clear to add another protective coat other then the clear. I'm pretty worried that I'll end up spilling fuel on it (and I've seen what fuel can do to paint) even though the guys at the paint store said it wouldn't be a problem.

Any suggestions?

 

Normally it is the clear coat that is fuel resistant, and it is also the clear coat that allows the paint to fully cure and harden.....most people don't realize this. The chemical reaction between the paint and the proper, COMPATIBLE clear coat is what "cures" the paint.

And most clear-coats can take quite a long time before they actually fully harden and cure themselves. They may become "dry" to the touch in 15 minutes or 12 hours, or whatever the label says, but for the clear to actually fully harden and dry---which is when the chemical resistance takes effect....can take up to 30 days!

Which means you should wax it for at least that time. Wax will interfere with that process.

And wax, being fuel-soluable, won't protect against fuel spills.

If you stick your nose right up to a recently painted part, and take a good sniff, you can "smell" the paint........but what you're really smelling is the solvents in the paint evaporating (and that evaporation of the solvents is what allows the paint to "cure". Once the solvents are fully gone, the paint is cured).

If you can smell those solvents, the paint or clear coat isn't cured!

There are high-temp clear coats available.

 

POR-15 makes an engine enamel that will stand up to gasoline.
Lookie here. I think the only thing that will easily take it off is their own solvent. It's not a rattle-can product though...

 

Once you get away from spray cans, then you're in a whole 'nother world, as the catalysts and hardeners and etc. can be added to the paint or clear-coatings, and it is those additional elements that serve to really "toughen up" a coating.........

But then you get into the whole other world of having the proper spray equipment, the proper settings for that equipment, etc. etc.

The average, at-home, inexperienced person (inexperienced with spray gun equipment and techniques) can do a better job with spray cans as long as proper pre-paint methods and techniques are followed (because a great "paint job" really means a "great pre-paint preparation of the surfaces to be painted") than they can do with spray-gun equipment.....that's why my experience has shown.

Your results may vary!

 

halfords (uk) sell cans of fuel resistant engine paint in flat black, gloss black red and silver. its good stuff, i've use flat black and gloss red on a few engines and it has always done the job. I did a lovely ford V8 all black with gloss red cam covers, that got shed loads of fuel spilt on it when the carbs exploded, the paint stayed good though.