Topic: Best way to get an engine looking brand new...?

[SClay115]

Working on a relavitely snotty SOHC Honda, and I know the engine is good under all the nasty aluminum corrosion and such, I just can't seem to get that beautiful natural aluminum finish I see on some of the bikes on here. Anybody have any suggestions? Someone up here at the job suggested media blasting, thoughts?

And when I say brand new, I am pretty much referring to the one CB350 up on Ohiocaferacers.com. That thing looks pretty much like it rolled off the showroom floor, maybe even better. I'm an engine guy, and I would love to have it look perfect as such.

Steve

[jalfonso]

I'm pretty sure there's more than one way to clean the engine but glass bead blasting would give it a nice satin finish.  I plan on doing that to my 550.  Just need to make sure you tape everything off REALLY well.

Good luck.

John

[736cc]

http://www.sohc4.us/forums/index.php?topic=17081.0

[seaweb11]

do some searches on the site for engine cleaning, polishishing etc. There are 50 some odd threads on just this topic.
You will find what your looking for

[kettlesd]

The BEST way?!?!?!?!?? Oh man, are ya BEGGIN to start a war here?

The two general camps on this matter are high-temp painting vs. stripping & polishing. Both have their advantages, but believe it or not, neither way is more/less work than the other - not if you want a quality finish.

Really. Honest. Swear to god. Don't believe anyone who says you can just bust out a spraybomb and have it looking like a million bucks, or anyone who says you can mirror-polish in the time it takes to down a six-pack.

My two cents - strip & polish.

[BobbyR]

It essentially comes down to sanding the cases down past the pits and using polishing them with rouge and wheels. If the paint is bad, well you just paint to suit. The area between the fins is the toughest part. The engine on mine was all white and now it looks very nice.

[736cc]

Vapor-blast the cases if completely split apart, and thoroughly clean all galleys w/ compressed air and pipe cleaners, then paint it (paint brands discussed here in several topics). If complete motor is simply removed from frame, plug the intakes and exhausts w/ milk container caps (they're a perfect fit), clean the motor w/ EZ-OFF OVEN CLEANER, flip it over and do it again, then give it a final bath in hydroflouric acid (Mothers Chrome Wire Wheel Cleeaner). Then do up the aluminum covers by sending them out for ceramic-coating in a polished aluminum finish. Use new screws or white zinc-plate all your original screws.

[medic09]

ya can't argue with success!

I've said it before, 736cc you have GREAT LOOKING BIKES.

[scunny]

drool, slobber, drool. I love that bike

[736cc]

an occassional rat-bike crawls in...

[eldar]

Did you dig that thing up from the bottom of the harbor or something?

[kettlesd]

Im pretty sure that's his Joan of Arc special. Came out of a shop fire!

[SClay115]

Vapor-blast the cases if completely split apart, and thoroughly clean all galleys w/ compressed air and pipe cleaners, then paint it (paint brands discussed here in several topics). If complete motor is simply removed from frame, plug the intakes and exhausts w/ milk container caps (they're a perfect fit), clean the motor w/ EZ-OFF OVEN CLEANER, flip it over and do it again, then give it a final bath in hydroflouric acid (Mothers Chrome Wire Wheel Cleeaner). Then do up the aluminum covers by sending them out for ceramic-coating in a polished aluminum finish. Use new screws or white zinc-plate all your original screws.

I'll have to give this a whirl, the acid dip. I'm really focusing on the upper and lower case, and the rocker box/cover. The side panels themselves are getting polished out, and the cylinder bores/head are getting Swain coated(black, but helps with heat dissipation), so I'll let the guy doing the coating strip them how he sees fit.

I really appreciate all the responses(even though I didn't search  ). I love having useful forums around like this, so many that I'm a member on is just senseless yammering, and no real information.

Steve

[736cc]

Just don't acid dip bearing surfaces or dip split apart cases.

[Lumbee]

....my process is...

>Plug up holes
>Spary motor down with engine degresser and let sit for 15 min
>Hose down
>If you have help take to the car wash and do the above process
>Remove the valve/gear shift/stator/chain cover, strip and polish
>reinstall polished covers and tape them over
>Spary with [aluminum or black] engine paint of choice


Reinstall and enjoy!!!

[slarty-bart-farst]

I have stuck an old dishwasher in my garage.  Its so usefull for cleaning up parts. So for engine parts I just stick um in the dishwasher with loads of extra powder then jet wash them off.
Of course you could use the one in the house! Which may have been where I got the idea from, however that would make your dishes  smell of engines for a month......I guess!!
If I want to polish I sand with 400 wet n dry with the paper wet until all pit marks are gone then Solvol Autosol ( alloy/chrome polisher ) on a cloth mop on the end of my grinder until I get a mirror finish.  If I want to paint I use 250 wet n dry  then spray in "Steel Wheels" Silver.

Good luck
Graham

[SClay115]

Just don't acid dip bearing surfaces or dip split apart cases.

Why is this bad? I haven't done so yet, but that was sort of my plan...even with roller bearings? I suppose I could reinstall the trans shafts/gears and crank shaft, but wouldn't that harm the pieces?

Steve

[736cc]

I'm not a metalurgist but I believe acid etching perculates the surface and skims metal by disolving it. I don't think thats good for bearings. It does wonders as a surface prep; however it also discolors clear coat, streaks aluminum, blackens magnesium and BURNS SKIN and EYES and NOSE. Squirt it on a piece of bare alumium and it turns it white. I wear rubber gloves, work upwind, and use scotchbrite and/or 000 steel wool as an agitator for aluminum covers and lotsa soapy water rinsing. Like I said, it streaks aluminum so you want to work fast and evenly.
Of course, sending the covers out for professional ceramic coating w/ polished aluminum finish gives instant gratification

[c_kyle]

If the engine is disassembled, I would bead-blast the the case and cylinders and polish all the covers.  I won't be breaking down my engine any time soon, so I'm going to degrease the engine real good, then use scotch-brite pads and brushes to clean everything up.  I'll probably polish all the covers or have them ceramic or powder coated.

[BobbyR]

All of these suggestions have their merit and will work. The real question is to what level do you want to take the motor. 736cc has produced museum quality work. My bike is a rider so I just buff them up every couple of years to keep them fresh.

[exdrocca]

I'm kinda interested in seeing what some of you guys did that didn't take so much time/effort. I just got my motor bead blasted. It's out of the frame, but still together. I just know I don't have the patience to make it look as good as the ones that were previously posted.  I was thinking about painting it, but I don't really have a place to that is warm. Also, I have a feeling it would begin to flake off in a couple months. Anyways, just wondering what some of you did to make the engine look not that brand new.

[736cc]

I like the idea of putting it in the diswasher

[BobbyR]

I'm kinda interested in seeing what some of you guys did that didn't take so much time/effort. I just got my motor bead blasted. It's out of the frame, but still together. I just know I don't have the patience to make it look as good as the ones that were previously posted.  I was thinking about painting it, but I don't really have a place to that is warm. Also, I have a feeling it would begin to flake off in a couple months. Anyways, just wondering what some of you did to make the engine look not that brand new.

I have bum wrists and fingers from years of abuse. I use power tools instead of hand sanding and polishing. Once you have the white oxide off, you really only need to use a buffing wheel and some rouges from Sears. I would not paint the barrels since I think thet will flake off. The lower cases do not get that hot and I painted them last year with a Krylon enamel paint. Enamel is very gas proof. It is holding up very well.

[TwoTired]

I would not paint the barrels since I think thet will flake off.

You do know that Honda painted them when first built, yes?

Cheers,

[slarty-bart-farst]

736 that is one amazing looking machine.............. best picture of mine is on www.wikipedia.com enter cb750. Having now got my bike to the level its at I can see the work that has gone into yours.  What sort of mileage do you do and do you ever end riding in the wet? I am not critical of anyone that chooses to keep the bike as a show bike so please dont think I am questioning your use its just that the picture is inspiring me to go back and finish of some more odd jobs.  Bikes like this just knock people out and show just how stunning the bike is and was on launch date,  amazing.

Graham

[736cc]

I average about 7000 miles a year on my bikes (been riding 32 years now, sheesh), and ride them for all their worth, thoroughly spanking them. I avoid rainy days and puddles like the plague, and swear by S-100. Only owned 1 bike that was too nice to ride, that thing had EVERYTHING new and I cringed at the thought of gassing it up, getting carbon in the pipes, etc. Commuting the loooong way on back roads daily to work on a cherry early CB750 is one of lifes great pleasures; playing w/ the throttle and controlling the exhaust note akin to playing a musical instument. Careful regular mantainance includes detailing of dissassembled parts and occassional upgrades to a nicer original part not only benefits its appearance, but it also increases their value, adds to their safety factor AND its good personal therapy. The concept of a motorcycle constantly improving w/ age rather than deteriorating is a good thing. When its time to go for a ride or sell one of my machines, its always ready to go in its best possible condition.

Of course, the wow factor it gets when its parked at a bike hangout doesn't hurt.

[sparty]

736cc,

Now you must come over and clean the drool off my keyboard.  Damn man, how did you ever part with those bikes?  You get to see them in the calendar when you receive it.

Sparty

[736cc]

The way I look at it, finding, restoring and selling collectable motorcycles is sorta like scoring w/ many different beautiful hot women. Taking a very desirable CB750 apart, holding and massaging the parts, then riding it all the way to redline about the next best thing thing to sex

[BobbyR]

My question is where do you get the exhausts? Since they are such a prominent design feature of the bike, any restoration has to begin or end there.

[KB02]

I had an engine glass bead blasted on a kawasaki that I have. It came out looking great. The surfaces are primed for just about anything: polishing, painting, powder coating (The guy who blasted it really wanted me to get it powder coated). I just put it back in the bike as is. I really don't plan on keeping it for a very long time, but we'll see how things go with it. SO far the onoly isse that I have had with the finish is that any greasy finger that touches it leaves it mark... and it is hard to clean out.

[c_kyle]

KB02,

Can you post a close-up pic of your bead-blasted engine?

[BobbyR]

I would not paint the barrels since I think thet will flake off.

You do know that Honda painted them when first built, yes?

Cheers,

I don't think the barrels of my 78 750K were painted. The question is what did they paint them with.  I work for a Japanese Company and the frames come from Japan with a  paint that will reveal stress cracks. That is great except we can't get the paint here. We can't even bring it into the US. So we use a Dupont product for touch ups and repaints. Can you imagine what they wee using in the 1960's and 1970's. Hell, the spray Gumout today does not work as good as Simple Green on Carb varnish.

[DME]

I (and many others) have painted the barrels and head with the same paint as used on the cases.
I used Motip Engine Paint (http://www.motip.nl/?page=23&id=550) with good results.
The barrel and head does not get hot enough to destroy the paint.

Best is to use a 2 component car paint as it has the best resistance against fuel and chemicals.

Cheers
Daniel

[KB02]

KB02,
Can you post a close-up pic of your bead-blasted engine?

Not sure if I have any digital copies of the pictures (plus I just switched computers, too). I'll look and see what I can find.

[TwoTired]

I would not paint the barrels since I think thet will flake off.

You do know that Honda painted them when first built, yes?

Cheers,

I don't think the barrels of my 78 750K were painted. The question is what did they paint them with. 

Wow, you have a rare example of one that missed Honda's quality control.  Probably more valuable than a sandcast!  Imagine the ebay bidding ceiling!

Bare aluminum casting alloy is not very corrosion resistant.  I don't know what Honda used for certain.  However, given the era, I'd guess it was an oil based enamel.  Seems a bit too early for the more expensive catalyzed paints.  Lacquer had rather poor durability against the elements, particularly the Sun's rays.

Your WAY right about availability of effective products today.  Carb cleaner suffered greatly when they removed the Methyl Chloride.
The modern paint formulations aren't designed for durability or anything other than EPA concerns.  Any practical value they may have had is incidental and mostly replaced with marketing Hype.

Cheers,

[KB02]

Alright, here it goes. Ther first picture is of the engine after I removed it from the bike. Keep in mind that it is painted silver in some rattle can attempt to make it look better (The guy painted OVER the built up greese on places). The second pic is aftre I got it bacck from being blasted.

[Jim F]

check out my little picture on the left............I glass bead the entire motor as I was rebuilding it
need to keep it clean to keep it looking like that but its worth it
Jim

[loonymoon]

The work that the guys do on here is amazing. Here's a thread I started a year or two about the discolouration on the engine of my 350 - I eventually decided to do something about it. There were lots of hints and tips on the thread. Some you'll have heard before. I didn't take the engine out of the bike to tart my engine up, just used  nitro mors to get the old lacquer off, wet and dry paper, autosol and some high temp clear engine lacquer. The thread has some other suggestions as well of pics of some lovely work on some engine casings. .

http://www.sohc4.us/forums/index.php?topic=1568.0