[Advise Needed] Correct way to finish off Stator + Clutch Cover and Cylinder Head

[Agemax]

Sure you can. It takes effort. I've done valve covers lots of times. Most people just don't want to devote the time. Seems like a lot of people are looking for a quick fix, but in reality, patience and persistence are all that's needed. The head/cylinders/block are a different subject. If you're going to repaint them, even sanding those parts as much as you can is safer IMO then blasting. Getting parts clean is the key.

for a perfect finish, or a key finish for painting it is impossible to do the head or block by hand. blasting is the ONLY way as long as they are washed properly after.
you mention a quick fix! sanding all the cooling fins is a quick fix and will never be as good as blasting.spend the time masking up the key areas and get them blasted and you will get a better finish than you ever will with sanding inbetween cooling fins!
show us some pics of your hand finished head/block handywork

[nvr2old]

Here's an XL250 Honda that I did, before and after. All sanding.





Here's my GS1000S engine right before painting it and then all done. Lots of sanding and cleaning, but no blasting. The valve cover is finished in 600, every nook and cranny, and it could just as easily been taken to 1500 and polished. Same for all the covers. A paint stick wrapped in sand paper makes short work of doing in between fins.

[nvr2old]

Here's an example of a cleaned, sanded, and hand polished engine with no sand blasting. Not saying blasting's better or worse. Just saying it can be done very well w/o blasting. Results will vary either way. It's how much you want to invest, time or money. I got a lot of time in these, but almost zero cost other than paints and polishes.

[duaneage]

Soda blast

I used a small tank style sand blaster but loaded it with baking soda.That's the same sodium bicarbonate used to brush teeth, cook, clean and deodorize the fridge. I bought 50 pounds of baking soda for 58 dollars. I used about 30 pounds to clean all the old paint, corrosion, and grease off my 400 yamaha engine. The finish was perfect. And when you are done just hose it off and then dry the engine with air or a leaf blower.

I plugged all the holes but even if it gets in the engine the baking soda just dissolves. It doesn't harm you or the environment, you can even eat it. When done put a hose on the driveway and it disappears.

Just don't do it on the grass, the baking soda will kill the grass by making the soil too alkali. If you do get a pile on the grass and it turns brown just dig it up and use new dirt and seed.

I have some pictures somewhere of the results, I'll try and dig them up..

[joshes]

Hi NVR2OLD and all other members who have contributed to the thread,

First of all thank you for all the useful inputs - as well as awesome pics! Man, I envy you guys in the US and UK! The limitation of doing so is high in Jakarta. However, the good news is that manual labour is cheap - I can have as many people I want to scrub the parts.

However, I still have a (possibly silly) question. Did you (any of you guys) take apart the engine when you polished them? As the engine I have now works fine (well it sounds fine though) - and I am contemplating to take apart the engine in order to polish the parts.

It would be silly if, for the sake of cleaning the outer parts of the engine - I have to take apart the engine and once it is put back together, the engine does not run as well as before. I would bang my head to the wall! I don't want the cosmetic works to be detrimental to the running of the engine.

The least I am planning to do is to take off the engine from the frame (like NVR2OLD) put it on a stand.

I am not a mechanic, although I have a friend who is a savvy mechanic. He is happy to help undone the engine from the frame, but he is also unsure if taking apart the engine is such a good idea.

Any thoughts on this?

Thank you all for the useful inputs!

[duaneage]

I soda blasted the engine while assembled. I didn't need or want to rebuild the motor, it was all cosmetics.

[joshes]

Hi Duaneage,

Many thanks for the insights. I am interesting with the baking soda method. Can you kindly explain in details as I am now persuading my local sand blaster to change the sand beads with the baking soda. So you do not need to blast it in the 'sandblast chamber' which means it is done outside.

What sort of protection (protector outfit) that I need to be concerned with?

Can you enlighten me with some information?
Thanks a lot buddy!

[duaneage]

Hi Duaneage,

Many thanks for the insights. I am interesting with the baking soda method. Can you kindly explain in details as I am now persuading my local sand blaster to change the sand beads with the baking soda. So you do not need to blast it in the 'sandblast chamber' which means it is done outside.

What sort of protection (protector outfit) that I need to be concerned with?

Can you enlighten me with some information?
Thanks a lot buddy!

Sure.

Aramex is an international company that sells blasting grade baking soda They offer two formula here,120/180 grit and a rougher 80/120. I used the 120/180 stuff.You could use the baking soda sold for cooking but it's not consistent like blasting grade.

The air has to go through a dryer. The dryer removes moisture from the air that can cause clumps to form and clog the sprayer. I started with about 15 pounds of baking soda to the tank and ran 80 pounds of air on it. The tank I have pressurizes the media (baking soda) and pushes it down where another stream of air goes past and sends it to the nozzle. You adjust for a usable stream and keep adjusting the pressures as the media goes down. An experienced sandblaster should know how to do this.

Test the blast on the bottom of the engine first to get a feel for the pressure required. I did clean off much of the muck and grease to make it easier. The baking soda will soak into the grease and you will be able to take it off with a fingernail.

Protective gear is similar to any blasting setup, Gloves, long sleeves and a hood. If done outside with a breeze you probably don't need a respirator, baking soda is harmless stuff, but heavy clouds should be avoided. Again, grass or plants shouldn't be bathed in the stuff. Cleanup is a compressed air nozzle, hose and brush. The Baking soda on the ground can be simply washed away, no need to recycle it.

Baking soda will not remove rust from metal but it does a great job removing paint and that white corrosion from aluminum while leaving a neutral finish which can be further polished. This is a good first step towards the polishing process. It will find it's way into things so plug off holes really well. Leave the plugs in and cork off the ports. But it dissolves in oil or water so it's not a big deal if it makes it into the engine.

Baking soda works by hitting the engine at high speed were the crystals shatter and remove the contaminants. All other media is hard and does not break down. This is the only environmentally friendly way to blast that does not require respirators and a big cleanup project, although respirators are always a good idea and you will have to hose down the driveway.

[Nessism]

Before blasting an assembled engine you need to plug all the openings where the media can get inside. Soda is most likely less of a problem but I'd be concern anyway if any of the grit got inside my engine.

Regarding polishing the engine covers, the factory finish is pretty close to 600 grit. Those guys recommending anything higher are going for a mirror finish, not the factory look which is actually a "brushed" finish.

These engine covers were polished with 600 and then aluminum polish.

[duaneage]

The final swipe on the covers leaves a fine series of lines in a straight line. I got the same look by using 000 steel wool. I would describe the results as a satin finish. For clear coat I de-greased the part with lacquer thinner, dry and immediately painted with clear engine paint. I gave another coat 10 minutes later. This should hold up for a few years. The leading edge of the engine in the breeze takes hits from dirt so it may develop pits and have to be redone eventually. After about 4 years and 14,000 miles my stator cover needs another polish job because of debris hitting the cover.

I used rubber balls on the ports, ran bolts into any hole I saw, and put rubber hose on the PCV port on top of the cam cover. This kept all the soda out of the engine.

[reddirtrider]

Got it!

Going back on the vapour blasting - have you heard of bead blasting. Any comments on this. The only reason for asking is that there is a limited 'blasting' options in where I live. So, just to make sure i choose the right method.

Thanks a lot mate!

If you bead blast aluminum you will get a dull finish that will need to be sanded with progressily finer paper, then polished in order to get a shine. The same is true for sandblasting except it leaves a coarser finish on aluminum than does bead blasting.

Bead blasting will work fine on non-polished surfaces such as your block. You should have the motor disassembled for this to be properly done.