cleaning, polishing and painting (with clear) an engine

[Stigy]

Hi. I'm restoring my '79 GS 550D.
I striped down my engine. The head and cylinder are off. The first thing I done was soda blasting everything roughly.
My goal is to restore the look of original GS engine. It's not necessary to give it a mirror finish.
I'm asking for advice in two subjects:
1. CLEANING: the cylinder and head will be glass blasted. But i'm wondering about the rest - crankcase especially - its oxidized at the front. It could be tricky to glass blast the entire engine. So I was wondering - is it possible to do it right with some brass/copper brush (on the driller), chemicals, polishing or any other stuff ?

2. PAINTING: Original parts are coated with silver paint or/and clear varnish. Witch parts should I paint and how, with what ? Should I use clear on everything (excluding head and cylinder do to excessive heat) ? Which parts could/should I paint with silver paint first ? Do you recommend any specific paint, clear for the job ? Is it possible to do it well with a spay paint ?

Thanks for help

 

[Stigy]

Nobody knows how to to that ?
Another thing. I was wondering -if cylinder and head are originally painted/coated ?

 

[chuck hahn]

Glass beads can get caught in oil passages so I never use them. first I get some old tooth brushes, a parts washer brush, a big jug of degreaser and start scrubbing all the crud off. I stuff the head intake and exhaust ports full of red shop rags and then gorrilla tape them shut to keep water out when power washing the engine down. Once power washed it gets saturated top to bottom in paint stripper...power wash again and spot treat any left over paint.

I paint it all with VHT UNIVERSAL ALUMINUM..part number SP-127.

https://www.thegsresources.com/_forum/showthread.php?248066-Blue-78-1000C-project

 

[chuck hahn]

Some of my engine clean up pics.

After some serious degreaser action. Took me around 3 or 4 hours to get the engine acceptable to be paint stripped.

Some SP-127 pics. Cure with several short heat cycles when you restart the bike. IDLE it for 5 or 10 minutes to get it heated up..but not long enough the paint blisters...and shut off. Let it cool and do it again b ut add more time. Rpeat the heat cool cycles 4 or 5 times and each time add another 5 or 10 minutes ( with a fan blowing on the engine ) and thuis will cure the paint nicely

 

[Stigy]

Thanks for reply Chuck Hahn.

I'm familiar with VHT products. Your "engine cleaning" tutorial is spot on. I've handled with most of paint and dirt with soda blasting. Took me 1-2 hours to "clean" it roughly.
There are two more things I'd like to ask/mention:
1. Have You used VHT Primer before the paint ?
2. I'm considering leaving the cylinder and the head without any coating after glass blasting (I've already done that - I'll make sure I'll clean them precisely). Does this make sense ? As far as i know air cooled engine should have as thin coating on cylinder/heads as possible. Sometimes they are not painted at all. VHT makes special paint for cylinders - http://www.vhtpaint.com/motorsport/vht-barrel-spray-paint
I found other similar products also - paints with perfect heat dispersive properties. To sum up: Is it a good idea to leave cylinder and head without any coating ? How was it made originally (painted or raw aluminum) ?

 

[chuck hahn]

They will eventually corrode and get discolored without some sort of paint or high heat clear I would think.

 

[Stigy]

Chuck Hahn - and what about a primer ? Have You used it before base color ?
I might clear coat the head and cylinder. But I haven't found a good enough clear yet.
The VHT flame proof clear is not resistant for fuel, oils etc. - it strips right away after contact with any of those kind of liquids.
The VHT Engine Enamel clear become yellowish after a few heat cycles.
Does anybody know of a good, trustworthy clear to be used on cylinder and head ?

 

[chuck hahn]

Never primed any..just painted and they are ok still.

 

[Stigy]

Any info about clear anybody ?

 

[nvr2old]

In 40 years of painting engines, I have never seen a heat resistant clear. Better off just using a good VHT silver and being satisfied.

 

[Stigy]

Nvr2old - Have You seen any new/stock/original engines without any paint on the cylinders ? Or does manufacturers always paint cylinders/heads with some kind of silver or black paint ?

 

[nvr2old]

I've never seen a Japanese engine that didn't have paint on the head and cylinders. I can't speak for Euro bikes.