Engine detailing questions

[2manybikes]

One of my upcoming projects is cleaning and detailing the engine on my 79F. I've seen pics of some nice work on here, and quite a few different ways of doing it. I'm curious what the engines looked like when they were new. Heads painted or just cast? Side overs lightly polished and clear coated or not? I would be interested in hearing from anyone who has done this, as well as your methods. Thanks!

[TopCatGr58]

Hey there,

Here are mostly official Yamaha sales brochures of th e78E, 79SF, 80G, 80SG, 81SH, 81LH.

https://www.bikepics.com/pics/2007%5C07%5C07%5Cbikepics-955233-full.jpg

The bikes originally had clear coat on them, but aging usually caused them to corrode, fade, etc. Looks like in 81 Yamaha painted the JUGS black, along with the valve cover, that's how my 81SH came, and of course the MNS was totally blacked out.

Steve posted some tips about polishing tips and techniques. Most folks have learned that once the clear coat is worn off, some good polishing keeps them looking good and take very little effort to keep them that way. Others...JetMechMarty have discussed about some other treatments like clearcoat....YMMV.

T.C.

[2manybikes]

Detailing

Thanks for your reply. Some PO has sprayed something on it. Not sure what, but its not going to be fun to get off! Lacquer thinner will cut most anything, but not this stuff. Also tried mineral spirits. I'll just keep trying things till I find something that will get it off.

[MadHatter4119]

Try this...http://www.amazon.com/GAR343-KLEAN-S.../dp/B004Y1KX9E can find it in different size can...I didn't care for
the spray can kind...not as strong...Stuff should make easy work of it...

http://shop.advanceautoparts.com/p/prep-all-aircraft-paint-remover-ear322/10035245-P

[mack]

2 many

Depends on how well you want it to look. There is a factory preservative on the bare aluminum that needs to come off if you want it to shine. Some say aircraft stripper, I use paint stripper. They are all toxic to some degree. To do a really good job, the motor needs to come out and a partial teardown of most covers is required. Steve has a good thread on how to actually do the shining aspect.
If your looking to just clean it up, get the old bugs and road grim off the bike motor and other"once" shinny parts, I've found "goo gone" to be the best. It's easy to work with, less toxic and does a great job if you apply it with a softer sos pad.(they have different grits) Basically you should leave the factory preservative on the front of the motor which take a harder beating from rocks and bugs. The pipes hide most of that anyway.

[2manybikes]

Never thought of using paint remover. thanks for the links and reference to the post about polishing. I will take a look.

[jetmechmarty]

Do not use a steel wool on aluminum. Do not use a steel brush, or anything steel. Aluminum wool or brushes are OK. Brass is OK. Non metallic pads or brushes are fine. Steel wool or brushes can introduce galvanic corrosion.

[2manybikes]

Detailing

I have about talked myself into pulling the engine this winter, and doing it right. I had hoped to avoid that, but after looking at the rear of the engine, and all the places that would be difficult to reach, arghhh! Should I strip the whole thing before having it bead blasted? I will definitely replace the boots on the intake side of the carbs, as well as going through them. Everything else has been serviced, repaired, adjusted or replaced.

[zzay]

Do not use a steel wool on aluminum. Do not use a steel brush, or anything steel. Aluminum wool or brushes are OK. Brass is OK. Non metallic pads or brushes are fine. Steel wool or brushes can introduce galvanic corrosion.

does the same hold true for stainless steel brushes?

[mack]

zzay

Maybe sos pad was the wrong terminology. I mean the green pads you use in the kitchen. On a few hard to reach spots like between the fins and along the inside of the cyclinder sleeves, I use the soft black spiral brushes and small spiral brass brushes. They're good because you can bend them to suit the profile needed. It's a time consuming job to do it properly.

[mack]

zzay

This might be useful.

http://www.xs11.com/forum/showthread.php?t=27090&highlight=mechanics+stand

[jetmechmarty]

does the same hold true for stainless steel brushes?

Yes. Keep the steel off the aluminum. Have you ever removed a steel bolt from aluminum that has been in place for a long time? The bolt pops loose and comes out rust free and covered in white powder. The aluminum has turned to salts as the aluminum gives up electrons to the steel. That's galvanic corrosion. Without looking at the chart, I believe stainless is an even worse case. If you want shiny aluminum, keep the steel brushes/wool away from it. The green kitchen scrubbies are fine.

[Schming]

Never thought of using paint remover. thanks for the links and reference to the post about polishing. I will take a look.

To remove the original clear coat I've had great results with Permatex Gasket Remover in a spray can. If you can find it in a 12oz. spray can part #4MA that's the stuff

I removed all my covers, sprayed them, waited about ten minutes or until it bubbles up and rinse off with hot water before sanding and finally buffing to a mirror finish.

[MaximPhil]

And remember to put the tiny rubber spacers back between the fins.
Start with a can of degreaser (gunk) and rinse.
Phil

[motoman]

And remember to put the tiny rubber spacers back between the fins.
Start with a can of degreaser (gunk) and rinse.
Phil

Yeppers, +1. Reduces the harmonic vibrations of cooling fins and keeps them from getting internal fractures over time.