25 hp engine case coating

[Splitdog]

Careful! Never trust a fart. Those seals are old and cracked.
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CH³NO²

Z = z² + C

Der Blitzkrieg Kafers

#notacallooker

[r39o]

[52HoffmanSplit]

Dow..? I dont need no steeeenking Dow.

Wonder if I can get it Dyed Green for St Patricks Day?
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DB

9/1950 Hoffman Standard
11/1966 Porsche 912
10/1966 Porsche 912
7/1968 Type 265 Double Cab
10/1958 Type 117

[Splitdog]

Erin, go braless!
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CH³NO²

Z = z² + C

Der Blitzkrieg Kafers

#notacallooker

[VWwerks]

I have had some luck with this. I took a sledge hammer to an old case so I had a lot of small chunks to practice on and only ruined 1 case that was shot anyway. I could also make a smaller batch of the solution. I just did some test pieces but gave up on it a couple years ago due to lack of time.

First immerse case in the HF acid solution for 5 minutes, then rinse throughly.

Then immerse in the dichromate solution for 20-30 minutes. Rinse throughly in cold water, then hot water, then dry.

hydrofluoric acid solution
Makeup - hydrofluoric acid 1 part
Water - 4 parts
Temperature 70-90F

Dichromate solution

sodium dichromate 20 oz/gal

calcium or magnesium fluoride 1/3 opg

Temperature: boiling

pH 4.1 - 5.6
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www.VWwerks.com

[ZwitterND]

Dang Jim I can't near say dem der words let alone knows where to find 'em! You recon it's something I can do in the tub? j/k

Seriously, thanks for sharing !
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Bill

[johnshenry]

When you have a half dozen or so ovals laying around like Jim, you can afford to 'speriment like that Bill ...........
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John Henry

'57 Deluxe
'56 Single Cab

[VWwerks]

The problem with this is the chemicals are so expensive you're better off sending it to Joe unless you have many cases you want to do.
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www.VWwerks.com

[banana split]

What kind of prices are Eric and Joe charging for this service?
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My Beetles :
1951 Crotch Cooler 11G Split Ragtop
1953 Zwitter
1964 Chop Top

[Splitdog]

"I'll paint any engine case, $29.95!"

This will look way better than any fancy schmancy process. Especially if applied with a large brush.
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CH³NO²

Z = z² + C

Der Blitzkrieg Kafers

#notacallooker

[johnshenry]

[HerrrKafer]

[sweden]

Have any tried this?

Chemical Name: Dow 7 Magnesium Treatment Compound
Synonyms: Dow 7

Product Description:
The Dow 7 magnesium treatment compound is provided as a pre-
mixed powder that is dissolved at time of use in 4 gallons of water.
This will produce enough solution for a 4-gallon immersion bath.

The complete process will require the initial activator solution which
is available as either Type I or Type II. Scroll down to the “Related
Products” section below to see the activators and description for their
proper selection which is alloy dependent.

Introduction:
Magnesium and its alloys are more galvanically active than even zinc
on the galvanic series. Magnesium will form a strong galvanic cell with
every other metal it comes into contact with and is always sacrificial.
When magnesium corrosion is detected, it requires immediate attention
or the corrosion will spread throughout the entire structure. Therefore,
these alloys must be properly protected from corrosion damage.

Background:
Dow 7 is a good choice for both new and overhauled parts that have
dissimilar materials such as inserts, or where conditions will tolerate a
less robust and less costly alternative to Dow 17 anodizing. It makes
an excellent paint base and provides the best corrosion protection of
the available chemical coatings for magnesium.

Dow 7 is a chemical conversion coating which results in no appreciable
dimensional change to the component. The surface of components coated
with Dow 7 is changed to a brassy or dark brown finish depending on the
alloy. Note that this coating film is dielectric (non-conductive).

Process Description:
The complete process requires two steps. The first step is an activator
immersion which is done at ambient temperature in the range between
70ºF and 90ºF. This is followed by a distilled water rinse.

The second step will require a stainless steel vessel that will allow
the heating of the Dow 7 solution to boiling point (200ºF). Immersion
time for the parts is about 30 minutes, also followed by a water
rinse before allowing to hang dry for 24 hours.

Specification & Certifications:
The coating produced by proper application of the contents of this solution
conforms to SAE AMS-M-3171, Type III (formerly MIL-M-3171, Type III),
sometimes referred to as “Dow 7”.

Exceptions:
Not for use on the following magnesium alloys: EK30A, EK41A, HM31A,
HM21A, HK31A, La141A and M1A. Due to their chemistry, no coatings
form on these particular alloys.

Application Notes:
Castings containing bearings, studs, and inserts of brass, bronze, steel and
cadmium-plated steel may be treated using this process. Note that aluminum
inserts will be rapidly attacked by the Hydrofluoric acid present in the Type II
activator.

Use alkaline cleaners containing less than 2% caustic for ZK60A, ZK60B and
some Magnesium Lithium alloys, as dimensional losses due to etching may occur.

Limitations:
Extended exposure of the developed coating to elevated operating temperatures
in excess of 150ºF will dehydrate the coating resulting in reduced corrosion
protection.

Packaging/Size:
Powdered chemical compound comes packed in 1-gallon can to be dissolved
in 4-gallons of water.

http://www.chemical-supermarket.com/Dow-7-Magnesium-Treatment-Compound-p652.html
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Me and my sons cars Typ1 -49 -50 -51 -52 -52 -53 -53 -54 -55 -55 -56 -56 -57 -58 cab -64 cab
T3 TriStar airride with Audi 1,8T engine and Porsche 996 gearbox.

[stefi.g]

as Mika wrote I do same way on my cases...

[cory464]

kinda funny, 70 years ago folks were trying to keep cases from corroding and could care less what they looked like, but now everyone cares what they look like and don't even drive them.

[Mr. Okrasa]

These are mine.....

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See my Instagram: https://www.instagram.com/okrasa/

1959 VW Karmann Ghia Coupe / Bamboo-Green / Denzel 1300cc / OG. owner, paint

Denzel engine running. See this link: https://youtu.be/DgUlsQDTXTE

VW www.Okrasa.com
356 www.PreA356.com

[splitjunkie]

Personally I think anyone trying to do this at home should have their head examined. These are some serious chemicals and even if you don't injure yourself or your family in the process, what are you going to do with the leftover chemicals?
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Chris

You know, a lot of these scratches will buff right out... Jerry Seinfeld

[Mr. Okrasa]

[Mr. Okrasa]

Just got these 36hp VW blocks back from a fresh coat of chem. treatment to start the New Year off with some trick engine builds ; - )

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See my Instagram: https://www.instagram.com/okrasa/

1959 VW Karmann Ghia Coupe / Bamboo-Green / Denzel 1300cc / OG. owner, paint

Denzel engine running. See this link: https://youtu.be/DgUlsQDTXTE

VW www.Okrasa.com
356 www.PreA356.com

[Jorge R]

I can now offer this service for 25 HP and 30 HP engine case coating in Portugal - Europe.