Engine Fasteners

[304065]

Does anyone have a 'fastener log?" For the engine or the car?

I'm working on a "fastener log" which lists:

Headmark
Diameter
Thread pitch
Length
Finish

for my engine. For example, looking at the workshop manuals (the definitive reference for concours) and the remaining finish of the fasteners on my 901/05 engine, it appears that all the small studs were black oxide passivated, and the other hardware finished in clear zinc. Over the years, this changed to cad or yellow zinc on the studs and nuts, as black oxide has relatively poor corrosion resistance (as I am discovering 41 years later)

I suspect that a similar log exists in the notebooks of the best restorers, but the labor involved probably makes it a highly guarded secret.

Here's one 356'er who posted some info:

http://www.brown-house.net/356project/hardware.html
__________________

[SP2]

Well, just for starters you will need 40 M6 x 1.0mm bolts and flat washers for the engine tin. Also M8 x 1.25mm nylock nuts. You will need a lot of them. I bought 100 for $7.50 from Tacoma Screw. I reused the M8 washers. (Valve cover gasket kits come with the fasteners though.)

Save all of your wavy washers, as I have found them hard to find.

A lot of the big bolts clean up real nice if you soak them overnight in carb cleaner. I got a gallon can, looks like a paint can, from the auto supply. Made by Berryman. Napa also sells a similar can, or you can even just buy a bottle of it and pour it into a new can. (But the Berryman can has a nice dipping tray with a handle.)

I also use a workbench disc grinder fitted with a wire brush wheel. Watch your hands, but this works great. Finishes it up shiny new, and you don't mess up the threads at all. BTW I also use antiseize when I reinstall them as a lube.

[304065]

James, thanks! Particularly for the tip about the wave washers.

I'm going to use a vibratory tumbler full of walnut shells or corn cob media to degrease and prep the stuff for replating with clear zinc. I don't want to be too aggressive because it might destroy the markings.

If one were to buy new M6 screws, these come with a headmark on them that says B-Y, even the ones from Stoddard. The originals, the ones the judges will notice, say "Kamax" or "Verbus" or the original manufacturers name. This is the kind of stuff that sets the restoration apart from the rebuild. Anal retentive? Moi?

[Grady Clay]

John,

Where plated, your original hardware was cad plated with no chromate conversion (that started in ’68). The change to zinc was in the mid-late ‘70s.

A couple of days ago Tom Scott (356 Manhattan winner) and I were looking over some hardware he has just had cad plated. Neither of us were happy with the finish. The prep didn’t get in the spaces in the lettering and at the root of the threads. It was also too shiny, a problem we think can be rectified by having them in some appropriate environment. We are considering pure oxygen and 100% RH at 150F. The goal is to have them appear 50-year old original as undisturbed they have a darker “fuzzy” patina.

For environmental reasons, non-original zinc is better.

“Anal retentive? Moi?”
Not at all.

Best,
Grady

[304065]

Some case hardware notes:

11 Case Through bolts, "Verbus." Black oxide passivated.
22 through-bolt washers, non-chamfered type. Finish a mix of natural steel and black oxide.

2 additional through bolt washers as above, these go on the permanent studs that hold the case together
13 acorn nuts. Some have yellow zinc, the rest are rusty.

19 M8x1.25 Hex Nuts for Case studs, 13mm ATF "V" for Verbus, 6G property-class. Bright steel finish, possibly cad.

19 wave washers, 17mm OD, 9mm ID, .5mm thick, black oxide

One M10x1.5, 15mm ATF hex nut, "V 6G" as above
One wave washer, 20mm OD, 16.6 ID, .8mm thick, black oxide

stay tuned

[euro911sc]

You guys are insane... hopefully I'll join you someday

Best regards,

Michael

[304065]

Well. . . a check of the parts book indicates there should be the following nuts. . .

900 084 004 02 hexagon nut M 8 quantity 21
900 157 002 02 hexagon nut M 10 quantity 2
900 076 010 02 hexagon nut M 6 quantity 17

This old parts book is amazing. . .

[euro911sc]

Please allow me to mend my statement...

304065: you are nuts!

-m

[304065]

Oh sure, make fun of me. But when you guys tear down an engine and put all the hardware in a big vat of degreaser and then try to put the engine back togther I GUARANTEE you will revisit this thread!

(not that I did that. . . . )

[911 tweaks]

304065- you the man!!!!!!! don't listen to those thinking you are wasting time.

This is a noble effort on your part for those whom want to do the rebuild COMPLETE and CORRECT.

Go get-em!!

Bob

[andrew15]

Get new wavey washers from our host for your rebuild. Pelican sells the correct thin wavey ones made by Wurth in bundles of 100 I think
AM

[KTL]

A great source for metric stuff is also Metric & Multistandard Component Corp.

www.metricmcc.com

[304065]

The mystery unravels a little bit. The original parts manual has cryptic notations like:

M 8 DIN 985-6S verz. SW13

Now, this happens to be a nut that holds the case together.

M 8 is easy enough, metric 8mm.

DIN is of course Deutsche Industrie Normen, and 985-6S is the particular specification called out.

The next part is harder. . but using the online German dictionary we see that "verz." is the abbreviation for "verzinkt" which means "zinc-plated."

And for the final piece of the mystery, SW 13. . . SW means "Schluesselweite" which means "width across flats" or in Maestro-speak, "ATF."

Now back to the specification. DIN 985-6 is a prevailing torque lock nut, FINE thread. . . with a nylon insert.

The trail ends there for now, rabbit just went down the hole. We know that there is NO nylon insert on the original nuts. . . perhaps an older DIN spec that was updated? I don't think even 985 is current, probably replaced by a new ISO standard. . .

[304065]

It gets weirder. One of the washers is listed as an 8,4 DIN 433 Al, Mg, Si F 32. What I took off the engine was a wave washer, 17mm outside, 9mm inside, steel, black oxide.

That means 8.4mm inside diameter, DIN 433 is a washer with a reduced outside diameter made out of steel. I don't understand what the Aluminum, Magnesium and Silicon are all about and F 32 escapes me.

[304065]

Duh. The manual I have was updated in 1969. Hence the nylock nuts, aluminum washers instead of steel wave washers, etc.

Unless I can source a parts manual WITHOUT the updates I'm going to have to pull measurements and specs off the original parts. No big deal, just more time.

[304065]

Some answers from the 356 crowd. . . the last 356 was a '65, so I'm going to check their manuals to see what they used. . . maybe it is right for a '66 before the updates for the mag case.

The work procedure for removing the starter motor or the engine will require removing one or both of the through bolts that secure each to the transmission housing. The assembly at each upper interface consists of a 10 mm diameter fastener, a wavy washer and a nut. Removal of either of these fasteners can be troublesome, especially the longer of the two, a M10 x 110 DIN 931 8g [now 8.8] that secures the starter motor. The DIN 931 specification indicates that this is a hexagonal head, partially threaded fastener with a standard [coarse] thread and the hexagonal is 17mm across the flats [ATF]. The wavy washer is a B10 DIN 137 where B means that it has a double curvature. The specified nut is a M10 DIN 934 6s, which is a hexagonal nut that is 17 mm ATF. Original finish was black oxide or the German equivalent for all elements of the assembly. What this means is that you will need tooling that is compatible with a 17mm "wrench size".

Credit: http://www.356registry.org/Tech/starter_removal_tiedemann.html

[304065]

I was wondering, "Did Roland ever write about this before he Flew West?" Turns out he did:

where to find nuts and bolts?

Hello

The Porsche order number: 900.074.037.02. says:
900 = regular normpart
999 = modified normpart ( Porsche only )

The .02 shows the revision or say the part is not the same like the 00 but a direkt replacment.

The descriptions is:
Hexagon bolt M8x35 DIN 931-8G Gal Zn9.

Now DIN stands for Deutsche Industrie Norm and was the german counterpart to SAE, BSP or BSA yet DIN isn´t direkt existing anymore as ISO took over. But DIN and ISO run parrallele as long still DIN parts are in existance.

M descripes Metric Standard Thread in form and tolerance M according to DIN 4579.

8 is the nominal Diameter
35 is the nominal lenght. On DIN 931 parts the length is without head.

DIN - 931 ( today ISO 4014 )stands for the Parts descrition. 931 is a hexagonal head bolt with partial threat on the shaft ( DIN 933 is same screw but threads up to the Head )
-8G is old for 8.8 witch gives the strenght from the bolt. ( In SAE you would have a pentagon or five star head ). This is descriped in DIN 20484.

Gal Zn9 is galvanic zinc coatet according to DIN 50960. The coating is minimal 0,009 mm on the worst spot ( corners & edges ).

The DIN 931 changed over the years. One example is that the spannersize went down from 15 mm to 14mm in 2WW and in mid 60´s to 13mm. Since 5 years the 12mmm head would be effective.

http://www.din.de/
DIN parts Searchengine :
http://www.boellhoff.de/D/aktuell/index.html
http://wueko.wuerth.com/
http://www.berner.de/www/html/home/home_index.html


Grüsse,
Roland

[jasam]

Wow this is a great advance for us the newbies of the porschephile movement!

Keep us posted John



P.S. pictures wouldn't hurt

[shbop]

John

Ae you set-up to do your own plating, or will you send it out?

[304065]

Jon,

I am afraid of the chemicals used in the plating process, so I will send everything out. Right now I am in the process of:

1) Identifying what SHOULD be on the engine. Basically, before anything gets sent out, I am preparing a list of every single part that goes in the engine. As you can imagine, it's a big task, but I don't want to start and then have to stop. Along with this goes the specifications of everything.

The trouble I am having is that my original factory parts manual was updated in November, 1967. This means that rather than specifing a standard hex nut, cad-plated, with a steel double wave washer with a black oxide coating, which is what is actually ON the engine, so I know it's original, the parts manual calls out a nylon lock nut and an aluminum washer, which was what was used on the Magnesium cases.

So I'm in the strange position of simultaneously looking for the original DIN spec, and not knowing what the original DIN spec is, because the DIN specs changed many, many times over a 30 year period, and in any event, are now ISO specifications, with DIN still running in parallel.

That's a long-winded way of saying that I'm going to have to look carefully at what I've got and backsolve into what it should be, forget the specifications. But the parts count will be helpful.

Then. . .

2) Clean, degrease and prep everything myself. One of the problems reported with doing old hardware is that the bulk preparation process doesn't handle details very well, e.g., the lettering isn't cleaned out, etc. I'm working on sourcing some extra hardware to account for wear and missing pieces, so once that's done, I'm going to soak everything in B-12, clean it with a nylon brush, throw it in my ultrasonic cleaner and then polish everything in a vibratory tumbler with walnut shell media BEFORE sending it out.

I'm going to shoot for the real deal cad plating, we'll see how much it costs. Probably going to have to use plain steel wave washers, and I'll have them done in black zinc, which looks like oxide, but is way more corrosion resistant.

The studs in the case are an interesting problem. If this were a Manhattan trophy engine I would remove them all (big job) and have everything black oxide coated. I don't want to fool around with removing all the studs, however, so I'm going to use some tool blackener to give the ends the correct finish. This should be good enough and offer some corrosion resistance without harming anything.

Speaking of the case, it's on the way back from Ollie's, it's been tumble-polished. I am seriously thinking of treating it with Zoop Seal to prevent oxidation, it's going to be that nice.

Ideally, the plater would be local, because I also have to have the door handles, window frames, window trim, mirror bracket, horn grills, headlight rings, rear window latches and rear bumperettes re-chromed. That is going to be mega bucks but I want it done RIGHT.

Another one of my long-winded answers. . .