65C Garage Find, front floor replacement

[Jbrooks]

Well Folks, the 912 Interior is finished so Its back to real cars. A few months back a local guy found a Slate Gray/ red 65C in a friends new wife's garage. Her dad had the car for 15 years started a restoration,got it to 90%. He fell ill and pushed it in the corner of the garage south of SFO, put the loose bits in boxes and threw a cover over it.



15 years later he daughter inherits the house, contents and car still sits in the corner. She marries a friend last summer, he wants it out to make room for his Miata, and Cliff Buys the car sight unseen.

I looked at the car after he brought it to the island. Its a Jewell. Straight, dry, complete,it took me 45 minutes to verify it had been painted. I had one small drip inside the reflector hole inside the rear fender. It sat undisturbed so long there were little dust dots, from between the weave in the cotton cover. Absolutely an amazing find.






Three months later it drives. Did the normal stuff, rebuilt the brakes, flushed the fuel system. Marvel oil in the cylinders. Plugs and points looked new electrically every thing was good. Compression was 125psi after a couple weeks of oil soak, and hand turns. Fired up after 30 seconds, blew the carbon and rust out of the mufflers, but no leaks or strange noises. Good idle, but a little brown smoke on accelerating.

Took out the leather seats and sent them it for an oiling and cleaning. while the seats were out we sat on a spare tire to bleed the brakes. Mistake NO#1. After 20 minutes of bleeding found a large dusty dirty spot on the floor on the drivers side. Rust from the under side floor. Found a couple cracks in the center where the front of the tire pressed against the floor sound deadening. Peeled up the original horse hair tar paper and crap, the floor is paper thin. The floor "Tap Tested Fine" but it had rusted under the undercoating inside was OK outside had a layer of rust under the Shutz.

They are not all that bad but since Al Zim has new ones, the Saga begins.

[Jbrooks]

Floor came in, looks good. Drove the car down to Bob Brooks for the hot work


Up on the rack for better inspection



Inside drivers floor, not all that bad. Only thin under the drivers feet, pedal area good, aft of the doubler still original and bright under the sound deadening


Passanger side is still intact, bright under the tarpaper. Debating if to do the front half complete or just the drivers half



Thanks for looking

[Don C]

My $.02...just do the drivers side.
Lets see what the pros say.

[bbspdstr]

Damn, I thought Mr. Brooks is a pro......so I'm gonna say what he already knows.

Here's what I think, not 'know'; (1) if I had it to do over again, I would have cut out and replaced the same quarter of the floor in the C-2 I'm finishing now, but stupid amounts of time went into straightening damage and bad prior 'repair', not rust, and it was to be able to say honestly..."The whole underside is ORIGINAL." That rust doesn't allow that honesty unless it's wire-brushed, coated every which way from Tuesday with POR-15 and a stop sign is riveted on the inside, under the mats...like 'back in the day.'

(2) I have NEVER said..."damn, I didn't need to cut that piece all the way to over yonder, it's better than I thought." It's always worse than it looks.

(3) good 356, so do it at least 'half' right and use the whole front half you'll need to buy. Before pressings or 356s had enough value to buy a Factory part, under the tutelage of Jack Heron, I made each section over a block of steel and joined like quilting, just fixing what was bad AT THAT TIME. That was then, this is now and the parts are cheap compared to labor, but I'd do a very detailed search of the whole floor, based on the iceberg theory of what's seen at first.

But that's an opinion...and thankfully, "it's not my job."

It will be good to see what others think.

Best of luck and kind regards,
-Bruce

[Jbrooks]

Bruce

I am not a pro, just old. I bought the front half of the floor from Al. I plan to wire brush the underside today and tomorrow, if that's good I may splice in part of the drivers side. Its good forward of the toe board, and about 4-5 inches around the perimeter, seat mounts etc. Looks like I have good bones to tie into.

Their only cracks from the tire. No flakes or exfoliation scales just rust dust. The photo has some of the padding chunks, but if you look close, its just cracks. I am in a quandary, I want to keep it as original as possible, but stop the rust. I am thinking about Formic acid and the POR before the Wurth Schutz on the entire underside when we are done.

The damage is not all that bad. It just flexed from the weight concentrations. If it were my car, I would treat it and Put "All Metal Filler" over the cracked area re undercoat and keep driving it.

[Jbrooks]

Floors were not too bad. Drivers cracked and the passengers was thin forward of the toe board. So off to work we go. Pushed up the floor and the cracks filled but not weldable, .15-.25mm remaining. Cut out both side so they will match.

Remnants


So now Fred Filntstone can race it


Have 25-30mm solid edge all the way around. Seat mounts were still solid and not rusted so we left them in place. Good edges all the way around for the new patches. Good evenings work, Bob has measured it all and now to cut the fillers.


Looks like most of the damage was trapped water under the sound deadening or between the under coat and floor pan.
Thanks for looking.

[Phil Planck]

John
Glad to see that almost all of the front floor pan was removed. Before reading Bruce's comments, I was of the opinion to replace the whole front pan. Not sure about leaving seat mounts in, as they can be fairly easily removed and reused on the new pan with possibly a "safer" solution in case of an accident. But the current way should keep seat slides working without a lot of fuss to get that setup correctly. That slate gray was the original color of Foam Car. Have not seen one in person yet that I liked, but this one looks pretty nice in the pics.

Phil

[Jack Staggs]

Their only cracks from the tire. No flakes or exfoliation scales just rust dust. The photo has some of the padding chunks, but if you look close, its just cracks.

I've read this probably 20 times, and for the life of me, I can not figure out what you are talking about. How did a tire cause the cracks?

[Jbrooks]

Jack

The interior and seats were pulled for cleaning. While doing the brakes and hoses we put the spare tire in the drivers side and sat on it to reach the pedals. Over a couple hours of squirming around on the tire, it flexed the floor. The wheel was on the cross brace, tire sidewall on the center of the floor. It was foil thin where it cracked, less than 1/4 of a mm. The original sound deadening was still in, we did not notice any flex until there was a 2'x2' black and rust pile of dust under the drivers side on the floor.

The original inspection and tap test, spring loaded center punch test were fine. Floor seemed solid and original. Turns out in a couple places 3/4 of the original thickness was powder.

But all so good the floor will be in tomorrow, then formic acid rust conversion, prime, paint, undercoat.

[Jbrooks]

Phil

I thought about the seat mounts, I believe this will be as strong as original.

I have a slate gray roadster, it's a great color, other than it"s hard to match now. I have tried Glasuirt, by RAL number, never quite right. Finally got a formula from the Glasuirt Rep.

I did get one close, by sending the original formula to a paint company in Miami. It was very close, but when I looked at the can tag NO 3cc of Green! Spray out was very close, but not correct.

When I called and complained after the third try, the owner said his "formulation / mixer guy" SEZ there is NEVER any green in gray. Then I Said " I sent you a formula, follow it. ". Yes the next quart was good.

[JTR70]

WOW John, aren't you the great 356 friend to have around. Anyone willing to tackle floor or partial floor pan replacement lying flat on their back with the car only inches off their chest is true buddy in my book. Its shaping up to be a nice repair! Thanks for sharing your progress.
Justin

[Jbrooks]

Took yesterday off to do a couple sets of carburators. I love building Solex's Today fit the patch panels. Did the final filing and fit.



Panels were a little different than original floor but not enough to make a difference.




Welder up tonight, a little hammer work around the seat pads but so far so good.
Thanks for watching

[Jack Staggs]

Jb et al... Rot of the floors, limited to the area in front of the driver seat and rear of the pedals, in otherwise dry non-sunroof coupes seems to be a West Coast phenom. I've seen quite a few, and repaired several in just the same fashion as you. In fact, I have one in my stable with the requisit old school metal realtor "for sale" sign standing in for probably 20 years now. Anyone care to venture a guess as to why? BTW, T6 fuel tanks suffer a similar fate, but for different reasons.

[Phil Planck]

Anyone care to venture a guess as to why? BTW, T6 fuel tanks suffer a similar fate, but for different reasons

Lack of cup holders and acid from Starbuck coffee or some other west coast brew?

Ethanol?

[bbspdstr]

The floor rust I have seen forever is inconsistent. I have seen one side rusty front to back and the other side of the tunnel just fine. I figured that the rusty side was down on a sideways sloped parking spot or next to a damp wall in a garage.

The driver's front floor is easier to understand. Various climates have at least SOME rain and/or snow and that comes in on shoes or boots. That side also has the most chance of a window left down when it rains.

That area has the most flex, too. Pedals and seats always make SOME motion effect while driving and overlapped seams and sandwiched sound-deadeners (which dry out and shrink) on bare unibody sheet metal add to the fact that the bare metal when built into a body was not coated with anything more than an enamel primer over what could be seen, not inside or between vulnerable areas.

"Rust never sleeps."

Add to that the absolute that Porsche DID NOT want or expect these cars around past about 1976 for the last of the 356s or 1983 for the last of the first 900-series. We are voiding the dictates that the Porsche accountants gave to the engineers....but we are also re-creating 'hack proof' automobiles....a new threat with recent or current vehicles that are computerized and connected to the net!

Oh, my additional theory on why Speedster doors have been the last to rust is due to them having no windows and an overhanging upper edge... even if rain can get in straight down (top up OR down)

Can I get an "A-men" for points and carbs, manual windows and transmissions?!

Gas tanks, T-6 in particular, are subjected to the evaporation of the gas as it vents and the ambient air, always having SOME moisture, condensing and making tiny amounts of H2O settle and build in the lowest part of the tank, the gas outlet area. Additional rust develops in adjacent areas if the parking is not level. Yes, ethanol (gasoline with alcohol) plays a part in woes but not much in the rusting aspect.

The earlier tanks were made from a tinned steel (I understand commonly used in Germany for roofing) that unless damaged, was almost a lifetime containment solution. Still, once that coating is broken, corrosion spreads and tanks are ruined. Again, NO parts or systems were designed to last forever...and here we are, attempting to preserve these cars to be around long after anyone cares.