Really great info here, thanks everyone, especially Grady. After the "incident" below, I cleaned up my 901 last night in prep for putting it all back together next week and will be ordering some Tectyl to coat it.

Question: The thin layer of factory body schutz is flaking off the bottom of the E with surface rust here and there, I was going to wirebrush grind the whole pan down to bare metal and coat with POR15. Maybe I read this all too fast, but should I instead coat with Tectyl? I'll probably just roller it on...POR15 or Tectyl.

Thoughts?

The carnage:
http://forums.pelicanparts.com/uploa...1148472591.jpg

Shaun,

No, Tectyl isn’t designed to be a primary coating on the chassis.

After you clean all the old undercoat, paint and rust off an area of the chassis, paint that has “primer” characteristics should go on. I am not a paint chemist but I think the critical features are to completely penetrate and seal the interface between the metal and primer. The other important feature for finish painting is to provide an excellent interface for the finish paint.

A primer is not intended to be a long term exterior finish.

I think POR has the first property and is very durable. I understand it is difficult to remove.

If your 911E is always a “work in progress” I would use heavy (multiple) coats of automotive primer for each section. It provides good short term protection and is easy to work and remove. You can extend its protection and longevity with an outer coating of Tectyl. This probably shouldn’t be considered as permanent protection.

Under the car good surface preparation, a good primer and then simple Plasticoat aerosol works great and is long lived. Semi-gloss black looks original. Gray lets you better see what you are doing (track car).


Tectyl is great for preserving aluminum parts and is necessary for magnesium parts. I use it during transmission assemble on the hardware (studs, nuts & washers) to prevent contact corrosion. After the transmission is completely assembled I use a paint brush to coat the exterior, usually multiple coats. The last operation is to make sure the important surfaces (axle flanges, starter mount, bell-housing interface) are free of Tectyl.

Tectyl is a wax not a paint. It is waterproof and provides good protection for surfaces both bare metal and painted. It is easily removed with solvent.


Randy, I suspect Porsche still uses the basic Tectyl product because it is so cost effective. Thanks to Wayne, Pelican Parts now stocks Tectyl 846.


This stuff is also suitable for protection of the exterior paint and trim for long-term storage. In the early ‘70s Porsche had a glut of new 911s in the port at Long Beach (LA). They were all sprayed with Tectyl. When they were finally sold to Dealers they were run through a “car wash” using contaminated jet fuel to clean off the Tectyl.

Best,
Grady

edit for my lame spellin

I bet you Tectyl would work great sprayed on the inside of door and other body panels to resist rust from the inside-out. I'm assuming that the drain holes are not plugged by the process.

Shaun,
I stripped the undercoating off of the pan of my car using a wire brush on a grinder, scrappers and MEK for clean it up (What a mess & a lot of work. I should have tried a heat gun, but didn't think of it at the time). After that I painted the surface with POR15. I wasn't interested in replacing the original terxture on the pan. I like the clean, painted metal surface look. Plus I really wanted the rust protection.

John,

Yes it does. I did this to my dad’s second Porsche – a ’67 912 Targa I built for him after his ’66 died of terminal rust in ’76. I had the car all apart and literally filled and drained all the double panels. It nicely wicks into the seams. It more than doubled the life of the car as it was a daily in Louisville, KY.

That was a NICE car – new soft window & top, 1750 cc, AFMSX 6:29, European heaters, Factory fresh air blower in gas heater well, “S” instruments (oil level inop), 6x15 Fuchs, early S brakes, sway bars & 19F-24.5R torsion, H1s with relays and the ’69 generator.

Irish green, black leather, black/green/white hounds tooth, ‘67S carpets.

The car was practically new (12K miles) and had been lightly hit in the passenger door and latch post. It had been stored inside for the past 8+ years.

Sorry for the digression but as nice as the car was it was clear the inner panels and seams needed protection as they were absolutely bare metal. I drilled holes to fit little Porsche plastic plugs in places only accessible while the car was apart. You can’t find or see them when it is assembled. Where there weren’t drain slots I made them. I plugged the drains with putty and sprayed and semi-filled the double panels. I then pulled the putty plugs and let the Tectyl drain out. It quit dripping after a few days. After a month or so all of the solvent had evaporated.

Pelican joefranz is working on his ’73. Last fall he found a piece of insulation/sound deadening in the cavity just below the rear window (coupe). That stuff was still wet and the car hadn’t seen a drop of water since it came out of the body shop five years ago. Fortunately our low O2 prevented any damage but at sea level that would have rusted from the inside. Some Tectyl will make that 911 last forever.

I suspect you can coat every cavity surface and not retain much more than a pint of product.

I always wondered why early Porsches were so prone to rusting. The joke was the Factory primed them to rust. In fact it was a post here about a year ago that finally showed me the cause. There is a video of the 356B production – about ’60-’61 as I recall. After the body is completely manufactured and semi-assembled fitting the panels, it is run through a furnace (600F+) to burn off all the preservative and lubricating oils on the panels –inside and outside. These oils were preservatives from the sheet steel manufacturer and lubricants in the forming process. Had Porsche simply cleaned the exterior, these would have helped prevent inside rust. As it was, the interior (unpainted) panels were preped to rust.

This is a really good application for Tectyl.

Best,
Grady

edit for my stupid typos.

Thanks Marv, if it's half as much fun as this project was below, I simply can't wait to dig in, especially lying underneath it all! ;) My undercoating is very thin and flaking off, I'm hoping a serious scraper will provide the best results, then the cup wire wheel on the grinder. On the metal prep side, do you have any tips for spraying up onto a "ceiling" of the underside of the floor?

BTW, I've found POR15 to be a better product than Wurth Rust Guard.

http://forums.pelicanparts.com/porsche-911-technical-forum/152355-project-73-911-r-rs-week-3-a.html

Shaun,
I didn't spray metal prep up onto the pan. I cleaned it as well as I could with long gloves & acetone on a rag. Then I did the same with the metal prep & wiped it down with water on a rag afterwards, dried it & painted it. The chemicals were pretty stinky & I was happy I had plenty of ventilation.

Cost Effective? The Tectyl is priced at $65/gallon -- could that be a typo??

Randy,

I’m sure Porsche AG buys it in RR tank-car lots from the Daudert Chemical plant in the Netherlands.

It took some effort (better part of a year off and on) to find the company who was repackaging this in double sealed 1-gal containers, in a sealed plastic bag and then in a “legal to ship UPS ground” HD cardboard container. Wayne’s biggest hurdle was having the certification to allow UPS ground shipping. Still, he only can ship that in continental US. Our neighbors to the North have to find a Canadian supplier.


Fifty years ago you probably could go to your local Valvoline wholesaler and they would drain some into your open 5-gal bucket for $2 and leave the faucet dripping on the ground. No OSHA Materials Safety Data Sheet required. We all know where the $65 goes – it leads all the way back to the well-head and the requirements to drill in the first place. Yes, it is expensive. No, I wouldn’t have it any other way.

That gallon will probably last you (and an occasional friend) your lifetime.

Best,
Grady

Thx - my point is not whether the price is fair (re markup, hassle, etc. -- and thank you Wayne for going thru this to get it), it's just the cost. Maybe I can find a few folks around here to split a gallon.

Do you really think a pint would be plenty? How much do you think it would take to do a transmission?

Any one in the Vancouver, BC area want to share a gallon?

Randy,

If you don’t spill it all over the place, a double coat on the trans might take less than ½ pint. A gallon will coat a LOT of transmissions.

Best,
Grady

Thx - maybe we should have it drop shipped to the Parade in PDX -- we can ladle it out in beer steins.

Hey guys, i've been following this thread and was very interested in the Tectyl until I found a CRC product in spray can for about $11. It's almost identical to the product Grady found. If you don't like the $65 cost, try this. Look for it at any Marine / boat store.


CRC Heavy Duty Corrosion Inhibitor, once applied, forms a corrosion-proof film that remains flexible, won't crack, seals out corrosive salt air and moisture. A coating of corrosion inhibitor provides long term protection even in challenging marine weather, and can be removed with most petroleum based solvents or with CRC's own degreaser.

Bob,

I suspect the CRC stuff may even be repackaged Tectyl 846 somewhere up-stream. The Tectyl 846 is similarly packaged and priced. Yes it is convenient and I think Wayne considered it. The difference is it costs $128.00 per gallon packaged that way (a little less than a dozen cans).

I like the idea of splitting a gallon among several local Pelicans. You get the best of both worlds.

Best,
Grady

Other products that have been discussed in previous threads are:
1. a Starrett product in a spray can
2. Corrosion Block, also in a spray can

Here is something of interest, apparently done by a MIT student:
http://web.mit.edu/charvak/www/Science/Corrosion/corrosion.html

Why doesn't one use POR15 in grey or black to cover the case once cleaned and it should last quite long.

tshih - personnally, because I think that would be uugly....... :)

you could also spray the POR15 with silver color paint once treated to look good but the topic is preservation not esthethics.

Everyone on this thread needs to go read this one: http://forums.pelicanparts.com/porsche-911-technical-forum/297495-gibbs-metal-treatment-anybody.html