When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
I've had the fan housing for my '98 C4S vapour blasted along with a bunch of other engine and HVAC components. They have all come up lovely and shiny as new, so I would like to keep them that way if possible without them turning in to a corroded mess.
I've coated the alloy air tube, air diverters, a/c compressor and a/c pedestal, with ACF-50. Not sure if you have that in the US? Its a corrosion inhibitor for metals as used on planes and now more commonly motorcycles to prevent corrosion of alloy parts. This should keep them fresh for some time to come and I can apply more to the visible parts once on the car if required. When it comes to the fan housing however I am not so sure on the route to take. I want it to be factory finish or as close to and it currently looks great freshly vapour blasted. I'm just concerned that the coating of ACF may not be enough longer term, as getting to the part to maintain it will be hard once back on the car.
I understand the part is a magnesium alloy (don't know if anyone can confirm?) and with that painting can be difficult as the mag can gas and push the paint off. Also this isn't the factory finish.
Does anyone know if any coating was used by Porsche from new? Or if you have any advice on how best to tackle the refinishing of this part to keep it looking fresh please do share.
The black chromate was supposedly treated with Tectyl (a corrosion preventative made by Valvoline) at the factory. I'm reading that was the process for quite some time and there are some friends that restore the early cars that have dealt with this too. Tectyl seems to be difficult to source in the U.S. now. I'm finding out via some sources that using another "oils" produces good results. The PO of my car, who does lots of restoration projects for himself, likes to use Gibbs Penetrating Oil on such magnesium parts. I had read about people using it on old "hot rods" on the mag wheels to give the nice dark gray patina.
Interestingly, this black chromated magnesium part is a bit of Porsche history.
I used the Gibbs Oil on my fan housing and it's doing well. I did not have it media blasted beforehand though....
So do we think the current silver finish I have here post Vapour Blasting is as per new but at the factory they applied a corosion inhibiting oil that turns the part that distinctive grey?
So perhaps ACF-50 will be fine, or I need to find some of this Tectyl and DIY to get it to factory appearance and durability.
So perhaps ACF-50 will be fine, or I need to find some of this Tectyl and DIY to get it to factory appearance and durability.
Tectyl (i don't think I have ever seen on a 964/993 fan...) needs to be reapplied every 12 months (per Porsche) and ACF-50 has a 24 month lifespan. You need something more permanent over the bare vapour blasted metal.
Is the factory finish bright silver like my blasted part, or are they chromate coated then something over the top of that from factory? I understand from online reading that black chromate isn’t a corrosion inhibitor in its own right and usually just forms the base prep coat.
On my 964 we vapor blasted and then PVD coated the fan and housing.
On my 89 carrera we vapor blasted and just clear-coated them to keep the natural look.
I'm not exactly sure what exact paint they used, but it's held up fine since the year I had it done. You can see the results below. When we blasted the metal this is what it looked like, and we just cleared it in.
Stunning Porsche 356A Super GT Speedster Auction Fails to Meet Reserve
Slideshow: One of the rarest Porsche 356 Speedsters ever built has resurfaced, offering a glimpse into a little-known chapter of the model's competition history.
Theon Goes Full Carbon Fiber With Stunning New Build
Slideshow: Built around a carbon-bodied 964 and a naturally aspirated 4.0-liter flat-six, this bespoke commission highlights how far the restomod formula has evolved.
Tuner Is Converting Porsche 911s Into Shooting Brakes
Slideshow: A Polish Porsche specialist is moving ahead with one of the most unusual 911 conversions in recent memory: a shooting brake version of the 991-generation sports car.
This Coachbuilt Creation Is A Modern Take on the Legendary Porsche 917
Slideshow: A Porsche Carrera GT has been transformed into a one-off coachbuilt machine that blends analog supercar engineering with styling inspired by the legendary 917 race cars.
Is This Convertible Cayenne A Steal, Or A Returnless Investment?
Slideshow: A heavily modified Porsche Cayenne convertible with faux wood trim and a long list of flaws recently sold at auction for surprisingly little money.
Fan Housing Refinishing
