I don't even want to think about cosmoline..... I had a hard enough time cleaning that crap off my SKS when I first got it. And there are still places that I can see it..... Was this used on these cars?

 

That is a subtle leak alright.

 

abso$*#&inglutely agree with that!!

I've even got it on the inside of the wheel well liners which are plastic (well sort of tissue paper actually) ... WTF was Fritz thinking when he sprayed it there and lots of other similarly ridiculous locations.

I find wetting it with degreaser, and leaving it wet for a while, and then scrubbing the crap out of it eventually gets it off. Some thick layers I've just had to scrape off after softening.

 

Yes - Crawled under the 95 GTS at the Porsche museum; here's some cosmoline in all its glory...

 

I'm not looking forward to cleaning that all off my car..... =(

When I cleaned my SKS I just used some gas and rags..... Could this same method be used on my 928? I wouldn't use the gas on plastic parts but what about everything else? Gas seems to dissolve it very easily....

 

Gas, odorless mineral spirits, simple green, kerosene, brake cleaner, histoclear, citrus oil, brown royal- any and all of these will work on cosmoline, but there are nooks and crannies on the underside where the crap is 2-3 mm deep, and the only way it's coming off is combinations of heat, solvent, and scrubbing. I have (more or less) de-cosmolined three cars now, and although you'd be more than the normal 928-owner-level-of-insane to do it just for cleaning, the best way is to put the car up on stands and disassemble. Everything. For the third car I ended up taking the suspension to Greg's shop and running the suspension pieces through his parts washer, which only softens the cosmoline, then it had to be scrubbed in the other 20 gallon parts washer with brass and/or nylon bristle brushes. I did my GT lying on my back, spent far more time than with disassembled pieces and didn't end up with as complete a job.

 

Uh, try to ignore the severely undertreated OCD sufferers here (Rob - where are your pills?) and just wipe off the areas that concern you and see what reappears later. Oh, OK, some simple green and a brush will help loosen it.

 

In our quest to be able to post pictures of squeaky-clean undercarriages, we might forget what the cosmoline was put on there for. In all but the most gentle climates and driving conditions, it protects the coated parts from abrasion and corrosion. Rob's picture of 90S4's undercarriage doesn't include the note that the whole undercarriage was disassembled. All those aluminum suspension bits were carefully cleaned, soda or walnut blasted, then sprayed with clear before they could start oxidizing again to grey. The tub was resprayed white, including all the sound deadening/protective finish areas. All the hardware was removed and replated. The owner is with a restoration company and has easier access to these services than most of us. Bottom line is that spending a day or three with cleaners and a scrub brush won't get you to that condition, and without the preservation steps it won't stay pretty for very long. Cosmoline is one of the preservation steps that the factory used.

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Some of the posts include tips to use petro solvents of various flavors. I know that there are more than a few folks who believe that spray brake cleaner is the best thing since natural mother's milk right from the source. Truth is that exposure to that stuff (not referring to the natural mother's milk here...) is known to cause brain damage, plus kidney and liver problems. It is fat soluble obviously, so it travels freely into the skin and through the bloodstream. Inhaling the vapors adds another path to get into the blood. Gasoline, Diesel fuel, kerosene, acetone, lacquer thinner, MEK, toluene, SSS, pretty much any petro solvent will have the same dangers to some extent. So choose your weapons carefully, wear protective gear including serious gloves and a vapor respirator, with serious ventilation. Virtually all of these solvents are flammable, and some are explosive in the right concentrations. So you don't want to have a nice heavy layer of explosive fumes making it's way over to the water heater pilot lamp in the garage. Work outside, away from the house, with a charged water hose and a fire extinguisher handy.

 

I understand the purpose of the cosmoline as an abrasion and corrosion preventative ... but I have to still scratch my head at the seemingly random application in many areas. In some areas on my GTS it seems like they employed the village idiot to put it on, in locations where there couldn't possibly be any corrosion or abrasion of the parts it's been applied to.

Edit: On areas where cosmoline has been applied hit and miss on both my cars, I don't see a corresponding hit and miss pattern of corrosion or abrasion once it's been removed, which must bring into question whether it in fact has any significant benefit.

 

I think the cosmoline on my dry-weather- and smooth-roads-only car is there as an indicator that something has been worked on. So I remove it from the serviced parts and surrounding areas. It's akin to 'destroying evidence' I guess.