How would you clean an aluminum crankcase?

This is for a brass car. The case is throughly oil soaked. I'd like to get it as close to antispetically clean as possible before the engine goes back together. I am presuming there must be some chemical method. This is basically the same problem as cleaning a cast aluminum oil pan... 100 years of sludge permeating the metal.

And... I apologize because I just did a search and found I'd asked this question a year ago. I still haven't found a good solution though. I looked into soda blasting but it simply isn't available anywhere nearby. Ideally, I'd like to use something chemical, even if it has to sit for weeks. There is no hurry... I liked Richard's (in Bolivia) idea of just soaking it in degreaser and detergent. I'm wondering what might be the best to use. Money is a problem because I don't think I can swing a 55 gal drum of carb cleaner.

I would do just as you said. Start with cleaning it with a solvent such as Varsol to knock off the worst of the gunk and then finish it using a liquid dish washing soap. I assume that the metal does not have a clear coat on it? Ferous parts would need to be oiled.

Another option would be to take it to an automatic transmission shop. They have industrial dishwasher contraptions they put the cases in to clean them out.

Cheers, Steve

Electrolysis works well for cleaning old rusty iron engines, what would it do for aluminum? Might be worth trying on some scrap Chev 350 pistons or the like. If it works, and does not attack the aluminum go for it.

All you need is a big, non metallic container of water, and a handful of washing soda. Then connect to a battery charger.

The electrolysis cleaning method only works on ferris material and really only for rust removal. It will loosen paint and such in most cases, but grease, oil and simular materials will not clean well as they block the electric current which is required for the electrolysis to happen.

I have used oven cleaner, the aluminium will be as clean as the day it was made.

I like the idea of some not-too-strong cleaner, like Pinesol or a citrus-based product, directly applied or diluted somewhat with very hot water. Use a scrub brush with nylon or other non-metal bristles. Don't use a stainless steel scrub brush because that can also cause stains. Wear elbow-length heavy rubber gloves and safety glasses to keep the stuff off your skin and out of your eyes. Strong detergents and grease removers like Purple Power or even Simple Green may eat into the aluminum or leave it stained. While oven cleaners and other things with sodium hydroxide may take off the carbon, then will rapidly etch the aluminum. There are also industrial cleaners like ZEP-a-lume (truck/trailer wash) will clean and brighten aluminum, but be sure to follow the directions and dilute it a lot because it has hydrofluoric acid in it - very dangerous to skin and eyes! A cast part is never going to clean up like a part stamped from sheet or machined from billet. The big dishwasher at the transmission shop, as Stevemo suggests above, sounds like the right thing, and you don't get exposed to hazardous chemicals. As a final step, you can use some Brillo or SOS pads with their built-in soap to polish it up.

I should have thought any decent boatyard in Rhode Island could link you up to a soda blasting company, if you need to go that way.

BathTub full of simple Green

The only soda blasting place I could find is in Newport and specializes in fiberglass boats... with $200 minimum charge for what they admit might be 15 minutes work. Also, I'm leery of any abrasive on a crankcase because I can't be certain I will get it out of all the (admittedly few) oil passages. These were plugged on the ends after drilling and it isn't worth the effort to try to unplug them. I feel the same way about caustic solutions. I remember years ago a story circulating about the guy who left a an aluminum crankcase in the hot tank over the weekend... and came back to a half melted blob only identifiable by the pile of threaded inserts. Its critical to me that I be able to paint the inside of the crankcase... actually, some discoloration would not be a major problem as the outside will also be painted with aluminum paint as was the custom at the time.

At the moment I'm thinking of a plastic barrel full of water using a product recommended by one of my antique machine friends... its basically washing soda with a few additives and maybe some non-foaming dishwasher detergent. The idea is to heat the barrel with a drum heater and agitate the water with a submersible pump... and maybe leave the part in for a few weeks. I haven't done this yet... this is just exploratory so far but I'll have to do something soon because I do not like working on dirty parts and I've some serious machining to do in the next 3 weeks. After everything is done it will get the cleaning treatment again.

Does anyone know if TSP reacts with aluminum? The box says it will darken it but are there any other effects?

Thanks for the ideas!

The problem with early brass car aluminum is one of being porous. The oil soaks into the pockets in the castings, and no amount of surface cleaning will remove all oil. Talk to anyone who's tried to weld an old crankcase, with heat the oil just keeps on seeping out of the casting.

The used to be a method called "vacuum degreasing" that would suck all the oil out of an aluminum casting, but the methodology seems to have been lost.

Some machine shops have baths that can clean aluminum, but one has to be careful and understand what they're doing, and how it may affect the aluminum.

If you can get it clean, then coat the inside with Gasoila, and usually the outside of an aluminum casting had daubed-on aluminum paint....

I'm familiar with Gasolia but I wasn't able to identify which product could be used this way. The red joint compound is described as a "red varnish" but one would think it was likely to be too thick to use to paint the inside of a crankcase. I wonder if it can be thinned out and used as a paint. I may experiment with it as I'm buying some for the screwed in core plugs in any case. I was planning to use glyptal, which appears to be a similar product though designed for the inside of crank cases. And yes, as trimacar says, the case was painted with aluminum paint. In fact, the two aluminum brass car crankcases I have in the shop right now both are. This was the standard procedure at the time.

The red Gasoila is what can be used to "paint" the inside of crank cases, Glyptal is a good product too for the same purpose...

You could try POR 15 Marine clean.

It certainly cleans any oily junk, stale gas etc out of old gas tanks when you are preparing them for recoating on the inside.

It is a very good degreaser that doesn't leave any residue. Diluted with hot water it really works

http://www.por15.com/POR-15-Cleaner-Degreaser_p_14.html

Ultrasonic cleaning would be the answer if you had a cleaner big enough. Engine rebuilders used to have a "cold tank" for aluminum engines, don't know what it used for a cleaner.

Just make darn sure the dip tank is compatible with aluminum...some tanks will give you an aluminum scrap piece...and even dip tanks don't address the major issue with early aluminum castings, they are saturated with oil and it's very difficult to remove that .....

Just make darn sure the dip tank is compatible with aluminum...some tanks will give you an aluminum scrap piece...and even dip tanks don't address the major issue with early aluminum castings, they are saturated with oil and it's very difficult to remove that .....

I couldn't agree more, which is why I'm staying away from the standard solvents, lye etc. I'm trying an experiment using washing soda & detergent in a heated tank. The water will be circulated at a fairly fast rate using a submersible pump so I'm hoping that the oil will be precipitated out of the metal, emulsified by the detergent and carried away by the water. We'll see. If it works I'll be glad to share the results.

jp

I once designed and built a cooker for apple slices, robust construction to allow pulling a serious vacuum thus pulling air out of the fruit, then hit it with high pressure steam to replace air pockets with water ( condensed steam)....

That's why the vacuum degreasing worked so well, the vacuum pulled the oil out of the pores of the aluminum, leaving a darn near virgin metal.....surely there's someone out there doing vacuum degreasing??

There are places in RI that do vacuum degreasing. Google "vacuum degreasing" + RI to find one near you. Wait. In RI everything is near you! Here is one:

http://www.impco-inc.com/services/kleenpartz-cleaning-and-degreasing

With our increased capability and capacity, Impco can now offer full vapor degreasing services to others aside from our regular customers. That means engine rebuilders can now utilize our degreasing to clean engine parts prior to assembly, thus eliminating a time-consuming and expensive task. Platers can use our vapor degreasing to remove masking compounds from parts surfaces after plating. Fastener makers can easily and economically clean deep draw products. Tube benders can now utilize solvent cleaning to remove the heavy lubricants used in making their products. Stampers can remove the oils without fear of oxidation. Others who need vapor cleaning can now use our services

Interesting. The used to be on Valley Street in Providence, literally across the street from my print shop. I used them years ago to seal a RR Phantom I head but hadn't thought of them for a long time and didn't think to search on "vapor degreasing". I will likely save this until all the machine work is done and get it thoroughly cleaned just before reassembly.

And... near is a relative thing. Some places, like Newport, are not all that far geographically but very tedious to get to in the summer. I generally stay out of the southern half of the state during the tourist season.

Thanks,

Joe P

Once cleaned I was going to suggest coating the inside with Glyptal as well. Dupont makes a nice Alum for the exterior.

As mentioned above, once cleaned the aluminum crankcase will likely leak like a sponge. I've had the experience of a weeping crankcase. I just couldn't understand HOW the starter was leaking oil. Removed the starter and the area of the crankcase hidden behind the starter was soaked with oil. I tried several cleanings and it still soaked through and dripped oil with each trip I took the car on.

I ended up dropping the oil pan, and using an aviation gas tank sealer on the inside of the crankcase to seal the porous area. The aviation sealer is meant to be used on aluminum that cannot be completely cleaned of oils, like the inside of a 'wet wing' fuel tank.

The #5 connecting rod was tossing oil against the porous spot on this engine, causing it to leak through.

I've used Glyptol on fresh rebuilt engines since. With a freshly hot-washed crankcase, the glyptol works well.

GLong

The company that Dwight Romberger pointed out, Impco (in East Providence RI) impregnates castings with some sort of resin under extremely high pressure, which is why they have elaborate vapor degreasing equipment. Many years ago the late Frank Cooke (Technical VP of the RROC) recommended them to treat the aluminum head of a Phantom I. I'd forgotten all about them until reminded by Dwight. My current plan is to clean the crankcase as best I can with a hot tank using washing soda and detergent. I'll then do the machining... making inserts, bearings, replacing studs etc. When the case is mechanically ready for reassembly, I'll have Impco degrease it and have it impregnated, after which I can paint the inside and outside. I think it will probably be as tight as can be hoped for.

Fortunately, shipping the case isn't a problem since they are only about 40 minutes from my shop.

I need to figure out how to get my 1910 Buick crankcase to them! Hate to ship it...but that sure sounds like the way to go on aluminum...

If you know anyone coming this way I'd pick it up from them or they could leave it at my shop and I could get it over to them for you.

jp

Thanks, let me think on it.....