14 replies to this topic

[oliver122]

hey guys , so i want give my engine a clean , its out the car atm so its the perfect time , but its corroded , so was wondering whats the best way , i had a wire brush on a drill and had a go on the gearbox , it did clean it up but looked liek it scratched it , so didnt really want do the clutch casing that way , any help would be great

[tractor]

Chrome plating would be nice like on the front vizzards book



Trac

[Barman]

POR 15

Marine clean >>> Metal prepare

[xrocketengineer]

My engine looks like this. The gear box came from Guess-works but the air conditioning compressor, the clutch cover, the distributor and the transfer gear case were all cleaned with Loctite's Aluminum Jelly and a lot of hand brushing with brass brushes.



http://www.loctiteproducts.com/p/s_trmt_alum/overview/Loctite-Aluminum-Jelly.htm

[purple_fly06]

If you just want to clean it, then some engine degreaser sprayed on and then steam cleaned off.

[Tamworthbay]

WD40 and very fine wire wool is one of the worlds best kept secrets. It works miracles on lightly corroded ally.

[tiger99]

This is rather interesting, so far. I would like to know how anyone would actually attempt to keep it clean, when the car is in use. I had a nice, clean one once upon a time, and I tried, a few times, to keep it that way, but was always beaten by the combined effects of minor oil leaks, road dirt etc. The casing, as cast, has a surface which is rather good at picking up dirt. I suppose that polishing out the roughness, a rather big job, would help.

[firefox]

I jet washed mine came up a treat, the Wok i spray painted after using wire wool on it, can just wipe it clean now

[dklawson]

I have used a combination of several of the suggestions above.

• Start with a good degreaser to wash away the heavy oils, road dirt, and grime. Use an old paint brush or similar with stiff bristles to work the degreaser into the nooks and crannies.
• Follow the degreaser with a mild caustic cleaner (If you use the POR Marine Clean above, dilute it with water first. It is strong caustic that will attack aluminum). You can use spray oven cleaner (if it says it is caustic) but like the Marine Clean you need to keep an eye on it as it is often a strong caustic.
• Scrub the caustic in with a stiff bristle brush, keep working it and then rinse it off with lots of clean water.
• Once you have taken the box to that point, use something like aluminum wheel cleaner from the auto parts store and scrub it into the gearbox. You can use the stiff brush again but at this point I typically switch to a small detail brush with stainless steel bristles.
• Work the wheel cleaner in quickly and be sure to use the brush a lot. Don't allow the cleaner to sit idle or you are likely to get a blotchy appearance. Work quickly with the brush then rinse the wheel cleaner off with lots of clean water.
• Hit any isolated spots individually with the wheel cleaner and detail brush then rinse again.
• Use compressed air to blow the casing dry. If you allow it to dry slowly you may get blotches again.

Once the gearbox is dry, apply a clear enamel over the box to protect it. There are some automotive clear coats designed just for bare metal and I have had good results with them.

[JustSteve]

I use 'ally-clean' off ebay for about everything, 28 quids for 5 litres. It's an acid cleaner so must be used only on suitable surfaces, but it removes oxides from alloys and steels, aswell as removing anodized plating. I'm going to use this on my gearbox and casing.

So far I've used it on rusty hubcaps, corroding wheels, corroding bike frame, various other bike parts etc.

[dklawson]

The "Ally Clean" is probably some formulation of phosphoric acid. Phosphoric acid is common in most aluminum cleaners and rust removers (and the POR Metal Ready mentioned previously). With aluminum, other compounds are often added to the acid and the concentration adjusted differently than what is used on steel/iron. Phosphoric acid is also likely to be the active ingredient in the wheel cleaners I have used but I don't have any to check at the moment. It is a good chemical to use in cleaning and rust treatment. However, don't allow it to dry on a surface you are preparing. Keep the surface moist until you are done with the cleaning process then rinse and dry quickly. This is true for aluminum and steel/iron.

[JustSteve]

However, don't allow it to dry on a surface you are preparing. Keep the surface moist until you are done with the cleaning process then rinse and dry quickly.

Why is this dklawson? I noticed that it seemed, what looked like the corrosion i had just removed, had come back 10 times worse inside a tube I hadn't washed out.

[dklawson]

The acid etches the surface. The longer you leave it on the surface and keep it wet the longer the acid works (a deeper etch with darker color to it). As it dries, the acid cannot suspend the corrosion products it dissolved and they will deposit back on the surface AND trap a bit of acid on the surface at the same time. The results can be loose chalky deposits with unpleasant discoloration of the surrounding surfaces.

Phosphoric acid is commonly used on bodywork for panel preparation prior to painting. If the acid is allowed to dry on those surfaces the resulting film left behind is loose and does not allow the paint/primer to bond to the panel. Keeping the panel wet followed by quick rinsing and drying prevents that. Many people "freak out" when they rinse and dry the panel because flash rust is almost certain to form no matter how quickly you dry the panel. That flash rust is VERY loose on the panel and is easily removed by wiping down with prep solvent. It is nothing to worry about as long as you don't leave the panel sitting unpainted for days... which would allow real rust to develop again.

[Tamworthbay]

I use 'ally-clean' off ebay for about everything, 28 quids for 5 litres. It's an acid cleaner so must be used only on suitable surfaces, but it removes oxides from alloys and steels, aswell as removing anodized plating. I'm going to use this on my gearbox and casing.

So far I've used it on rusty hubcaps, corroding wheels, corroding bike frame, various other bike parts etc.

Which one do you buy? A lot seem to just be fancy soaps for cleaning dirty not oxidised alloy. Be interesting to compare it to my old fave of WD40 and scotchbrite pads.

[JustSteve]

I use 'ally-clean' off ebay for about everything, 28 quids for 5 litres. It's an acid cleaner so must be used only on suitable surfaces, but it removes oxides from alloys and steels, aswell as removing anodized plating. I'm going to use this on my gearbox and casing.

So far I've used it on rusty hubcaps, corroding wheels, corroding bike frame, various other bike parts etc.

Which one do you buy? A lot seem to just be fancy soaps for cleaning dirty not oxidised alloy. Be interesting to compare it to my old fave of WD40 and scotchbrite pads.

http://www.ebay.co.u...984.m1439.l2648

this stuff. I never expected it to take the anodising off, but I found out when I got some on my push bikes handlebars.

It suggests diluting 15 parts water as well, for general cleaning, but I tend to use it a lot stronger than that, but re-use it