Alternator cleaning

MikeT · Unread post by **MikeT** » 13 Nov 2009, 12:35

I have a spare alternator that I'd like to clean as it's been drenched in engine oil. What, if any cleansing solutions are safe to use. I think Jim used contact cleaner on his LHM soaked alternator - would that clean off engine oil ok? Any other alternatives?

Unread post by **Old-Guy** » 13 Nov 2009, 14:49

One of the best ways to remove every trace of oil from almost anything is a good soak in hot water with plenty of ordinary washing detergent (we used to reckon Daz was the best for this) followed by a thorough hot rinse and (blow) dry.

Obviously, the item in question should be resistant to both water and detergents. Having said that, I've cleaned engine blocks and cylinder heads like this, the trick is to get some WD40 on all the machined surfaces immediately it comes out of the wash - then worry about getting it dry.

As the front and rear bearings might lose too much lubricant, and the electronics would need to be very thoroughly dried, I would remove the two end plates and just wash the rotor and the cylindrical case complete with field coils - the two things most difficult to get properly clean and whose 'varnish' is vulnerable to solvent attack.

handyman · Unread post by **handyman** » 13 Nov 2009, 17:44

If you try a good quality motor factors there is a special cleaner used to clean all types of automotive electrical equipment. It is made by the same company that makes Gunk. You can apply it by spray and it will remove all the baked on crud and then leave it to air dry. It does not attack sealants or insulation, so any windings and contacts will be safe. Not cheap but it does the job and will get the unit looking like new. If I get to the workshop over the weekend, I'll look up the name for you and post it up here.

Contrary to Old Guys recommendation, NEVER use WD40 or any similar sprays as they contain silicates that form an electrically resistant film on anything they come into contact with. WD40 is also known to attack many types of plastic and cause them to fail by decay. If you want to use a preservative spray, use contact or switch cleaner, which does contain electrically conducting cleaners and preservatives. I usually buy mine at my local electrical wholesaler, but not all factors stock it.

Handyman

Unread post by **Old-Guy** » 13 Nov 2009, 17:59

Sorry, I should have made it clearer that my recommendation of using WD40 was for ferrous machined surfaces on head and blocks ONLY - otherwise a film of rust forms very quickly.

addo · Unread post by **addo** » 13 Nov 2009, 19:10

You can buy a cleaning spray for Paslode nail guns that is pretty sensitive in terms of removing carbon yet not eroding insulation varnish - it's less aggressive than methanol/acetone based throttle body cleaners.

Cheers, Adam.

MikeT · Unread post by **MikeT** » 13 Nov 2009, 20:51

Okay, if contact will do engine oil, I'll give that a try first. Thanks all.