Easy Engine Sludge Removal
 

Removing Engine Sludge. When dismantling an old or used engine, to be repaired or worked on, the accumulated sludge and combustion by products inside the engine are always a problem to clean at home.
Most solvents and cleaning products do not work well and it is a laborious uninviting job to get the professional result most of us would like.

What works for me:
Home Oven cleaner spray, available at your supermarket.
Be sure to observe ALL the safety precautions listed on the can. Best to use outdoors or in a well ventilated area and wearing gloves and goggles.
I am in no way responsible for your safety of how you may choose to use these products.

There are generally two types available, aluminum safe and non-aluminum safe. The non-aluminum safe will dull polished aluminum but not much else in the short length of the term used and is generally more potent.

How to use: Leave the engine mostly assembled in sub-assemblies i.e. Short engine, cylinder heads complete etc.

Spray the oven cleaner everywhere there is sludge or dirt, in the crankcase, cylinder head ports and valve springs.
Leave for 20-30 minutes and hose of with water. Dry the parts with compressed air and leave in the sun. Remove the crankshaft and camshaft if installed, dry and inhibit all parts with corrosion preventative. For heavily soiled engines, a few applications may be necessary. Most engines will require 2-3 cans of spray. Good luck and enjoy.

Re: Easy Engine Sludge Removal
 

It helps to remove as much sludge manually before spraying on the oven cleaner. I use an old putty knife and a plastic spatula. The warmer the block the faster goes the process, so I never bother unless the temperature is at least 70 degrees. Observe Ian's safety precautions and wear old clothes.

Re: Easy Engine Sludge Removal
 

I don't know about "aluminum-safe" or not, but I've found that there are two flavors of oven cleaner: old fashioned stuff (aka "extra strength" or "industrial") that is based upon lye (sodium hydroxide) and the newer "fumeless" or "fume free" that is based upon butoxyethanol compounds. I've tried both for grunge removal. The latter (fume free) doesn't work at all for me, and the former (lye based) works great. Scrape off as much grunge as you can, as ursus suggests, spray the stuff on, spray it again, then spray it again. Let it sit for a half hour or so, scrub with a wire brush until you get a nice disgusting brown foam, hose it off, and repeat if necessary. All the safety precautions apply.

I find I use a full large spray can or two for a short block. Best $10 spent.

Re: Easy Engine Sludge Removal
 

Is there any good reason I can't see the poll question?

Re: Easy Engine Sludge Removal
 

Lower right corner, it works

Re: Easy Engine Sludge Removal
 

The poll question is as in the contence of #1. Like, works, don't like or does not work.
The reason for the poll is to share with those that were not aware and did not know of what is being suggested in #1. All I am asking is for he voting to be honest and straight so that folks will be able to make up their own minds of what alternate methods are available to them for a particular situation. Most of the comments have been positive and I have learned that this particular method does not work in cold weather (<70 f) as I live in a hot climate and have never experienced this. So to me when URSUS & JAJAY make further helpful remarks, from experience, I am satisfied that somewhere it has helped someone.

Re: Easy Engine Sludge Removal
 

Oven cleaner can cause caustic embrittlement....If that is a concern down the road... It might be for things like exhaust manifolds, or a block that is designed with some areas a little bit weak.

Re: Easy Engine Sludge Removal
 

buy your oven cleaner at the dollar store- much cheaper..................


I use it to clean showers at rentals.

Re: Easy Engine Sludge Removal
 

I beleive that this is a bit far fetched as there is no superheated steam involved and further to that, hot caustic tanks are the norm in the engine rebuild industry for cleaning.