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What should I use to clean up a motor?

2188 Views 10 Replies 9 Participants Last post by  beck
I'm taking a 4bt out of a P-30 truck to use for a pickup swap. The exhaust manifold to turbo gasket is shot. The whole side of the block including the alternator is black from the exhaust. What would work best to clean this up so I can repaint the motor before installing it?
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If there is a Lowes near by look for "KrudKutter" It is strong enough to remove wax from floors. If not just use one of the normal engine cleaners like Gunk or what ever is available locally. Use a parts cleaning brush and wear eye protection and rubber gloves. Keep the rinse water out of the engine.
I would probably say carb and choke cleaner would be best on the soot, then wire brush any surface rust. If you have access to a steam cleaner I would steam clean it and use a little Engine Brite, just remove the starter and use towels and duct tape them in to any of the places you don't want water...
The motor is still together so it should be pretty well sealed up. I will naturally have to watch the air cleaner and the blown turbo gasket. I'm new to the diesels. Is there anything else that can't get wet?
I take my engines to Cummins In Plattsburgh NY and have them steam cleaned. This is true steam, not hot water. After soaking in a solvent for a few minutes they follow up with steam. When complete she is absolutely clean and dry. Prior to paint, I take a wire brush and get any loose paint off that lifted with the steam. I then shoot PPG, MP-170 Epoxy Primer followed by Cummins Beige.

Gunk works well; I use Marine Clean (made by the POR15 people) a lot, with good results. For minor dirt and grime Simple green has always worked well for me.
Throw some copper RTV on that manifold instead of a gasket. Works great.
clean er up

As long as you keep it away from aluminum brackets, etc, OVEN OFF works great! Just keep it off shiney parts or it etches them. Also tried the grease lightning from lowes, and seamed to work better that the simple green and cost less....My 2 cents...
I tried the chemial engine cleaners, smells bad, hardly does the job.. I second the steam cleaner idea. But I use a traditional "de greaser" Castrol brand, diluted with water, brushes, etc. Takes a long time but works.. The problem with the chemical cleaners (gunk, etc) is the fumes and you still have to scrub.. So use something milder IMO that works as well..

with 2600-2800 pressure. Blow the grease and crud off. I have used both commercial car-wash and my own pressure washer.

Once clean, I use @ 300-400 grit to make paint adhere. If paint is flaking or non-adhering, I steel brush it all off and primer. On my 4BTA, it suffered from West VA salting, so I cleaned the loose-rust stuff off, painted with POR-15, and gave it Cummins Beige just before dry. Did not POR15 the whole engine, just the rusted areas, non-rusted got only scuffing for paint adhere.

While there are many ways to ultimately get clean, the above method was targeted to an engine that was not to be disassembled.

Well I got the motor pretty clean this am. It is still in the P30 chassis so I'm sure I missed some spots. I sprayed it down with a can of penetrating oil last night and let it soak a few hours. Then I hit it again later with another coat. This a.m. I uncovered it and gave it another quick shot as I was setting up my pressure washer. I washed it down with the pressure washer. (I hooked up to the hot water faucet. When I was done my wife tried to take a shower. No hot water for her, but now I'm in it!) Then I sprayed it a few times with some solvent cleaner (a lot like kerosene) and let that soak before spraying it agian. In an attempt to clean all the oil off I mixed up 3/4 Mr. Clean and 1/4 dishwashing soap. Then I cut that in half with water. I soaked it again and then sprayed that off. I found out it is Cummins beige, at least on one side. The exhaust leak still has one side black. All the dirty, oily grunge is off though.
In my search for soapI came across Krud Kutter Rust Remover. The only part of the motor that has any rust is the front. I was wondering if anyone has tried this stuff??
I also came across products that are paint preps - gloss removers - like liquid sandpaper. Anybody tried this?
It was recomended to sand the motor (I normally use Scotch Brite pads)where needed. How do you get your hands in those little places?
I have done the motor clean ups before for paint but on a gas motor. Those are easier to get to things. No injector pumps or turbos. Normally on a gas motor I pull the carb and intake and do those seperate. Then pull the exhaust manifolds and the whole side of the block is accessable. I don't want to pull this motor apart.
While OUTSIDE :nuke: I have had some luck spraying other motors down with ether :rasta: to get the last of the oil off before painting. If there is a pocket of oil, or some stuck in a gasket, it will flow down the block making you do more cleanup.
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