Engine block cleaning solution

[John kuehn]

I have a 25 block I bought years ago that has really good babbitt. It has a coat of rust on it and not all rusted and pitted up. It’s been in my shop and out of the weather.

This might be my last engine rebuild and I have some transmissions, parts and etc to do it.



I have some large heavy poly feed tubs I can submerse it in.
So the question is what’s the best soaking solution to use that won’t hurt the babbitt.

I’ve heard of white vinegar, evaporust, and others. So what’s the best that’s fairly cheap and easy to obtain. Thanks Forum!

[Les Schubert]

I have used farm grade molasses with success

[Art M]

Before spending a lot of time cleaning the block, make sure that you have a crankshaft that fits the babbitt diameters and the thrust surfaces. And make sure the babbit is actually in good condition. Condition fools a lot of people.

Art Mirtes

[Erik Johnson]

I have used 5 to 1 water and molasses solution for small items but note that it can cause cratering if you leave the object in the solution too long.

HOWEVER - I saw this YouTube video of a fellow who cleaned-up an engine block using Evaporust and water displacement. This allows you to use a minimum amount of Evaporust. Be sure to watch in the entire video.

https://www.youtube.com/watch?v=LH5GwVC6zsk

If you do use Evaporust, remove all grease, oil and dirt first. Don't know what Evaporust or similar products like Metal Rescue does to babbitt. Also, in case you have never used Evaporust, you can use it over and over again until its effectiveness is depleted so, when you are done using it, pour it back into the bottle until you use it again.

[Dashpot24]

If the outside of the block is rusty, I think you could tape off the bearing areas, put the block on risers in the pan, and apply a product such as Naval Jelly to the exterior. It is just hydrochloric acid with a thickener, so it would stay on the vertical surfaces of the block. Then, you could powerwash t or scrub down the whole block with hot water and rinse it down really well.
I don't think you should immerse the entire block in acid. Any acid will solubolize yellow metals which it contacts. According to Wikipedia the Ford Babbitt contains 7% copper. Evapo-rust is simply tannic acid with a surfactant package. I have used 4% common white vinegar for hand tools that are really badly rusted, but it takes a long time and would not be suitable for this application.
Otherwise, would it work to remove the rust mechanically? with a 4-1/2 angle grinder equiped with a nylon abrasive cup brush? I think they sell those at harbor freight.
Without a picture, it is hard to understand how rusty this block really is.

[jiminbartow]

Being that the block is cast iron, be very careful about using any type of acidic corrosive cleaner as it will attack both the rust and the cast iron, quickly dissolving the cast iron. Be sure to test the solution you plan to use on a small area before doing the whole thing. If the test drop turns white and starts to bubble, be very careful. Neutralize any test area with baking soda and water. “Naval Jelly” is a rather mild, slow working acidic cleaner that might do the job, but again, test first and be cautious. Jim Patrick

[ThreePedalTapDancer]

[Erik Johnson]

In the past, I have Googled in vain to try to find out what the actual chemical make-up of Evaporust is. In my opinion, it's something that one should be able to make themselves if they knew what the ingredients were.

There are a lot of opinions of what the Evaporust solution actually is, but nobody is quite sure.

Evaporust doesn't hurt paint, nickel plating or chrome plating. However, it does remove galvanized plating.

It used to be a bargain when I bought it by the gallon at Harbor Freight with a 20% off coupon. Unfortunately, it has doubled in price in the last five years, at least where I live.

I believe Metal Rescue is the same as Evaporust. I bought two gallons of Metal Rescue at a deep discount at Menards a few years ago but haven't needed to open a bottle yet as I am still have a gallon of Evaporust that is weak but not yet fully exhausted (I pour it back into the bottle after each session).

About 15 years ago, there was a rust removal business here in MInneapolis that catered to auto restorers. They had large open tanks full of Evaporust in which they could soak car frames, fenders and other large parts. They also had a system where the large part would sit in a tray and it would be continuously bathed in a shower of Evaporust. I don't know if they are still in business. They used to exhibit at the "Back to the 50s" street rod event at the Minnesota State Fairgrounds.

[ThreePedalTapDancer]

Best guess of Evaporust ingredients from a science blog: https://www.thenakedscientists.com/foru ... #msg583069

“It appears that this product is composed of three compounds: water, a chelating agent and a detergent. Unfortunately, they are keeping the formulation as a proprietary trade secret. Based on the sds, it appears that the product is slightly acidic (6 <pH <7), and is fairly non-toxic, and only produces CO, CO2 and H2O during combustion. (see here: https://images.homedepot-static.com/cat ... a09231.pdf )

I would guess that the chelating agent is a partially deprotonated (self-buffering) poly-acid (for example, a mix of dibasic and tribasic citrate would buffer at a pH of about 6.4, and would likely be an excellent chelating agent for iron, and would be edible).

The detergent could be something like choline (cationic) or a deprotonated fatty acid, like laurate (anionic) or betaine (neutral, zwitterionic).”

[speedytinc]

If your issue is external rust, I would clean it up with wire wheels.
Thats how I clean a block of rust & old paint.
Clean the large areas with a makita angle grinder with a twisted cup wire wheel.
(Be careful, this tool will take a lot of meat off your hand if it gets away from you.)
Use a small air die grinder with smaller wire wheels to get into tighter areas.
Use scorch pads to get into the crevasses. The metal doesnt need to be bright silver grey, just clean enough to take paint.
I prime all components with flat black rustoleum & finish with semi gloss black after the motor is assembled.

[John Codman]

Believe it or not, pickle juice is a gentle solvent. I used it to clean up the ball valve in my Holley NH. I admit to being a bit skeptical when I was told that it would work, but it did.

[Erik Johnson]

I love Evaporust because it doesn't hurt paint or chrome or nickel plating.

I just wish I could make a solution of it myself instead of buying it off the shelf.

[Erik Johnson]

RE: pickle juice

Mixing vinegar and salt produces hydrochloric acid.

[Craig Leach]

Hi John,
Several years ago we built a skinny block Chevy (we as in my15 year old granddaughter and I) One cylinder had a deep score in it from a
broken ring so the engine had to be bored. The machine shop used what they called a industrial dish washer to clean the block. They
insisted that the cam bearings had to be replaced because the process left any bearing etched and un useable. He insisted that anything
not petroleum based would damage the Babbitt in the bearings? I would suggest that anything you use you test it with a old rod or main
cap to make sure it doesn't attack the Babbitt. If you have to do the inside of the block the wire brush idea will take forever and one slip
up can destroy a bearing. The last two I have done where the scraper, wire brush & solvent. Thankfully there was no rust on the inside.
Please keep us updated on your progress.

There is some products on the market that claim to convert rust to a paintable surface. They seem to work good on light rust has anyone
tried them on a engine?
Craig.

[John kuehn]

Sounds like the farm molasses will work. It’s probably best to use a 1 to 5 or less ratio? I’ll check it closely to how it’s turning out. So a weaker solution will take a little longer but will still work pretty good?
Thanks forum!

[Dennis_Brown]

Will using sodium bisolfate and water solution and a battery charger negative terminal connected to the block and the positive lead hooked to a sacrificial piece of iron and the 2 items separated from each other harm the babbit?
I know it will remove rust and testing it on an old connecting rod with babbitt would tell for sure. I know it eats brass.
Sodium bisolfate is cheap, I get itat Walmart to use in a pool.
I have cleaned up hubs and other rusty parts with it and it works.
One good tip if you use it. I used a 2 foot piece of rebar as the sacrificial piece but I took a piece of 1 inch plastic pipe and drilled 3/8 holes in it to let the solution thru so it would not touch what I was deducting and had 14 gage solid copper wire hooked to each piece.
I left it overnight and checked it the next day. Leave it until you are satisfied. If you have the negative lead hooked to what you are deducting it will not eat their on away. Rinse it well when you remove and blow it dry.. it will start to get lighter surface rust quickly so be able to paint it , spray it with a rust inhibitor ,coat it with oil or grease or whatever you choose.

[Craig Leach]

Electrolysis will attack the softest metal first and I'm afraid Babbitt is the softest metal in this equation.
I have a plastic horse trough set aside for doing this on large parts using solar to generate power but I'm not finished with the set
up yet.
Craig.

[Vonau]

I just cleaned my block of rust. I used many different rotating wire brushes to do this. Took some time and the valve area was complex.
My problem now is the cooling water channels. Limescale has built up quite thickly (picture) and I still don't have a solution. Does anyone have an idea how to get rid of this?

greetings from Switzerland

[John kuehn]

Some have used an old speedometer cable chucked up in a cordless drill. The flexible cable helps in loosening the scale.

[Les Schubert]

Vinegar works fairly good for removing scale without attacking the metal.

[jiminbartow]

Anyone ever try CLR (stands for Calcium, Lime & Rust). Jim Patrick

[Craig Leach]

Hi Beat,
Nice job cleaning up that block. I use a Zep product ( calcium rust & lime remover ) very much like CLR but cheaper & better. I don't
know if they are available where you live. I set the block up in a cement mixing tub, make sure its level, put the water outlet on upside
down with apiece of hose on it and fill it up to almost the top. Try not to get it on the Babbitt. And let it set. then drain it ( you can use
it over again ) then flush well with clean water. A pressure washer helps if you have one. if not satisfied repeat. you can do the same
with the head but its harder to get level. There are stronger solutions but have found this to work good. The speedo cable idea will help.
I once used it on a skinny block Chevy to clean out the EGR port while on the engine. Speedo cable is not very easy to find now days if
I find any good cable I save it to make speedo cables out of.
Craig.

[TFan]

Look for an old junk weed wacker and get the cable out from it. I got three pieces out of one cable cut them with a grinding wheel or a Dremel type tool, I put a piece of tubing about 1/4'' inch long over the cable about 2 inches back from the tip and staked it in place then I splayed out the end of the cable. When chucked in a drill this makes an excellent rotary wire brush. Jim

[Craig Leach]

Hi Jim,
Great idea that should be easy to come up with. And much more ridged.
Craig.

[TFan]

I was wrong about staking the tube piece I actually put a little weld to it. Here are some pics. The one is quite well used. the ones that aren't splayed are good for getting into the smaller openings on the head and block. Jim

[Vonau]

Hi

Thank you for all the good advice.
I've tried different wire ropes. But the lime is very hard and I don't stand a chance with that alone. Motor has stood still for about 70 years).

As an experiment, I also placed some chunks of lime in phosphoric acid. Lime was completely dissolved. But I see that would damage the casting. So it's out of the question.

I see I can't buy CLR from us. It doesn't look any better with Zep products.

I'm currently trying my wife's vinegar cleaner (apple cider vinegar). Put in some chunks of lime from the engine. Let's see how it looks until tomorrow.

greetings from Switzerland

[Gen3AntiqueAuto]

If anyone is still interested in this topic I just spent a week testing a product from WD40 on a boat anchor I am converting back into a transmission for the 27 engine that no one wants to buy.

Here's the link to the video:

https://youtu.be/ikyCtX1-lw4

[Adam]

I use an ultrasonic parts cleaner, then medium glass bead. If you don’t have an ultrasonic cleaner, the plain old parts washer works good too. Just a little more work.

[Quickm007]

Hi Dear John, all the tips above but add this way by Steve Jeff work really well too.
https://www.youtube.com/watch?v=TJ3nkPm87X0
https://www.youtube.com/watch?v=RnOZ2MZt5FY&t=27s

[Craig Leach]

Hi Guys,
I know this thread was concering rust & babbitt and you can remove rust with acidic solutions but they damage babbitt so you would have to
controled it so that it did not contact the babbitt. Caked on Grease is also a issue when cleaning aparts. I was just over at the neighbors and
he was cleaning VW cases with a small steam cleaner that he picked up on Amazon for around $150 I was impressed that it would clean baked
on grease from VW cases ( and grease gets caked on air cooled engines) Has anyone tried one of these small steam cleaners made by McCulloch
Steam Power MC 1275. Sorry I dont have a grandkid handy to show me how to attach the pic I sent to every damn file I have on my computer!
Craig.