Cleaning out water jackets, with block outside car.

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Slantsix64

Slantsix64

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Hey guys wanted to know what I could use to clean out my water jackets in my block, I already have flushed out all the gunk and rust sludge,

I wanted to put some new freeze plugs and leave the plug at the highest point on the back of the block open and run some CLR in the blocks water jackets and let it sit for a couple days and flush it out again. The reason is I don’t want to disassemble my engine which has low miles and is a runner, just want to give it a good flush!

Would CLR work?

The heads are already off and they will get hot tanked after the porting is done.
 
Power washer through each hole with the freeze plugs out and water pump off the engine.

You'd be surprised at the pile of sand that will come out. A lot of the sand has been there since the engine was first cast.
 
Princess Valiant said:
Power washer through each hole with the freeze plugs out and water pump off the engine.

You'd be surprised at the pile of sand that will come out. A lot of the sand has been there since the engine was first cast.
Click to expand...
Yeah i know that’s what I did and man was it nasty, I wanted to see if I could fill it up and leave some chemical in it over night to help clean out what’s left on the walls
 
Princess Valiant said:
Power washer through each hole with the freeze plugs out and water pump off the engine.

You'd be surprised at the pile of sand that will come out. A lot of the sand has been there since the engine was first cast.
Click to expand...
Don't forget to remove the two threaded drain plugs at the very bottom of the block; one on each side. I don't know what they are called.
 
Muriatic acid works REAL good, but you sure have to be careful with it.
 
Take a coat hanger and bend it about the shape of the cylinders and work it around the cylinders while blasting water in.
I put the block on a sheet of plywood so I can rotate it in all directions and stand it on both ends blasting in every hold and working the coat hanger into every crevasse.


Alan
 
Wear a raincoat, galoshes, and a sailor's hat cause you'll be slinging water everywhere! If you wear glasses get windshield wipers for them too!!!
 
Slantsix64 said:
Hey guys wanted to know what I could use to clean out my water jackets in my block, I already have flushed out all the gunk and rust sludge,

I wanted to put some new freeze plugs and leave the plug at the highest point on the back of the block open and run some CLR in the blocks water jackets and let it sit for a couple days and flush it out again. The reason is I don’t want to disassemble my engine which has low miles and is a runner, just want to give it a good flush!

Would CLR work?

The heads are already off and they will get hot tanked after the porting is done.
Click to expand...

I used vinegar and let it soak for 24 hours.
Then about 30 inches of brake tubing with a tight 90 on the end adapted to a water hose and then flushed through the front plugs openings with all the plugs out.
It got up down and between the cylinders.

While it was soaking it sounded like a coffee maker perking.
 
Princess Valiant said:
Power washer through each hole with the freeze plugs out and water pump off the engine.

You'd be surprised at the pile of sand that will come out. A lot of the sand has been there since the engine was first cast.
Click to expand...


And wear some rain gear when using the pressure washer lol.


Edit: treed by post 7. HARD.
 
TrailBeast said:
I used vinegar and let it soak for 24 hours.
Then about 30 inches of brake tubing with a tight 90 on the end adapted to a water hose and then flushed through the front plugs openings with all the plugs out.
It got up down and between the cylinders.

While it was soaking it sounded like a coffee maker perking.
Click to expand...
Trialbeast, did you use white vinegar? Do I have to spray it down with wd40 after?
 
Mine were horrible! I just put plugs in, tilted the engine on the stand and filled it with Derusto, I think. Let it sit a day and tilted to the other side and refilled. Rinsed it out and clean as new.
Wish I save more pics, but here's one.
b3.jpg
 
Slantsix64 said:
Trialbeast, did you use white vinegar? Do I have to spray it down with wd40 after?
Click to expand...

I wouldn’t use anything oily inside the cooling system, as it will coat the entire system possibly causing a loss of heat transfer.

Also, I have used muriatic acid on things before but it’s very dangerous and the fumes can kill you.
I would only use it if I could stay completely away from it while it cooked.

White vinegar is fine, just takes longer, but safe.
I would give a block a couple of days soak, then rinse with water.
 
TrailBeast said:
I wouldn’t use anything oily inside the cooling system, as it will coat the entire system possibly causing a loss of heat transfer.

Also, I have used muriatic acid on things before but it’s very dangerous and the fumes can kill you.
I would only use it if I could stay completely away from it while it cooked.

White vinegar is fine, just takes longer, but safe.
I would give a block a couple of days soak, then rinse with water.
Click to expand...
Vinegar it is! Hopefully my puppy doesn’t get annoyed!

IMG_2620.jpeg
 
Brooks James said:
Get a rifle cleaning kit , use muriatic acid
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I can agree that Muratic would work well, but how can one carefully do it? I used Muratic acid once to clean out a gas tank before treating it with an Eastwood gas tank treating kit. It was easy to handle / manipulate, so there was no spillage, slopping or spray anyplace I didn't want it. However, as many people have attested (and I know because I have done it), when you do the inside of an engine, it gets real messy. I think it would be difficult not to slop and spray acid everywhere; not sure if it would be worth the risk.
 
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If you DO NOT have experience using acids and alkalis, DO NOT endanger yourself, loved ones or pets. Use any of the non toxic solutions as suggested above. Acids and alkalis can harm or kill quickly! We used to store chlorine tablets for our pool in a shed attached to the back of the garage. A neighbor asked if he could borrow a few until he could get to the supply store because he was out. He did not reseal the bucket and being humid in Texas, moisture got into the bucket. I went out a few days later to get some tablets for our pool. When I took the lid off the bucket, the chlorine gas hit me in the face. I passed out, but luckily my wife saw what happened and called 911. After being checked out at the emergency room, I was told I was lucky that it didn't fry my respiratory system. It was a mistake on the neighbors part for not resealing the container and a mistake on my part as well, for not checking. We all do dumb things and some of use survive and learn our lesson. Some of us don't, be careful!
 
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