42 year rust, can i save it?

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GreekDart

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Hello everyone, my Dart is pulling me deeper and deeper .... This is my first car project ever. I took out the rusted freeze plugs (as Mike69cuda suggested) after removing the manifold and the rust seems to be overwhelming to my eyes. Is there a way to get rid of all this rust without taking the engine out? Also behind the 1st freeze plug, theree seems to be a wire (!) , is that supposed to be there? I attach some photos of different open ports. Plenty more questions, but for now these will do. Thank you all for your help/advice.

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Chip it out the rust scale. Can clean up the frost plug bores with a wire wheel to size on a drill, then some sand paper.

Have used a long 3/16" drill bit while vacuuming with a shop vac and a 3/8" steel tubing with the end slightly flattened so you can scrape with it too.

1/8" steel weld rod for poking in there and scraping by hand.

3/16" brake line length on an air blower with high pressure air... while vacuuming at the same time.

It will clean up, just have to keep at it.


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The rod is left over from making the block, it can stay or pull it out, your choice. Rinse that out with the garden hose. Lots of crud will come out,
 
The "wire" is left over from the casting process. Very common. Nothing to worry about. I'd knock the freeze plug back in. The I'd remove the thermostat. Put the thermostat housing back on (I'd ust RTV for now). Plug off the water pump inlet for the bottom hose. Next, get a gallon of CLR from the grocery store and dump it in the engine through the thermostat housing. Let it sit for a few days, then come back, remove your plug on the water pump inlet and flush the engine.
 
I'll add that I would NOT put CLR in the radiator. You need to isolate the radiator from the engine and use the CLR only on the engine. Depending on what the radiator looks like, you may need to take it to have it professionally cleaned. It's probably pretty rough. It would also not hurt to back flush the heater core.
 
Chip it out the rust scale. Can clean up the frost plug bores with a wire wheel to size on a drill, then some sand paper.

Have used a long 3/16" drill bit while vacuuming with a shop vac and a 3/8" steel tubing with the end slightly flattened so you can scrape with it too.

1/8" steel weld rod for poking in there and scraping by hand.

3/16" brake line length on an air blower with high pressure air... while vacuuming at the same time.

It will clean up, just have to keep at it.


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Thanks, air compressor comming soon... hope do not need to take out the cylinders like U did, thats a bit beyond me... :)
 
The "wire" is left over from the casting process. Very common. Nothing to worry about. I'd knock the freeze plug back in. The I'd remove the thermostat. Put the thermostat housing back on (I'd ust RTV for now). Plug off the water pump inlet for the bottom hose. Next, get a gallon of CLR from the grocery store and dump it in the engine through the thermostat housing. Let it sit for a few days, then come back, remove your plug on the water pump inlet and flush the engine.
That's what i do and have great results then i add a bottle of this to the rad .
WIX 24058 Radiator Liquid Cooling System Treatment, Antifreezes & Coolants - Amazon Canada this stuff is amazing , no more corrosion .
 
The "wire" is left over from the casting process. Very common. Nothing to worry about. I'd knock the freeze plug back in. The I'd remove the thermostat. Put the thermostat housing back on (I'd ust RTV for now). Plug off the water pump inlet for the bottom hose. Next, get a gallon of CLR from the grocery store and dump it in the engine through the thermostat housing. Let it sit for a few days, then come back, remove your plug on the water pump inlet and flush the engine.
Thanks! thermostat is gone as is the water pump, i'll wait till I get replacements... Impossible to get in Greece, way too expensive to get from US with the new taxes etc... probabbly I will just plug everything somehow and do it, its allready been through vinegar once....
 
I'll add that I would NOT put CLR in the radiator. You need to isolate the radiator from the engine and use the CLR only on the engine. Depending on what the radiator looks like, you may need to take it to have it professionally cleaned. It's probably pretty rough. It would also not hurt to back flush the heater core.
Radiator is out allready, lotsa dirt, good water flow, I think I will fill it up with vinegar for now and see... all brass I think by the way

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Don't fill the radiator with vinegar, my ruin it.

Forget the home remedies.

After you get all of the chunks of crud rinsed out of the system. Go buy Thermocure by CRC Cleans up crusty cooing systems really well. Wont have anymore rust stains in there.

Amazon and summit sell it.

Athens Greece, well that's a ways away! not sure if it's sold there, or if you,can ship liquid there. It is very good cleaner for cooling systems and will not harm brass or aluminum parts.

I had a race car with only water in it, cleaned it all up just like new, no more brown residue.
 
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Forget the home remedies. After you get all of the chunks of crud rinsed out of the system. Go buy Thermocure by CRC Cleans up crusty cooing systems really well. Wont have anymore rust stains in there.

Amazon and summit sell it,
Thanks, i've come across it, any idea how much I need for this engine? 225 3.7
 
One jug mixes with 3 gallons.
Service manual says a /6 takes:
13 quarts witha 19" rad
14 quarts with a 22" rad.

4 quarts per gallon So 12 quarts is 3 gallons.

you need two jugs of it. Instructions encourage you to drive the car and get it hot. Leave it in for days up to a week if necessary, and I would with your car.


This has no freeze protection so all the cold weather people be careful.
 

I've run "iron out" and water in a few, says it cleans cast iron home heater radiators so why not a cast iron car block.
Prestone used to sell the same stuff in a cardboard can a little smaller than a can of kitchen cleanser. Not "iron out" exactly but "oxyallic (sp?) acid which is what iron out exactly is. Flush as best as you can, fill with straight water, put about a cup of iron out in, and let it run til warm plus a while, flush again til as clear as possible, repeat if needed. I've been surprised at how much crap comes out... If need be pop a freeze plug and flush some more.
The worst one that I ever had to do was a 318 in a 73 van with an extendable crank up camper top
 
Those block pictures look as bad as my boat motor. I just flushed it out forwards and backwards, and from a few different orifices... It ran like a champ after that..
 
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