I have a 1965 mustang with a 74 302 motor it’s very rusty in the radiator (brand new less than 2 months old) already stopped up with rust what can I poor in it to sorta cut the rust to remove it I’ve took thermostat out and ran gallons of water in the top hose and let it run out I’ve tried 4-5 Preston’s flush kits 2 blue devil kits I’ve tried CLR and evaporust and they all came out rusty but still got more I’ve even filled block and radiator up 10-15 time ran it 10-15 to get warm and it still not come clean any help is appreciated
I think you’ve proved there’s a lot of rust inside the engine. You’ll just have to keep doing what you’ve been doing. Drain , refill, run engine, etc etc. Eventually all the rusty sediment will be gone and hopefully there’ll still be enough engine metal left to keep it running. You have a 65 Mustang in your possession, so things can’t be all bad 
You might want to eliminate the heater as a rust source by bypassing it for this exercise. I think Ray said on the show their shop uses a product containing oxalic acid for this purpose.
1 Like
You can remove the water pump and other hoses and fill the engine with Muratic acid…rinse and repeat till all the rust is gone. Its messy but it will do the trick.
3 Likes
Any chance you’re up for an engine rebuild? Sounds like that block has seen better days.
Installing a coolant filter in the heater hose might eventually clear up the coolant
http://www.wixfilters.com/Products.aspx?ct=phcf
and there are plenty of easily adaptable filter mounts available
I have a few of those adapters laying around from long ago when they cost less than $5.
1 Like
I’d probably try something like this first. Least amount of effort and if it works, great!
If you try that stuff please post your results @Tanerphillips10_149221. It does sound promising.
I think Rod’s spamming. Trying to sell his old lot of adapters.
I kid, I kid!
2 Likes
Carolyn wouldn’t like that @Scrapyard_John. And we don’t want to make Carolyn mad do we.
Sorry. False alarm!
Where is a good cheap place to buy some and is it safe for gaskets
I poured some into the car yesterday I’m gonna let it set for about 5-7 days starting it and drive it all I can and will keep you updated on how it is
Thank you I bought some and I will give it a try
I’m curious to know if said product has Muratic acid in its ingredient list.
I’d take the vehicle to someone who has a cooling system flush machine.
That’s the only way you’ll get all the rust out.
Tester
The label says DRAIN & FILL and I wouldn’t expect it to do more @Tester. Have you operated one?
The image is my coolant flush machine.
The problem is, you put the chemical in, run the vehicle and the corrosion contaminates the entire cooling system.
Then you shut the engine off, the water pump stops pumping, and the coolant stalls and all the contaminates settle out of the coolant in the radiator, engine block, heater core, hoses, etc…
You drain the radiator and all looks good.
You fill the system with new coolant, drive the vehicle, and all the settled contaminates still in the engine block, heater core, hoses. etc…, returns.
Tester
Back in the GOOD OLE DAYS when a cars cooling system became plugged the radiator was removed and rodded out and before reinstalling it the thermostat was removed and water with shop air to boost it was run from the top to back flush the engine. The results were outstanding. Of course these days imported aluminum radiators cost less than the cost of rodding and the entire cooling system maintenance situation has changed. And a significant reason for your machine is it enables a full service shop to offer a reasonably good job of cleaning the cooling system without flooding the floor.
But as for the OP, I can’t imagine how repeated back flushing with a garden hose didn’t significantly improve the situation. And like all snake oils I always watch and wait for others to prove how effective and safe they are before I stick my neck out.
If the cooling system is dumped and given a DIY Prestone heater hose back flush every 3 years, and barring some other problem like a transmission cooler failure, I can’t imagine ever having a problem with rust or the usual scale that accumulates in the hot side tank on a radiator and the lower flues.
You might want to read the about the product more carefully. It works through a process called chelation. The bonded metals are held in suspension. Chelation is a well known and understood chemical process also used in medicine to remove toxins from the body.
I ran some through for about a week and drained it It seemed to do the trick very recommended if there’s tons of rust. Light rust I’d use cheaper