Anyone have any good ways to clean out a partially plugged radiator without removing it from the car? My 49' is overheating on the highway suddenly. It was fine for a week, and then suddenly on the way to Mokan it started overheating. Its running a little rich, timing is set to 36 degree total on the 262ci v6, and its using a V8 rad from a 74' Dodge dart, and an electric fan. I thought the thermostat went bad, so I removed the guts from it and its just acting as a restrictor. There are no leaks. The water looks like rusty mud now, and I think its all from the block. I have flushed out the block with a garden hose now, but I think the crap has partially plugged the raditor. I am thinking or trying a gallon of white vinegar in the cooling system for 15 minutes then draining. Anyone have any other solutions?
My local radiator shop hot tanked mine in about an Hour. I know thats not what you asked, but I figured I let you know. I thought they would have it for several days(it had a small leak also). And I did'nt want my car of the road that long since I drive it daily. But I was wrong. They had it back to me in a couple hours. and it was like $40.00. Call around...You might be supprised?
I've heard reverse flushing it gets a lot of crud out, but I don't really know jack about it. Someone enlighten us, I'm also gonna flush my rad/block this week when I replace a leaking water pump...
If you can block of the lower spouts, fill it with CLR and let it sit for a few days (probably should leave the cap off) That should take care of any rust, calcium scale, etc... If you can believe the commercials Flatman
I made an,"on the road" radiator repair once but the radiator had already been pulled.You might be able to do this in the car but I would take it out. Where I was(upstate New York)wouldn't flush out the radiator due to EPA regs so I bought a gallon of Liquid Plum-r at the local hardware store,poured it in after sealing the openings and filled it nearly full with water.Let it set for about 3 hours(rotating it 90 degrees every 20 minutes),reverse flushed it with a garden hose several times and re-installed it in the car.Worked for almost a year before it started overheating again.This time I had it re-cored. When you're 300 miles from home,you improvise.
I've had them flushed at radiator shops with good results. A couple of the suggestions here sound good also.
Your hardware store has 1 gal. concrete cleaner containing diluted muriatic acid. You can use it straight from the container and leave it in the radiator over night. You will not believe the amount of sediment and scale build-up it removes on clogged radiators. Pure muriatic acid would attack the soft metals, so be careful. If done right, it leaves the treated metal shiney like new. Vinegar or citric acids are OK, but they are not very strong acids, taking forever to work. Unless you get highly concentrated pure citric acid. LCR is just too expensive compared to concrete cleaner.