Back flushing the radiator

By disconnecting the top and bottom hoses and applying water pressure to the bottom radiator hose neck. The catch is you are fighting gravity, a baffle, etc. You can do the block at the same time though.
 
you can, but to do it right you need a back flush tool, like the ones radiator shop use, its cone shaped so it can be wedged in the bottom radiator outlet, water and air hooked to it, the air creates turbulence to loosen crud, and the water to flow it out, check at your local parts store to see what it looks like, they may even have one to loan
 
As mentioned, you can somewhat do it, but I'd remove the radiator and turn it upside down to see if any rust flakes come out.

Have you tried Cascade to remove any grease, and 30 days of vinegar to remove rust and hard water deposits?
 
Tom Wesenberg said:
As mentioned, you can somewhat do it, but I'd remove the radiator and turn it upside down to see if any rust flakes come out.

Have you tried Cascade to remove any grease, and 30 days of vinegar to remove rust and hard water deposits?
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Hi Tom. I just put the vinegar in two days ago, after my question to you about it. As you suggested, I'll leave it in about 30 days and then drain it.
 
Ray, be sure to drive it several times during the 30 days, so it gets heated and circulated. Had mine not worked after 30 days, I would have tried an additional 30 days. After that I would have unsoldered the bottom tank and rodded it out.
Sure glad it worked out after 30 days of vinegar and removing the radiator to flush it upside down, as I didn't want to disturb an original radiator unless absolutely neccessary..
 
I built the two (2) PVC adapters shown in "The Restorer", September/October, 2012; pages 9 and 10.

One back-flushes the block, the other the radiator.

I took the magazine to my plumbing supply store and let a master plumber pull the necessary parts. He thought it was a great use of PVC Schedule 40.

After completing a month of Tom's Vinegar Spa treatment, I back flushed everything and watched the brown water flow!

My underdash Rexaco is showing a decidedly cooler system, even in the muggy and hot conditions in the South for the month of June!

I'd highly recommend building a pair of backflushers for the times when you don't want to demount the radiator.
 
roccaas said:
I built the two (2) PVC adapters shown in "The Restorer", September/October, 2012; pages 9 and 10.

One back-flushes the block, the other the radiator.

I took the magazine to my plumbing supply store and let a master plumber pull the necessary parts. He thought it was a great use of PVC Schedule 40.

After completing a month of Tom's Vinegar Spa treatment, I back flushed everything and watched the brown water flow!

My underdash Rexaco is showing a decidedly cooler system, even in the muggy and hot conditions in the South for the month of June!

I'd highly recommend building a pair of backflushers for the times when you don't want to demount the radiator.
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Thanks! Somehow I had missed that article. I'll get the parts tomorrow!
 
Tip: when back flushing the radiator, hook up the block flusher to the water pump side of the upper radiator hose. This way you can direct the gradoo from the radiator down under the frame rather than splashing all over the engine etc.
 
It's a Southern thing for any icky stuff nobody wants on their clothes or driveway. In Louisiana I believe it is Gra-deaux.
 
I wondered if it was a Jawja term; I hear those occasionally from my wife's family (Meansville, Barnesville, Marietta), but I hadn't heard that one. :)
 
700rpm said:
I wondered if it was a Jawja term; I hear those occasionally from my wife's family (Meansville, Barnesville, Marietta), but I hadn't heard that one. :)
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Do they ever bring up; "rise up outta the grave and ****** 'ya bald headed", or "that's some slap 'yo Momma (sweet tea, fried chicken, peach pie, corn likker, etc)

We're all "dumb like a fox" down here, so watch out!
 
roccaas said:
Do they ever bring up; "rise up outta the grave and ****** 'ya bald headed", or "that's some slap 'yo Momma (sweet tea, fried chicken, peach pie, corn likker, etc)

We're all "dumb like a fox" down here, so watch out!
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Yeah, sometimes I feel like I'm in another country when I'm there.. I love to drive the back roads and small towns in GA. Beautiful state.
 
The darn Vinegar treatment sure works well to loosen all the junk in the system so that it can be caught by the filter (The small tubes in the radiator). Ask me how I know. Doing the vinegar treatment without installing an in-line coolant filter (like a gano) in the top hose is a total recipe for disaster, that will result in having to rod out or replace the radiator and no amount of backflushing will solve it typically.
 
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I put a gano filter inline in my top radiator hose after I installed my rodded-out radiator, and blasted out my block. It is well mad brass construction but the mesh screens are to open so I added a piece of nylon hose and I am catching a teaspoon of fine sand like material and larger chunks every 20 miles or so.


http://www.ganofilters.com/

I plan on posting pictures soon
 
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Out of curiosity, why place the filter on the top hose (where grit will fall back into the motor and gravity will work against the filter) as opposed to on the bottom hose (to keep grit from entering the motor and where gravity will keep sediment in the metal tube?
 
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