Sludge in radiator - Best way to remove it

BG_

Hi,

Noticed that my engine coolant was turning brown in my 03 Fiesta 1.4, so I thought I really should change it.

Got under the car, unscrewed the drain plug and only a few sludgey drips come out. Which is never a good sign. Looks like it's never been replaced the life of the car and previous owner(s) must of been putting any coolant in.

Is there anyway I can get this sludge out myself, or will the whole radiator need replacing?

thanks

straighttalker

I'd replace it myself. You never know how much sludge is in there and I doubt you'd be able to get all the channels cleared with just a flush. Had a look on EuroCarParts. A cheap radiator is around £40-£45 dependant if for a diesel or petrol car. Double that price for a decent branded Hella one.

Foxy-Stoat_3

Maybe some bright spark has used K-Seal at some point in its life, or its rusty carp from the system.

There are coolant flush products on the market, only issue maybe is that you move the radiator sludge into other areas of the coolant system, heater matrix or thermostat etc.

As said, replace the radiator if cheap enough and maybe flush the heater matrix using a hose pipe, if the two hoses that go through the bulkhead are easy to get to.

AdrianC

Another vote for a full cooling-system going-over.

But a thermostat and a rad. Rad off, 'stat out. Hosepipe in the 'stat housing and flush the block through. Repeat in reverse through the bottom hose - you might need to do something mildly ingenous to help the water stay in there. Replace any hoses that look ropey.

Put it together, fill it with plain water, run it until the fan cuts in. Drain it. If it still looks manky, repeat. DO NOT leave it overnight, full of plain water, at this time of year. Then, when you're done, fill with proper coolant mix.

angrycrow

This does sound like someone has used a product to try and seal a leak somewhere. In view of this may be worth a compression test to make sure the headgasket is not on the way out. Compression tester is only £20 and the full test can be done in under an hour.

To clean out the rad I normally take it out and flush it both ways in the bath using hot and cold water from my shower. (Shower head removed allows the shower pipe to be shoved into the rad). I do have very high water pressure so this chucks out all the muck and it is surprising how much slugde can come out of a rad. As said earlier whilst its apart change the thermostat and back flush the block.

JustinR1979

Or maybe a less dramatic leak...!
Just fix the known issue first

Strider590

I don't know what people have against the radiator leak repair stuff, when used for the correct thing (ie not a HG failure), there's nothing wrong with it.

It's just small lumps of rubber like material, which when it finds a small gap (less than 1mm) simply forms a blockage.
It gets blamed for all sorts of other problems, but from what i've seem those were cases where HG failure had occurred, causing emulsified oil to build up in the cooling system.

I had a leak in my radiator seem 3 years ago, I used rad weld I had no more leak until this year when the cambelt and water pump was replaced. I stood and watched the coolant come out of the engine, it was also flushed through, there was no gunk or other horrible stuff.

The real problems come in when people use the recommended quantity per litre of coolant, find it didn't work and then start shoving bottle after bottle of the stuff in there.



As for OP, remove the bottom radiator hose and with the engine cool, run warm water into it via the expansion tank (use a hose and an old towel to form a seal). Then remove the radiator top hose and do the same with the hose directly into the radiator.

You will probably need to purchase some 34mm hose clips (but check the size first), DO NOT BUY CHEAP, use good quality GENUINE Jubilee or JCS Hi-Torque hose clips only.

NOTE - You won't be able to flush the radiator without removing the top hose, because the thermostat will be closed.

AdrianC

Strider590 wrote: »

I don't know what people have against the radiator leak repair stuff, when used for the correct thing (ie not a HG failure), there's nothing wrong with it

It's horrible bodgegoop, which only has a place in a car that you're trying to squeeze an extra year out of on a shoestring.

If you use it long-term, then - yes - you may well find it seals just fine. Until the next time the coolant's changed, at which point you'll re-find that leak, along with other minor leaks that the bodgegoop has masked. If you're really lucky, the original fault that lead to a minor leak won't have spread, so you won't find out by all the hot, pressurised coolant turning what could have been fixed when it was a minor leak into a sudden emptying of the cooling system.

facade

In The Olden Days, when cars were made properly, from decent thick metal, we used to use flushing agents that were basically hydrochloric acid.

These were put in and the engine run for a while to heat it all up. Any rust or scale would become a soluble chloride salt, that washes out, then we put a mild alkali in to kill the acid residue, washed out and refilled.

However, on most cars, it was the rust & scale that kept the pinhole leaks in the heater core & radiator sealed, so we then had to put in Barrs Leak (as recommended by Jaguar, and anybody who used gravity cast engine blocks that were porous to start with)

I'd keep filling up the radiator to the top, and pulling the bottom hose off, then replace & refill until it runs clear.

You can try removing a hose and attaching the hosepipe to one end and forcing water out of where it was removed, but the low flow rate tends to only clean a small path.

londonTiger

facade wrote: »

In The Olden Days, when cars were made properly, from decent thick metal, we used to use flushing agents that were basically hydrochloric acid.

These were put in and the engine run for a while to heat it all up. Any rust or scale would become a soluble chloride salt, that washes out, then we put a mild alkali in to kill the acid residue, washed out and refilled.

However, on most cars, it was the rust & scale that kept the pinhole leaks in the heater core & radiator sealed, so we then had to put in Barrs Leak (as recommended by Jaguar, and anybody who used gravity cast engine blocks that were porous to start with)

I'd keep filling up the radiator to the top, and pulling the bottom hose off, then replace & refill until it runs clear.

You can try removing a hose and attaching the hosepipe to one end and forcing water out of where it was removed, but the low flow rate tends to only clean a small path.

thicker metal isn't always better, Old cars are notorious for rusting because they used low quality steel that would rust. They made up for the low quality by just making it thicker. In the case of radiators you want the blades to be as thin as possible so the heat can transfer to the surface easier to be wicked off by air. If the blades are too thick they will have an insulating effect.

Cars use less steel, yes. But they have higher quality steel and are more structurally sound.

BG_

Thanks for all replies guys.

The problem is that i'm not mechanically gifted enough to take the rad out. Changing the coolant 'was' going to be the most advanced job I was going to do to my car lol.

I think this may be the deciding factor that I may get rid of it anyway due to me going traveling for 4 months, so I wouldn't be using it anyway. Seems like in the long run it could cost a small fortune. If there is something in the radiator that fixed a leak.

Hmmmm.... Decisions.