Series 2 Flushing and changing coolant

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Hi All,

My series has only got water in it at present. So went out and bought some coolant a little while back.
Just want to confirm the process step by step.

Remove drain plug from rad

Remove plug from engine block

let drain

put both plugs back in

fill with water

run for a few mins

let it cool

drain rad again (but not block?)

fill with coolant/water mix

anything I’m missing?

cheers
Depends on how bad you think it is. On an old thing, if I think there is a lot of rust and sludge in the system, I drain as much coolant as possible, pull off both radiator hoses, and stick a garden hose wrapped in tape into the bottom outlet of the radiator, and leave it until it runs clear. This can be overnight in some cases.

Then I refill with the antifreeze mix, and run it around for a bit. After a while, sludge and rust from the engine block have usually transferred into the rad, so I repeat the process until I think it is OK, or I have had enough.

Be aware that if you add antifreeze to a system that has been running water, it has a habit of finding leaks that were not there previously.
 
Thank you! Only container I have to mix in us a 1.5 litre cleaned Pepsi bottle. So I’ll be doing a fair few loads I reckon

was going to do 33% coolant. Rest water.
Just looking at a vintage Series 2 and 2a manual, which happens to be on the table in front of me.

The capacity of the 2 Litre petrol engine coolant system is stated to be 17 Imperial Pints, (9.5 litres for Europhiles).

So 2 litres of antifreeze isn't going to get you to the 25%, let alone 33%.
 
Just looking at a vintage Series 2 and 2a manual, which happens to be on the table in front of me.

The capacity of the 2 Litre petrol engine coolant system is stated to be 17 Imperial Pints, (9.5 litres for Europhiles).

So 2 litres of antifreeze isn't going to get you to the 25%, let alone 33%.
understood, thank you again.

Back to halfrauds.
 
If I remember correctly, that drain tap turns to open the opposite way to what you would think.

I believe you have to turn it clockwise, which would at first seem that you were tightening it. Don't force it too much, it can always be completely removed with a spanner if needed.
 
I wouldn't touch the taps on either the rad or engine block, they have a habit of snapping off. I'd under the top and bottom hoses, consider replacing them if they are old, flush out with a hose as suggested, replace the hoses and pour 5 litres of antifreeze in and top up with water. Run the engine for a few minutes and then top up with antifreeze if necessary. For about £1 you can buy a 5 litre container of water from Sainsburies. They are useful for mixing antifreeze and Demi johns. 50% mix is what I aim for but if it's stronger, it's not a problem. Antifreeze reduces the boiling point of the coolant as well as preventing it from freezing.

Col
 
I find mixing anti freeze in a watering can makes it easy to pour into Radiator , any excess mix I then store in the empty anti freeze bottles marked as mixed.
 
I wouldn't touch the taps on either the rad or engine block, they have a habit of snapping off. I'd under the top and bottom hoses, consider replacing them if they are old, flush out with a hose as suggested, replace the hoses and pour 5 litres of antifreeze in and top up with water. Run the engine for a few minutes and then top up with antifreeze if necessary. For about £1 you can buy a 5 litre container of water from Sainsburies. They are useful for mixing antifreeze and Demi johns. 50% mix is what I aim for but if it's stronger, it's not a problem. Antifreeze reduces the boiling point of the coolant as well as preventing it from freezing.

Col
That is what I do. Hoses off, you don't usually get a problem with hose clips, and if you do, you just replace them.

On some engines, you can get the spout of a fluid extractor all the way down the radiator, so you don't even need to remove the hoses, unless you want to flush.

I rarely pre mix either, just pour in a bit of water, then a bit of antifreeze, then a bit more water, and start up.
 
Depends on how bad you think it is. On an old thing, if I think there is a lot of rust and sludge in the system, I drain as much coolant as possible, pull off both radiator hoses, and stick a garden hose wrapped in tape into the bottom outlet of the radiator, and leave it until it runs clear. This can be overnight in some cases.

Then I refill with the antifreeze mix, and run it around for a bit. After a while, sludge and rust from the engine block have usually transferred into the rad, so I repeat the process until I think it is OK, or I have had enough.

Be aware that if you add antifreeze to a system that has been running water, it has a habit of finding leaks that were not there previously.

Maybe that's because you moved all of that sludge out of the way ? ;):D
 
50% mix is what I aim for but if it's stronger, it's not a problem.

I had read before not to go over 50% mixture as the antifreeze apparently does not absorb heat as well as water.

I have one of the Sealey antifreeze testers that looks like a meat baster. Five of six floating discs is the maximum recommended concentration, all six discs floating is marked as "not safe", so that seems to suggest that too high concentration is also not wanted.
 
I had read before not to go over 50% mixture as the antifreeze apparently does not absorb heat as well as water.

I have one of the Sealey antifreeze testers that looks like a meat baster. Five of six floating discs is the maximum recommended concentration, all six discs floating is marked as "not safe", so that seems to suggest that too high concentration is also not wanted.
I wouldn't go that strong on an old engine. Not a problem on new stuff.
 
Just to repeat the advice - do not touch that drain tap! There are so many ways that can end badly. If its only had water in you may find a lot of corrosion under the rad hoses. The anti frezze will search them out so be prepared to take the hoses off, clean up the metal and re-seal.
 
For how cheap the coolant hoses are, once you have gone to the trouble of taking them off, you may as well replace them.

Old ones harden with age, and often do not reseal properly when refitted.
 
For how cheap the coolant hoses are, once you have gone to the trouble of taking them off, you may as well replace them.

Old ones harden with age, and often do not reseal properly when refitted.

It'll give you a chance to clean the gunge off of the fittings so they seal well first time ...
 
I have read that some types of grease can react with the hose rubber and cause it to break down quicker. Again I cannot say if that is really true.

Wetting the inside of the hose end with plain water before fitting it can also help them push on easier.
 
Just to repeat the advice - do not touch that drain tap! There are so many ways that can end badly. If its only had water in you may find a lot of corrosion under the rad hoses. The anti frezze will search them out so be prepared to take the hoses off, clean up the metal and re-seal.
i gave it a good attempt at a turn yesterday when i was doing this, however it didn't even budge and cut into my hand a bit. So i have and will continue to leave it.
 
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