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Main Forum => General Discussion => Topic started by: Mouse on Mar 07, 2024, 04:05 PM

Title: Radiator and engine block flush out and coolent replacement
Post by: Mouse on Mar 07, 2024, 04:05 PM
Hi another Newbie question again from me. Ive noticed my radiator water looks incredibly brown. I have the Wittsend service data sheet (very useful thanks) but could anyone advise on the steps to drain engine and radiator. Ive ordered blue coolant and plan to mix at a 33% ratio with deionised water.
It has a heater added in the cab. Locations of valves would be useful as on a quick inspection I couldn't see one on the radiator.
Grateful for any help.
Title: Re: Radiator and engine block flush out and coolent replacement
Post by: diffwhine on Mar 07, 2024, 04:15 PM
You should have a drain bung on the bottom edge of the radiator. Most Series radiators have them. If not, you have to pull the bottom hose. You also have a drain tap in the left hand side of the block in the dipstick and exhaust area. Might be worth removing the hoses and gently putting a garden hose through and flushing the whole system through once drained. The drain tap on the block often bungs up, so expect to have to remove it and refit it after cleaning it and the drain hole it screws into.

Used antifreeze is a hazardous substance, so should not be allowed near any watercourse, drain or pet. Cats in particular seem to like the sweetness of antifreeze with disastrous consequences.
Title: Re: Radiator and engine block flush out and coolent replacement
Post by: Talullah on Mar 07, 2024, 04:21 PM
I used this stuff once I had cleaned the whole system the way that Diffwhine explained.
Title: Re: Radiator and engine block flush out and coolent replacement
Post by: Wittsend on Mar 07, 2024, 05:08 PM
Before draining down it would be worth running the engine with some de-scaler added to the rad water.
Instructions on the bottle.

Other have had good results by putting a couple of dishwasher tabs in the rad and running the engine round for a couple of days.

Then drain, and back flush through the block and rad with a hose pipe. You should be good to go then.


 :RHD
Title: Re: Radiator and engine block flush out and coolent replacement
Post by: StuartC2 on Mar 07, 2024, 06:52 PM
check out AutoRestorer.com
Interesting articles and one on vintage vehicle coolant
Title: Re: Radiator and engine block flush out and coolent replacement
Post by: island dormy on Mar 07, 2024, 08:27 PM
   You should also back flush the heater core (to get better heat out of the heater) by removing both of the hoses and running water through "At Low Pressure" do not use high pressure to back flush the heater core it will burst. Do it both ways you will be amazed at the amount of sediment that comes out.
  Depending on how long the heater core hoses have been on you may have to run a small screwdriver up and under where the hose goes onto the pipe to get the hose off. Or maybe even cut the end off the hose.

   Victor
Title: Re: Radiator and engine block flush out and coolent replacement
Post by: StuartC2 on Mar 08, 2024, 12:45 AM
have attached the coolant article from Autorestorer.com rather than being bombarded with popup ads on their site.
Title: Re: Radiator and engine block flush out and coolent replacement
Post by: NoBeardNoTopKnot on Mar 08, 2024, 08:05 AM
One of the oddities of chemistry is that it doesn't play fair.

You'd think 100% coolant/anti-freeze would be best? Nope. 100% coolant fails to give you a lower freeze-point. You need a mix. Usually 30-50%. Other fluids are the same...

The boy-racers insist on brake-fluid upgrades to say DOT5.1. Nope, this will usually  fail. DOT5.1 from DOT 4 won't be an upgrade. If there's DOT 3/4 brake-fluid already in there, likely it'll lower your boil-point to under both. It won't matter how mahoosive your boom-box is in the rear, you'd need to be entirely rid the DOT3/4 before you'd see a 'true' go-faster upgrade. To keep it simpleton, the container will say you can mix glycols, and you can but... keep chemistry in mind.

You won't need DOT 5.1 in a Series anyway, it won't last like  DOT3/4. either. but you get the idea. Chemistry doesn't do what you'd think.

In an ideal world you don't mix tap-water. You buy distilled or de-ionised. Lower pH. Of course, there's that water-less stuff.
Title: Re: Radiator and engine block flush out and coolent replacement
Post by: Mouse on Mar 20, 2024, 07:46 AM
Thank you for all your helpful advice.
m