Defender 90 300 Tdi - Coolant Recommendation Thread

[ryan_1993]

Hi all,

Seen a few postings regarding coolant on here, but many of them are over 10 or 12 years old now. Not sure if things have moved on in that time or not?

I am going to be flushing my radiator and cooling system in coming weeks and replacing my anti-freeze. I am not entirely sure what I need to go for though. Some folks say to avoid the pink stuff as that's no good with an aluminium head, and stuff what mentions OAT can cause issues with rubber hoses??

At the moment I was thinking of buying this from Halfords, as the description says ethylene glycol, which is what a few have said the 300 Tdi likes?

Comma G48 Antifreeze and Coolant RM 5L | Halfords UK

I really am open to any brand I just want something what is decent and what won't lead to issues as I'll be doing a 1000 mile trip to Scotland in April, followed by a trip to Holland in May. I'll also be buying some distilled water as well. I am not sure how long ago coolant was last done, so its probably well overdue.



Any other suggestions?

P.S If it makes any difference mines a T-reg 300 tdi so quite late

 

[tottot]

What's in it now? Green or blue stuff I suspect, It would have been the type used by most vehicles of that time.

 

[ryan_1993]

What's in it now? Green or blue stuff I suspect, It would have been the type used by most vehicles of that time.

hard to say as I replaced some hoses last year and lost some, but not all coolant and just added some of the universal stuff from Prestone, which I probably shouldn't have done, but it was only a small 1 litre bottle for a top up.

I can't really remember but this time I am going to totally hose and flush out the entire system and also put in distilled water as well.

 

[tottot]

For TDI's use Ethylene glycol based 50 50 water mix [or ready use] Td5's have the OAT stuff.
11 Lts and a tad for a full refill but heater unit can not be drained. Remove a pipe and flush with hose
It is important with a 300 to do a good bleed of air from system. Good to park facing up hill some and fill from the plug on the rad. Run with plug our until heater gives some warmth and no more bubbles at the rad plug.

 

[lynall]

Bottom hose off drain it all out, refit hose, chuck in 5 litres of blue glycol then top up with plain water, follow bleed procedure before starting.
Buy concentrate not ready mixed as why pay for water?

 

[ryan_1993]

Bottom hose off drain it all out, refit hose, chuck in 5 litres of blue glycol then top up with plain water, follow bleed procedure before starting.
Buy concentrate not ready mixed as why pay for water?

Thanks, this is what I bought in the end Comma SCA5L 5L Super Coldmaster Antifreeze and Coolant Concentrate , Blue : Amazon.co.uk: Automotive

That seems like it will work

 

[GRATCH]

Blue or green is good. 300tdi and earlier need IAT, not OAT coolant.

 

[lynall]

Blue or green is good. 300tdi and earlier need IAT, not OAT coolant.

There is another new one out I read about the other day NOAT it was.

https://www.cumminsfiltration.com/NOAT

 

[ryan_1993]

Is using Distilled water okay? Or should I just use tap water?

 

[Turboman]

Is using Distilled water okay? Or should I just use tap water?

Distilled is fine if you don't mind spending the money.

 

[ryan_1993]

Distilled is fine if you don't mind spending the money.

thanks yeah already ordered. Is it worth adding something like a radiator flush maybe a week before changing the coolant so it can be breaking down all the crap how long can you keep it in before you need go change coolant?

https://www.halfords.com/motoring/engine-oils-and-fluids/engine-cleaner-and-degreaser/wynns-radiator-flush-211134.html

 

[Turboman]

thanks yeah already ordered. Is it worth adding something like a radiator flush maybe a week before changing the coolant so it can be breaking down all the crap how long can you keep it in before you need go change coolant?
https://www.halfords.com/motoring/e...nd-degreaser/wynns-radiator-flush-211134.html
https://www.halfords.com/motoring/e...nd-degreaser/wynns-radiator-flush-211134.html

I have never used radiator flush in 40 years of working on vehicles and machinery.

 

[tottot]

As above, never used the stuff. When have had a somewhat gunky system have just opened drains / loosened hoses and then stuck a water hose in and let it run until water clear.
.

 

[GRATCH]

I would drain the coolant and flush with clean water.
Fill up with water and add the flush, then go for a 30 min drive.
Then drain and flush with clean water.
Fill up with water and go for a 30 minute drive.
Then drain and flush with clean water.
Then fill up with coolant, go for a 30 minute drive, then top up coolant.

 

[lynall]

thanks yeah already ordered. Is it worth adding something like a radiator flush maybe a week before changing the coolant so it can be breaking down all the crap how long can you keep it in before you need go change coolant?
https://www.halfords.com/motoring/e...nd-degreaser/wynns-radiator-flush-211134.html
https://www.halfords.com/motoring/e...nd-degreaser/wynns-radiator-flush-211134.html

You are over thinking it, drain down refill bleed done