Coolant change - ethylene glycol versus safer propylene glycol?

[Malc_Bateman]

My first job of the winter is to change the coolant hoses to the silicone variety. I'm a relative novice and I've been advised to flush the system with "Classic Coolant Cleaner" and then use "Classic Coolant Pre-Mix". Question (1) : do I flush before I change the hoses or after? Question (2) : Any views welcome on the merits of toxic ethylene glycol versus safer propylene glycol?

Background - my "7" is 14 years old, only 18 months in my ownership. 13,500 miles from new - Vx 8 valve with Kent Cam (if that makes a difference!). No leaks, no temp probs, runs sweet - just hoses perished.

[Jonathan Kay]

Lots in the archives on this, including:

1

2

3

4

 

(Last week we taught our medical students about the toxicity of ethylene glycol and methanol.)

 

Jonathan

 

 

 

 

[SLR No.77]

Drain coolant

Change hoses

Refill with coolant (Bluecol)

 

Stu.

[NoLimits]

I have been using Evans Coolants PowerCool 180 this year and I have to say it has done what it says on the tin.

 

I had no pressurisation even when the engine reached 125 deg after someone forgot to turn the fan on. I took the cap off whilst it was still at 95 deg and not a sound.

 

No corrosion and for the life of the engine. It works out cheaper in the long run also.

[EFA]

If your name is Bob and you like Landrovers and helicopters, then ethylene glycol is to be recomended. Make sure your car has a slight leak.

[gundersen]

I tried to read up on this when I changed the coolant on my k-series seven, but only got more confused.

To sum up my findings:

1) Everyone have an opinion

2) No one have anything remotely scientific to back it up

 

So, good luck in your quest. As Jonathan writes, it has been discussed loads of times on the forum

[Malc_Bateman]

Thanks to one and all for your replies. I've now read through the topics highlighted by Jonathan (thanks for the links) and formed an opinion. Saturday will see the new hoses and coolant installed, then a quick blat to test for leaks et al on Sunday.

[prangerman]

If not already covered in the links posted by Jonathan, do regularly tighten up the hoses as silicon hoses seem to loosen more freely than the OE rubber hoses.

 

Peter

[Jonathan Kay]

I think you'll be fine with any of several coolant options, which is why this has never been resolved.

 

Good advice on retightening. I don't understand why people have such different experiences of this. I used silicone spray on the clips on my silicone hoses (from Classic Silicon Hoses) and none of them have needed retightening.

 

We've had a recent discussion about carbon monoxide. Here's the seasonal reminder to be careful with ethylene glycol and methanol. And especially careful about where you store it and what you store it in.

 

Jonathan

 

Edited by - Jonathan Kay on 14 Nov 2012 15:45:11

[GoogleTwit]

Govt advice on Ethylene Glycol here

[John Vine]

Quoting gundersen: 

No one have anything remotely scientific to back it up

There's quite a scientific discussion here. The main conclusions appear to be that (a) PG is a lot safer than EG, and (b) the secret of a good PG-based coolant lies in the additives.

 

JV

[gundersen]

Having read all four pages of that post, I still stand by my initial claim It does not contain a single decent scientific fact to back up any of the claims made.

 

However, it is just me being pedantic (I hear it is in fashion right now on blatchat 😬 ), we are running cars for fun not building rockets. So hearsay and anecdotal evidence is alight. There is rarely smoke without a fire, it is just when it comes to engine oils and coolant there are SOO many many people blowing smoke in different directions that it is hard to see the actual fire