any tips for upcoming coolant change

shaunthesheep · Post by **shaunthesheep** » 27 Oct 2002, 01:11

hi has anyone got any tips for my upcoming coolant change?, i heard about using bottled water?, but what type.
dom
Edited by - shaunthesheep on 27 Oct 2002 09:01:35

JohnD · Post by **JohnD** » 27 Oct 2002, 14:13

Hi Dom - Drain plugs on the rad and engine block. Before re-filling, two bleed screw should be opened, and the heater control to 'on'. I prefer to use a header tank made from a plastic bottle secured into the expansion tank and pour in a mix of 50/50 antifreeze and water. The water I use is collected from the dehumidifier. Fill until coolant runs from the bleed screws. Close the screws and start the engine without fitting the filler cap, and let it tick over for a few minutes. Switch off, fit the filler cap and run the engine until the fan cuts in. Allow to cool down and top up the tank if required.

shaunthesheep · Post by **shaunthesheep** » 28 Oct 2002, 04:03

where is the drain plug on the engine block?, i can only find the on the rad.
dom

JohnD · Post by **JohnD** » 31 Oct 2002, 23:30

Hi Dom - The plug on the block is on the back. Probably if you run a hose pipe through the expansion tank for a while as you drain the rad, you could get away with not touching the block drain plug.

shaunthesheep · Post by **shaunthesheep** » 10 Nov 2002, 03:19

john,
have brought 10ltr de-ironized water, rad flash & just in case some rad weld should a leak raise it ugly head.
will be poping into main dealer next week to buy antigel, then will add rad flush & go for a drive for about 20miles to get it going round the system.
dom

JohnD · Post by **JohnD** » 10 Nov 2002, 14:19

Cheers Dom! If I were you, I wouldn't use the radweld unless absolutely necessary.

shaunthesheep · Post by **shaunthesheep** » 10 Nov 2002, 15:33

cheers john,
what wrong with rad weld?, is there something i should know as i never had to used it before?
dom

alan s · Post by **alan s** » 10 Nov 2002, 15:40

Dom,
Check this info out that I posted on common faults; may be of some interest & help.
Alan S
http://www.andyspares.org/discussionfor ... IC_ID=1672

JohnD · Post by **JohnD** » 11 Nov 2002, 23:34

Hi Dom - I suppose there's nothing wrong with treatments such as Radweld, providing you recognise that they are only a temporary measure. I've never had much success with them and eventually ended up replacing a radiator. Also I'm not keen on the idea of putting something in the cooling system which is designed to solidify in the presence of air.

shaunthesheep · Post by **shaunthesheep** » 12 Nov 2002, 02:14

john,
so going on what every one's written, DON'T USE RADWELD if you can help it as it won't last very long.
will try not to use it.
dom

alan s · Post by **alan s** » 12 Nov 2002, 03:58

<BLOCKQUOTE id=quote><font size=1 face="Verdana, Arial, Helvetica" id=quote>quote:<hr height=1 noshade id=quote>
Hi Dom - I suppose there's nothing wrong with treatments such as Radweld, providing you recognise that they are only a temporary measure. I've never had much success with them and eventually ended up replacing a radiator. Also I'm not keen on the idea of putting something in the cooling system which is designed to solidify in the presence of air.

<hr height=1 noshade id=quote></BLOCKQUOTE id=quote></font id=quote><font face="Verdana, Arial, Helvetica" size=2 id=quote>
Dom,
Just adding to John's quote. One of my other vehicles is a Ford/Mazda which has been an absolute pain with cooling amongst a myriad of other problems. At one stage it sprung a leak in the radiator directly in front of the fan blade & as a result it naturally sprayed water vapour on to the exhaust manifold which did look spectacular; I thought so because I thought (was hoping anyway) that it was on fire. I used a "Radweld" type of additive & was quite impressed that the leak stopped almost immediately. As I never use the vehicle for anything but around town running, I noticed it started to get pretty hot by comparison to how it used to be but as it also had just been fitted with (another) new water pump, I put that down to possibly being that. My son has started using it as an emergency vehicle as his BX is presently undergoing a rebuild and now finds that after 25 klms it boils like a steam kettle and has pumped all the water out. Eventually we had to go over it to find the problem & sure enough; our sealant had worked so well that about 75% of the core of the radiator was blocked with the sealant. It's going to be a very expensive "cheap" fix. Never again!!
Alan S

NiSk · Post by **NiSk** » 12 Nov 2002, 13:16

Just a word of caution - if you use de-ionized or distilled water in your radiator, make sure you mix it with a good inhibitor or antifreeze containing an inhibitor!
De-ionized and distilled water are nature's most powerful solvents! It will turn an aluminium head on an iron block into cheese cake before you can blink!
NEVER top up with unmixed de-ionized/distilled water.
//NiSk

alan s · Post by **alan s** » 12 Nov 2002, 14:12

NiSk,
Could you please expand on the previous posting.
You're way over my head on a lot of this kind of thing and given my situation & location, I appreciate any advice you can offer in this regard.
I'm about to refill my system (on a BX 16V) with 95% ethylene glycol coolant. Given that I will be adding rain water from a concrete tank (hence alkyline) what percentage of ethylene glycol at the concentration I jave quoted would you recommend?
Alan S

NiSk · Post by **NiSk** » 12 Nov 2002, 18:47

Hi Alan,
Didn't mean to scare you!
I would always recommend using an antifreeze that has corrosion inhibitors. I'm pretty sure that most car manufacturers fill their cars with antifreeze these days as standard, so the manufacturers own recommendation is certain to contain such inhibitors. The risks arrise when peoiple try and save a few bob by using industrial products intended for other uses than car engines (neat ethylene glycol, for example).
As I said in my previous posting, distilled or deionized water is actually very agressive (don't drink it!) and will really get to work in cooling systems containing multiple metals. In an engine with both cast iron and aluminium, the water will quickly eat away the aluminium by means of electrolitic ion migration.
Proper antifreezes/cooling water inhibitors contain ingredients that neutralize this process, and so successfully that many car manufactures have "sealed for life" cooling systems, or systems where they only need changing every 5th year.
If you are using an ethylene glycol-based regular car antifreeze, you've nothing to worry about, just mix it 50/50 with normal tap water. If, on the other hand you have obtained some neat e-glycol without inhibitors, I would definitely not use it in an engine with mixed metals (such as the BX). The same applies to using just plain water (as mentioned, de-ionized or distilled is even worse).
We all have a great deal of fun on the behalf of FORD (including Hal****'s) but they actually have very high quality requirements on their oils and cooling system liquids ( I wonder why?), products than match Fords requirements are often good value for money.
//NiSk

Post by **RichardW** » 12 Nov 2002, 18:52

Alan,
Have a look at this page:
http://www.babcox.com/editorial/tr/tr110046.htm
It seems to be a balanced and honest appraisal - although the usual caveats apply!
It seems that the pH is the important factor when it comes to corrosion protection (which is what you're looking for after all!), and so we should be monitoring the pH of our coolant and when it begins to drop we should change. I remember that some coolants used to change colour when they were spent - presumably on the basis of the pH. The coolant in my old TD had changed from red to colourless when the head gasket went, but that may have been co-incidental (it was still liquid at -18C in the freezer though)!
In your case, rainwater should be relatively pure - it has been evaporated so won't be carrying any salts - except those it has picked up whilst sitting in the tank. It is most likely to be acid when it falls (due to NOx and SOx in the atmosphere making nitric and sulphuric acids) but may have picked up some alkalinity when sat in your concrete tank, although I can't say so for sure! You could measure its pH to see.
It looks like OAT may be a double edged sword in older cars, so I would stick with EG in the 16V.
As to concentration from that link, and what I have heard before 50:50 should give you the best possible corrosion protection (and protect you JUST in case you get to see some snow some time!).
My own impression, and info from the link suggests that distilled/deionised water is no better / worse than tap water if used alone, but offers advantages if used with antifreeze as it doesn't swallow up a whole load of the corrosion inhibitors dealing with ions present in the water at the start.
So, in summary, I think:
Change coolant regularly if it's EG based
Use distilled water if you can, but tap is OK - just reduces the life of the coolant.
Use 50:50 mix - this gives best of corrosion protection, heat transfer and (for where it matters!) frost protection.
Keep the system full to prevent air ingress
Don't change to OAT additive unless the system is totally flushed, and keep an eye on the water temp (pump problems possible)
Now I just need to blag some pH strips from my Mum, and I can test away!
Richard