Dirty Den Posted October 18, 2002 Share Posted October 18, 2002 I'd like to change the coolant in my crossflow this weekend. I've done a search and I'd just like to check my understanding, make sure I've got it right. The suggestions to do it seem to be: 1. Undo hose from bottom of radiator and drain cooling system, reattach hose. 2. Fill system with water/coolant. 3. To force any airlocks out of the system, jack car up at front, let car down. Repeat for rear of car. 4. Fill again as necessary. 5. Take car for drive to check. Is there anything I've missed? My cooling system is not a sealed system. How would the procedure differ for a sealed system? On a related issue, the person that I bought my 7 from suggested to use distilled water in the cooling system, but I've just added a tap water/coolant mix as I've needed to top it up - I've never used distilled water like that before . I guess using distilled water would stop furring from taking place - does anyone else use distilled water in this way? Should I do so when refilling the cooling system? TIA, Den 😬 - Self portrait - still unable to remove the smile! Link to comment Share on other sites More sharing options...
Silver 21 Posted October 18, 2002 Share Posted October 18, 2002 Den I only normally jack the front up, fill the system and then squeeze the bottom hose several times until air bubbles stop rising in the filler cap. With regard to what to fill it with I use the Comma pre mixed coolant (I think it changed its name recently) but its available in 5 litre containers from most independant motor stores Hope this helps but I'm sure another Xflow owner will be along in a minute 😬 Graham The not so New Competition Secretary, in fact already jaded 1700 Live Axle X/Flow, new pb at Curb, Loton Park and Shelsley Walsh in 2002 Link to comment Share on other sites More sharing options...
philwaters Posted October 18, 2002 Share Posted October 18, 2002 Den, Check if you have the little plug at the bottom of your rad - should be on the left side looking at the car from the front. Undo this (8 or 6mm Hex I think) and you can darin the coolant in a much more controlled manner - i.e not all over the floor! You can then take off the hoses if you want to to get the last free dregs out - I also take off the rad and wash it out in the bath - don't tell the misses that bit! Phil Waters You mean you can drive these? I thought it was just there to polish 😬 Link to comment Share on other sites More sharing options...
puremalt Posted October 18, 2002 Share Posted October 18, 2002 Where do you live? Is your water hard or soft? Normal antifreeze should do the trick in holding calcium in suspension so don't worry. If you want soft water use cooled boiled water as all the scale forming elements have come out in your kettle. If you use demin water as suggested it is very corrosive with a pH of around 4-5 so you would need to add a buffer or inhibitor to it anyway. Move to Wales, the water is soft!!!!! 😬 Dave Robertson Link to comment Share on other sites More sharing options...
Dirty Den Posted October 18, 2002 Author Share Posted October 18, 2002 Thanks for the replies so far chaps. If you use demin water as suggested it is very corrosive So it would be an idea to get that drained out, sooner rather than later then? I also take off the rad and wash it out in the bath - don't tell the misses that bit! So many blackmail opportunities, so little time... Den 😬 - Self portrait - still unable to remove the smile! Link to comment Share on other sites More sharing options...
Graham Sewell Posted October 18, 2002 Share Posted October 18, 2002 From memory, distilled water (which is what was originally mentioned in this thread)is pH neutral - otherwise all my old chemistry notes are rubbish. However, this stuff is hideously expensive when bought in a garage and I have never had a problem using tap water in the cooling system. Bear in mind that it is a sealed system and the amount of limescale present in a few litres of water replaced every x years is minimal. Otherwise central heating systems would give up the ghost very quickly. Low tech luddite - xflow and proud! Link to comment Share on other sites More sharing options...
Joe 90 Posted October 18, 2002 Share Posted October 18, 2002 I used to use distilled water, but gave up and it hasn't done any harm (and I live in a hard water area). I also don't bother with jacking the car up. What I do is allow it to stand for a while, after all there is always some other little job to do). Then I run the engine for a minute and refill. Then I run it until the thermostat opens, and fill it again. Finally I top it up after it's first run, when it's cooled down. 99,000 miles so far Link to comment Share on other sites More sharing options...
Dirty Den Posted October 18, 2002 Author Share Posted October 18, 2002 Graham, Oliver - thanks for the replies. I'll stick with the tap water Den 😬 - Self portrait - still unable to remove the smile! Link to comment Share on other sites More sharing options...
Big Brother Posted October 18, 2002 Share Posted October 18, 2002 Den, While the radiator hoses are off - use a hosepipe to back flush the rad. You will be surprised how much crud you can remove by doing this. Steve Se7en-Up! Less is more! Link to comment Share on other sites More sharing options...
Dirty Den Posted October 19, 2002 Author Share Posted October 19, 2002 Cheers Steve, do you mean stick a hose pipe in from the top and flush the crud out through the bottom, using the hose? I doubt I'll get around to it this time, I want to get the job finished tonight. I've got the car jacked up at the moment. Couldn't undo the plug that Phil mentioned, seems neither my 6 or 8 mm hex keys will undo it - looks like I need a 7 mm hex key, which just happens to be a size I don't have! ☹️ So, I had to undo the bottom hose and drain it out from there. Managed to not get it everywhere. The fluid that has drained out absolutely stinks - smells like fish. It's practically black too, which I'm sure isn't good. I'll leave it to finish draining out and then get back to it. Den 😬 - Self portrait - still unable to remove the smile! Link to comment Share on other sites More sharing options...
stevefoster Posted October 19, 2002 Share Posted October 19, 2002 Phil, I worry about you... Are you saying that you bath with your radiator sometimes... Do you brush it's fins with toothpaste and say good night to it too? ? I understand the don't tell the misses to be bit.... Now if it was an ali rad that would be different. They need looking after! /Steve My racing pics, 7 DIY, race prep. Updated often here Hants (North) and Berkshire area club site here Link to comment Share on other sites More sharing options...
Dirty Den Posted October 19, 2002 Author Share Posted October 19, 2002 I need a sanity check here guys. I drained the old coolant out into a tray, and it doesn't look like there's much there, although the system was topped up nicely before I drained it. I've now been refilling the system after doing the hoses back up. Using my trusty measuring tool (Robinsons fruit juice, 3 litre container) I mixed up a 1/3rd coolant, 2/3rds water mix, and refilled the system. Now I reckon I've put in the region of 2.5 litres in, but it seems that I might not have yet refilled it. I did the jacking up of the car thing, and also gave the hoses a little squeeze to help the airlocks out. As far as I can see, the garage floor isn't covered with coolant/water mix, so it must be going into the cooling system. Anyone know what the capacity of the cooling system is on a 1600 Sprint? Den 😬 - Self portrait - still unable to remove the smile! Link to comment Share on other sites More sharing options...
Joe 90 Posted October 21, 2002 Share Posted October 21, 2002 Hmmm My guess would be about 5 litres (a little less if you con't have a heater). I would run the engine to pump it all round, and then see what it looks like. If it's still black and smelly I would drain it again. 99,000 miles so far Link to comment Share on other sites More sharing options...
Dirty Den Posted October 21, 2002 Author Share Posted October 21, 2002 Thanks Oliver. Den 😬 - Self portrait - still unable to remove the smile! Link to comment Share on other sites More sharing options...
Paul McKenzie Posted October 21, 2002 Share Posted October 21, 2002 Graham, Throw away your chemistry notes! Distilled water is only pH neutral for a very short time - it absorbs CO2 very quickly to become a very dilute solution of carbonic acid with a pH of around 5 since there is no buffering salts in place. Don't even consider using anything but tap water, scaling will not be a problem even in very hard water areas, as unlike in your kettle, there is no concentrating effect due to the cooling system being essentially closed. Paul Link to comment Share on other sites More sharing options...
puremalt Posted October 22, 2002 Share Posted October 22, 2002 Thanks for the affirmation. I've been selling water treatment chemicals for 13 years, glad to know that i've not been fibbing to clients for this long. Link to comment Share on other sites More sharing options...
MartinW Posted October 23, 2002 Share Posted October 23, 2002 If you want to flush a x-flow cooling system, remember that the lowest point on the engine side of the system is on the nearside of the block, towards the back IIRC. Helpfully, it'll be behind your exhaust manifold/downpipes. It's a hex plug. If you've never removed it before you will get some deeply satisfying gunge out of it. Link to comment Share on other sites More sharing options...
guillaume Posted October 24, 2002 Share Posted October 24, 2002 carbonic acid - yikes! i recently flushed and refilled the rad on my xflow using halfords finest (well, most expensive) and the instructions said to use demin water . . . Are they wrong? Should i start again using tap water? Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now