How do i flush my cooling system

[Smokey]

I have been having heater probs and have been told its prob the matrix as on hot i only get luke warm air, and was told as a temp measure to flush the system, so i had a look in my expansion tonight and the water is sh*tty brown and i squeezed the pipes leading throu the bulk head from the bottom of the expasion tank and it was crunching as if there is sh*t on the inside of the pipes, so am hoping this is why im getting heater probs!

I went and bought some SPEED flush today from Halfords and was wondering how do i go about flushing my system?

Am gonna do this tomorrow so help muchly appreciated!!

I will buy a haynes one day and stop hassling ya with silly little things like this!



smokey

 

[scotty16v]

I had the same problem on mine, the water had gone brown because the fan had failed on the previous owner, is your fan working?

First thing to do is clean out the expansion tank, take this off, fill it with small stones and put some alloy wheel cleaner in it and shake it like theres no tomorrow, then fill it up again and repeat, make sure you get all the stones out and it is rinsed before you reconnect.

Way to flush it is to take off the bumper on the front of the car, then if your looking head on at the car, the bottom hose on the radiator is on the left, it is held on by a pig clip, get a jubilee ready to replace it else youll regret that.

With the bottom pipe undone, pour water through the expansion tank until it starts to run clear out the bottom, then put the pipe back on , fill up with water and run the car for 10 minutes.

Then repeat the process as the water will be brown again!

I had to do this 6 times before it ran clear, but once its done your laughing.

The other bit of advice is watch you dont spill any water outside the expansion tank, i did this while the ignition was on and it ferked my starter motor, get a funnell £1.56 from homebase.

 

[spirez]

do you lose a lot of water as well? my whole system was draining after 2 days but i re-sealed the water pump yesterday. im yet to re-fill it and flush the system but ill let you know what happens.

 

[Mike@Rentech]

A Common problem with Renaults , I have tried to flush a few out but in the end it is best to replace the heater matrix and replace coolant.

The heater matrix is not that bad a job to do, depending on what Renault it is, I would say it takes me about 2 - 6 hours to do from start to finish once , dont lose any fixings believe me you have to remove a fair bit most of the time.

 

[Smokey]

yeas fan is working scotty16v, do i need to drain the system b4 i take off the expansion tank? If so how? Is there a drain plug?

Spirez, no i dont seem to be losing any water its just really dirty!

Mike172sport, its a phase 1 clio 16v, i am going to try this then if that fails i am going to try to replace the matrix, but i dont seem to have a lot of time and i think that is going to take me ages so i will have to book a ay or 2 off of work as i cant do anything without my car!

Thanks for your help!

 

[scotty16v]

if you just want to clean the xpansion out first then just pull the bottom pipe of the tank off, but be careful where you are directing the water.

far as i could tell only way to drain thw whole system was bottom pipe on the radiator.

no need for a new rad though unless its knackered

 

[Dean]

right im going to do this as my water is brown as my cars bare at the min

no bumpers etc

im i right in thinkin expansion tank is the round bottle that looks brown on every ones valveR?

SO do i remove the big clip and pull the pipe of that goes into the radiator with a bucket there ready? let it drain, then refit it with a jubilee, then let it drain etc repeat process till clear?

and do i remove that brown bottle thing to clean it out?

thanks scotty

 

[Rajk]

dean you want the hose on the otherside, the one near the alternator, it is at the bottom of the rad, a real pig to get to and any tools to, the brown bottle is the expansion tank, dont forget to bleed the system of air when you put in new coolant, there is a bleed screw on the top passenger side of the rad, just above the big hose that goes to the rad

 

[Dean]

im a little confused now?

right

the hose on the otherside? is this the one at the bottom of the radiator theres only 1 isnt there?

what do i put back in? use water till its completly clean them a mix of antifreeze and water when done?

to bleed it off air do i have to do this every time i flush it and refill it with water? and how will i know when all the airs out etcv?

sorry 4 all the qs!

 

[Scribbler]

How do i flush my cooling system??

A curry usually does the trick!

 

[Jim172CUP]

mmmmmm curry, chicken Madras please.

 

[Rajk]

there is only one hose at the bottom, sorry to confuse you.

Drain the water and then put it back on, run a hose through the system one from the expansion tank, fill up as normal and then bleed the air from the system, basically you will hear the air hissing out, then when the water comes out replace the screw, run the car until its hot with the expansion cap off and the fan should cut in.

if the fan doesnt cut in there is still air in the system, but it shouldnt be!

but if you only flush the system once the brown cr4p will come back, you need to get that speed flush stuff and run it in the car for a week. then do the above!

 

[Smokey]

he he now im confused!!

1:So i take the pipe off of the bottom off of the rad (its a pig)

2rain system into bucket (will a bucket be big enough?)

3:Get mums hose pipe and put in expansion tank (with hose still off of rad or do i put it back on?)

4:Keep doing this till water comes out clear

5ut hose back on bottom of rad

6:clean expansion tank with stones and water (or do i use alloy wheel cleaner?)

7:Fill system back up and add my SPEED flush

8:Bleed any air out of the system

9:Run engine for 10 mins or until warm with speed flush in

10:Repeat whole process again but without adding the speed flush in part 7!

And Hey presto!! Right??

Is this ok? and do i really have to take the bonnet & bumper off?

 

[Smokey]

bttt

 

[Dean]

bonnet off? dont need to go that far mate!

i hope, il be doing mine at the weekend, im not having any problems that i know ff but the water looks sick!

as does the expansion tank1

 

[Smokey]

will be doing mine tonight hopefully if the rain holds off!! Thats a big IF!

 

[Rajk]

ok this is how i would do it

1. take the bottom rad hose off(until there is no water left)

2. take expansion tank off

3. put the rad bottom hose back on with new hose clip

4. get Mr hosepipe, there are three hoses that attach to the expansion tank, disregard the upper hose of the expansion tank and you will see two thicker hoses

5. put the hosepipe in one of the thicker hoses, you may have to hold it in place

6. run until the water runs clear out of the other expansion tank hose

7. swap over and do the same to the other thick hose, until water runs clear.

8. Now clean the expansion tank with stones and alloy wheel cleaner whilst its off the car.

9. Take off the bottom rad hose again to let out any water left in the system

10. Refix the bottom Rad hose again.

11 Put the expansion tank back on the car connecting all three hoses

12 Now put in the new mixed coolant until the expansion tank is half full

13 un do the bleed screw, letting the air out of the system and then replace the screw

14 Run the car( dont drive it ) until the fan kicks in and then put the expansion tank lid on, you are aiming to have a level of coolant between min and maxi

Job done, if you dont get this then get a haynes manual, run the car with speed flush in for about a week and then do this process, saves you doind it twice

 

[scotty16v]

yep...very thorough

 

[Dean]

rajk

nice 1 bruv, gonna get my ass into gear and do mine!

 

[Smokey]

Thanks rajk, i Will put rad flush in now then run it till the weekend and i will follow your instructions!

Im probably making a meal of and will find it easy when i give it a go! I found this when i changed my brake pads!

smokey

 

[Rajk]

its easy once you have done it a couple of times, best thing is to change your coolant every 6 months otherwise its starts to go brown again

 

[Smokey]

yeah thats what i thought, i put the speed flush in last night and am gonna do it on saturday so will let you know how it goes!

 

[Rajk]

cool look forward to it, gonna do the willy when i get it back!

 

[Alex M]

If you want to flush out the block more effectively, than flushing from expansion tank to radiator bottom hose, there is a drain plug on the engine block, although its a bit of a joke getting to it. It is tight in under exhaust manifold on drivers side of engine at bottom of block, a couple of inches from top of sump. Think it is a 16mm (common size on valvers, but hardly appears on other motors!

 

[Smokey]

Right started to flush my system tonight but it got too dark before i could finish so am gonna do it in the morning!

1 problem: Previous owner had snapped the bleed screw and glued it back together, while unscrewing it only the top part came out while trying to get the rest out i poked it inside the radiator by mistake! tw*t i know!!

Thing is how the feck do i get it back out again? Do i need to get it back out again?

Heeeeeeeellllllllllllllllllllllllllllllllllpppppppppppppppppp

 

[Rajk]

hmmm, the only thing i would say is try and flood the system with water in the hope it will come back out, but other than that you might have to take the rad off and get it taken to a RAD specialist, they can dimantle and re-assemble the RAD for about £60. Where are you based, there is a good rad place in Heathrow. Erm i think you may have to get it out otherwise it could block the cooling system and cost you more money at a later stage. If you want to know how to take the rad off, post up and i will explain how without taking the whole front end off.

 

[Smokey]

oh F it! What an expensive coolant change this is gonna be! There goes my Cambelt change fund!

The whole front is still off the motor Rajk, im finishing it off tomorrow hopefully!

If i take the inlet pipe off of the rad (one nearest the battery) will it come out there if i back flush the system?

Thanks Rajk your a star

 

[adiclio16v]

id buy a new rad think mine cost me about 100 quid from euro car parts and was lots better than the old one which mus hav been blocked

i also fitted a low temp fan switch an thermostat (from bb tuning) and did a flush

to get the plug out of ur rad ull prob have to take the rad off the car an try an shake it out of the inlet pipe hose connection

adi

 

[Smokey]

Mate i really cant afford a new rad!

Car is coming upto 130k and i think i really should get the cam belt done asap i.e b4 it gets to 130k!! As there is quite a bad whinning noise coming from my engine and have gone by BB performance tunings suggestion of CAMBELT TENSIONER or CAMBELT IDLER PULLEY so am gonna be looking at over £200 squid which i can barely afford this month and if i dont get it done at the end of this month i think i will live to regret it if it dont make another month! So i dont really wanna be forking out £100 on a rad if i dont need one just yet!

Thanks anyway

Smokey

 

[Dean]

im going to do mine some time soon, its just im not insured on the car yet so cant use speed flus as im not driving it round

also i looked at the radiator and where i thought there was a pipe there wasnt, but i did notice a large ish pipe going into it from the top on the passenger side, with a large green clipp, do i remove this and flush then replace with a jubilee

if the water is browny does this mean it doesnt operate properly?!

 

[adiclio16v]

maybe s/h rad then prob lots cheaper but better than ur high miler mine came out at 146k and was pretty fuked

cambelt shud be on its second change at 130k

browny water is rust u dont want rusty sh*te blockin ur cooling system up

 

[Smokey]

The pipe you need to remove is on the drivers side round the back near the bottom, its hard to see but trust me it is there!

Take this pipe off and direct it over a bucket and then undo the expasion tank cap, wait for a minute or 2 while the cooling system empties!

Then fill up a watering can with just water, pour some water into the expasion tank and let it flush out the bottom. Do this 3 or 4 times!

Put the pipe back on the rad and fill system back up again! Not too much just so tank is half full!

This is as far as i have got at the moment but i am going to finish it off in the morning!

Will update tomorrow!

Brown water is not good as it means there must be rust present!

Oh yeah i have been running car with rad flush in for the last 3 days and done about 100 miles with it in!

smokey

 

[Smokey]

Thats what i thought adi as it was changed at 68k

 

[Smokey]

What are BB tuning like? Is £157 all in a good price for the cambelt change not including the other 2 parts!

The other 2 parts, do they really need changing or are they trying to fleece people of there £££?

 

[Dean]

i dont know if my coolant had ever been flushed tbh lads

im going to do it 2moro hopefully

im going to have some real flushing to do i can see it now

 

[Dean]

also what do i fill it back up with

water anti freeze? 50 50

 

[Smokey]

Im gonna fillmine up 50 50 as winter is just round the corner!

Be careful taking out the bleed screw and putting it back in as mine has gone into the radiator!

 

[Dean]

i dont even know where it is!

i might leave mine for a pro u know lol

 

[Smokey]

bleed screw is on the passhger side at the back of the rad about 2 inches down!!

I cant get a bleed screw anywhere so am f**ked by the looks of it!!

 

[Fatherted]

dont know of anyones already suggested this coz i cant be arsed to read all thats been posted

the best thing to do is flush it & then replace to matrix as well

easiest way to flush the matrix is to find the 2 pipes that go to it through the bulkhead, disconect them both & shove a hose pipe up the one on the right , this will reverse flush it.

usually when matrixs get cloged up with crap is isnt long before they leak !!!