What product would you use to fix a slight coolant leak on MK4 Golf

DJMK4 · 26 Jan 2010 at 10:37

Hi,

I have a MK4 Golf GT TDi (Y Reg) which has developed a slight coolant leak, its mainly leaks when under pressure, I have checked the seals which look OK.

I have read about using products which you put in to the system to block the leaking area. One I ran into was radweld.

Does anyone know if there is any risk of blocking the coolant system with this or causing more damage? Also, are there other brands out there which do the job a lot better?

I am selling the car in about 6-7 months and alread have to spend money on the car getting it sorted, I really dont want to spend more having the coolant system ripped out to be fixed.

If you could let me know.

Thanks

DJMK4

iaind · 26 Jan 2010 at 10:40

Does it need to be ripped out? Where's it leaking from?

I had a small hard to find leak in mine - turned out to be the heater matrix return pipe which runs under the sump, obviously got caught on a speed bump. Cost £40 to replace at a main dealer.

I'd try to locate the problem before you try stuff like that

Pete19s · 26 Jan 2010 at 10:41

DannyW?

Get it fixed properly or chances are its going to cause you issues before you sell it and cost you a lot more than it will now. I cant imagine it costing a fortune.

DJMK4 · 26 Jan 2010 at 10:45

I dont know where its coming from, I can't locate it, there is no leak underneath the car when revving stationary, cant see any other leaks, my mate checked too.

Firestar_3x · 26 Jan 2010 at 10:46

Checked the oil and coolant res, sure its not an airlock working its way out of the system?

DJMK4 · 26 Jan 2010 at 10:48

Checked the coolant res and as mentioned couldnt see any leaks from that.

iaind · 26 Jan 2010 at 10:49

Sheet of cardboard underneath the car (on a dry night!) and see where the drops are

Firestar_3x · 26 Jan 2010 at 10:49

DJMK4 said:
Checked the coolant res and as mentioned couldnt see any leaks from that.

As in any coolant in the oil and oil in the coolant?

I take it the heater gets super warm still?

DJMK4 · 26 Jan 2010 at 10:55

Firestar_3x said:
As in any coolant in the oil and oil in the coolant?

I take it the heater gets super warm still?

Cant see any oil in the coolant res but not sure about vice versa.

What happens is the car warms up, water temp as normal when fully warmed, I can feel the heaters working as the should in the car but half way through my journey the air starts getting colder even though the water temp is still normal.

DJMK4 · 1 Feb 2010 at 15:38

Bit of a thread revival this one, I have found some pinkish residue (only a small amount) around the filler cap and on some of the joints on the plastic coolent res container, in addition, I have found the same pinkish dry residue on the side of the engine on the passenger side.

Does this indicate that the coolent or head gasket is leaking? Its worrying me abit

The AA came to sort my battery out earlier, he stuck a pressure pump in and put some pressure through it but couldnt see any leak. As he came out to look at my battery he couldnt stay very long.

lordrobs · 1 Feb 2010 at 15:45

Chuck an egg into it

DJMK4 · 1 Feb 2010 at 15:47

lordrobs said:
Chuck an egg into it

`
Was going to try this, but was going to use something like K-Seal.

Can anyone comment on the leaking I found on the engine though?

Pink Dry residue, also found by the filler cap.

Matt82 · 1 Feb 2010 at 15:47

haha i was jsut about to say an egg. dumping rubbish in the system really isnt a good way to "fix problems".

just look for the pink drops and cure the leak.

judging by what you said it wants a new coolant flange on the side of the head

james.miller · 1 Feb 2010 at 15:50

Pete19s said:
DannyW?

sounds similar hey?

TigerUK · 19 Jul 2012 at 07:16

old thread i know. I got the same problem, losing about 150ml coolant a month. I've ordered UV dye and uv torch. its safe to pur a little uv dye in the coolant. Then wait 2/3 hours or come back later at night and shine the uv torch, it should tell you all.

hoping to find some leaks, leaks are good, better than internal "leaks" where coolant i dripping into the engine which can heat up and cause steam explosions and you're looking at bigger issues.

Matt82 · 19 Jul 2012 at 10:33

hi there

which engine do you have?

mine actually sprung a leak this week (192k miles, 12 years old)

flange on the side of the head. £9 from vw, plus new seal and clip for temp sender.

i changed the expansion tank too... now its good as gold again

Brookert · 19 Jul 2012 at 10:43

iaind said:
Sheet of cardboard underneath the car (on a dry night!) and see where the drops are

Wow, that is so simple yet clever!

miniyazz · 19 Jul 2012 at 12:21

Brookert said:
Wow, that is so simple yet clever!

Difficulty is when you notice the drips don't drop straight down, they run a convoluted path down tubes (and off under engine sound proofing, if you've left that on).

Fixed a significant leak in mine - it was the thermostat coming out, rammed it back in with some silicon paste and we're all good

Matt82 · 19 Jul 2012 at 12:38

or if you have an undertray

with an undertray though the engine bay stays dry, which makes the leak easier to spot.

with golfs being predictable theyll only ever leak from a few places too

TigerUK · 20 Jul 2012 at 00:00

the cardboard under the car method... if someone like me is losin 150ml a month works out 5ml a day which isn't much at all, wouldn't the coolant just evaporate before you spot it or will it leave a noticable "dye" on the cardboard?

Hopin the UV method will work better because UV dye is almnost impossible to get off once you got it on.. will light up the road under with a UV torch.