Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

[Doctor Gollum]

Lift the carpet in the drivers footwell and report back...

[tunnie]

went to check again at lunch, it's dropped a bit since leaving for work. Was splashing around above the cold line by a fraction, now it's below the cold line by about 1/2 cm or so.

Spotted a drip of fluid, but think that was for air-con water, dropping around level with pre-cat on passenger side.

[Migv6 le Frog Fan]

I recently had coolant dropping myseteriously. Turned out to be the rubber washer on the underside of the header tank cap disintegrating and allowing some to escape. Fitted a spare cap and problem solved. Worth checking as an easy simple diagnosis / fix.

[tunnie]

Thanks.

It did cross my mind, I had a good look at underside of the cap. It looks good and solid, no obvious signs it could be degraded.

Did yours look broken/cracked underneath?

[Migv6 le Frog Fan]

Yep, plus the first clue was little bits of black rubber in the header tank. 
A crack at the header tank neck isn't uncommon though, and more difficult to spot. 

[tunnie]

New cap inconclusive, initially I thought the problem had resolved, it appears to have lost less over 60 mile return trip to work. But I think it has dropped a bit, will know more after tomorrows work run.

However I pulled up carpet in passenger footwell, it appears damp and I can see traces of water. Can't tell if it's coolant, also the sponge area around this wiring loom also feeds damp. 




Scuttle area clean and dry, never had any issues as it never gets clogged around here.

[Doctor Gollum]

Taste it.* Coolant is easily distinguished from stale water.

The fact it isn't pink suggests that it's rain water...

Scuttle, sunroof drain, hole in bulkhead, aircon drain etc, etc...

*Obviously drinking a litre of either is a bad idea, but the pinky dip is a useful guide

[tunnie]

Another 60 miles after topping up this morning and no drop in coolant, wondering if it’s the bottle.

Putting my ear close to the header tank, I can hear a faint hiss from cap.

I do appear to have some loss, but not as bad as before new cap went on.

[dave the builder]

you could try mixing some dilute washing up liquid in a spray bottle
gas /air  leak style 
maybe a hairline crack or leaky hose clamp

[tunnie]

you could try mixing some dilute washing up liquid in a spray bottle
gas /air  leak style 
maybe a hairline crack or leaky hose clamp

Good idea that, I’ll spray some around header bottle area. 

[Doctor Gollum]

you could try mixing some dilute washing up liquid in a spray bottle
gas /air  leak style 
maybe a hairline crack or leaky hose clamp

Good idea that, if I get time, I’ll spray some around header bottle area. 

[tunnie]

Hummm, stange this.

Last week I put a couple bottles of food colouring dye in, to try and trace the leak. It did 3 return trips to work (so ~150 miles), without using a drop of coolant. Note the trips were free flowing, still holidays so lighter on traffic.

Spent an hour on Saturday with car on ramps trying to locate leak, without luck.

Drive it to work on Monday and we had grid lock, due to traffic issues. 2 lanes out on M3 and local roads all blocked. So ended up parking for ~30 mins and doing work on laptop before carrying on, but still very heavy traffic. Not a great run back either!

Check coolant level at home and half the header tank was gone.   

Going to check at lunch for signs of colouring dye, but still no pools under the car or anything. Inspections following all coolant hoses showed no sign of previous leaks.

it appears excessive idling is causing it to drink coolant. 

[aaronjb]

The coolant temperature will go up significantly in slow traffic compared to free moving traffic, so perhaps it's coming out of the cap/tank because it can't maintain 13psi (or whatever pressure it's meant to)? Can't remember if you've already changed tank & cap, though..

[tunnie]

The coolant temperature will go up significantly in slow traffic compared to free moving traffic, so perhaps it's coming out of the cap/tank because it can't maintain 13psi (or whatever pressure it's meant to)? Can't remember if you've already changed tank & cap, though..

Yes new cap, I have suspected bottle but after inspections it's all dry. Popped bonnet straight after work/home runs, it's all dry around there. Unless it escapes in a vapour type mist 

I would have expected with dye to see traces now 

[Nick W]

You've used several foolproof methods to prove there isn't an external leak.
It has an internal fault, and a rotten head gasket is most likely. It's doing almost exactly what mine did: fine on a run, but short low speed urban journeys cause the water level to drop noticeably.