Coolant disappearing, but temperature is fine...

Coolant disappearing, but temperature is fine...

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Discussion

lagori

Original Poster:

52 posts

104 months

Saturday 2nd July 2016
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I've recently bought a Jeep Cherokee 2001 and one of the first things I noticed was that the coolant reserve was running on nearly empty. I had limited time so topped it up with water, anticipating a flush and refill when I can spare a couple of hours. Then I did a pretty substantial journey being sure to watch the temperature - the car ran absolutely perfectly so I thought nothing more of it.

I checked again today and the reservoir is again pretty much empty so clearly the liquid is escaping somewhere but here's the rub - I don't have any clear leaks, inside the engine bay, on the floor when parked or in the cabin in the footwells. I've done near 1000 miles and the temperature has been perfect and the car has run generally great (aside from the heater has been rubbish which I assume is related). There has been the odd morning where I have had to apply the gas pedal to get her going, but not every time. There is however the slightest light brown on the oil cap so my assumption is that the leak is there. My assumption is that its a head gasket issue, but before I start down the road of what I hear is a painfully tedious job (this would be my first 'major' mechanical fix - even if its not that major), what else should I do to ensure it isn't something else? If it is a head gasket issue - can anyone recommend a list of spares and / or parts beyond the gasket itself that I should have just in case? My plan would be to flush the coolant, then replace the gasket and then the spark plugs for good measure.

Appreciate the insight from those more experienced than me.

PositronicRay

27,012 posts

183 months

Saturday 2nd July 2016
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Get a sniff test and pressure test done before weighing in with spanners.

lagori

Original Poster:

52 posts

104 months

Saturday 2nd July 2016
quotequote all
PositronicRay said:
Get a sniff test and pressure test done before weighing in with spanners.
A sniff test?

marshalla

15,902 posts

201 months

Saturday 2nd July 2016
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lagori said:
A sniff test?
Gas test to see if there's any sign of exhaust gases in the coolant.

lagori

Original Poster:

52 posts

104 months

Saturday 2nd July 2016
quotequote all
marshalla said:
Gas test to see if there's any sign of exhaust gases in the coolant.
Ah right, thanks. OK, so go to a garage to get someone to take a look. Shame, but no worries.

anonymous-user

54 months

Saturday 2nd July 2016
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Was it purchased from a trader/dealer? How long ago did you buy it?

lagori

Original Poster:

52 posts

104 months

Saturday 2nd July 2016
quotequote all
bmw535i said:
Was it purchased from a trader/dealer? How long ago did you buy it?
From a dealer about 5 weeks ago.

anonymous-user

54 months

Saturday 2nd July 2016
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lagori said:
From a dealer about 5 weeks ago.
Have you spoken to them about it?

finishing touch

809 posts

167 months

Sunday 3rd July 2016
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I had a car once with a microscopic hole in the heater matrix. Water/coolant would escape as a tiny jet of steam, never any liquid to spot.

With the heater set to "hot" and "demist screen", and windows closed, there would be a slight smell of antifreeze in the car.


Paul G

LarJammer

2,237 posts

210 months

Sunday 3rd July 2016
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You really need to get it checked by a garage before jumping to wild conclusions. The first (of a few) faults that popped into my head was a failed expansion tank cap.

E-bmw

9,219 posts

152 months

Sunday 3rd July 2016
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Ok, let's go through what you say point at a time.

You say the expansion tank was low twice & you have had to top it up twice, but there has been no temperature issues.

As the expansion tank has only been low (not empty) your cooling system was still full each time (the expansion tank is just an "additional" bit of water used to allow for volume changes due to temperature differences when in use) so you wouldn't necessarily get temperature issues from this.

You say the heater isn't very good, have you tried to bleed the system of any airlocks?

You obviously say that there is water going somewhere, but no sign of external leaks, as you know it is going somewhere, so the likely candidate is internally into the combustion chamber.

This COULD be also backed up by it being difficult to start occasionally as you say, and a sniff test will help with further investigation.

My advice would be to check the system is air-lock free, mark the level when cold, take it for a significant drive until fully hot, check the level when hot, then leave it to cool & see if it goes back to the same level.

If it drops lower with no sign of leakage get it checked out by the garage you bought it from & make sure they know what you have done & what you suspect, but do it soon.

lagori

Original Poster:

52 posts

104 months

Sunday 3rd July 2016
quotequote all
bmw535i said:
Have you spoken to them about it?
No, mainly because the guy has been away, but in addition its about 150 miles away so not really an option to drop it back and ask them to sort.

lagori

Original Poster:

52 posts

104 months

Sunday 3rd July 2016
quotequote all
LarJammer said:
You really need to get it checked by a garage before jumping to wild conclusions. The first (of a few) faults that popped into my head was a failed expansion tank cap.
Precisely why I thought to post the question, thanks.

E-bmw

9,219 posts

152 months

Sunday 3rd July 2016
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lagori said:
bmw535i said:
Have you spoken to them about it?
No, mainly because the guy has been away, but in addition its about 150 miles away so not really an option to drop it back and ask them to sort.
To state the obvious, your reluctance to get in touch may well cost you a very large bill then, rather daft IMHO.

At least get in touch, the warranty they have given you (I am assuming they did) may well mean you don't have to take it to them.

bigkeeko

1,370 posts

143 months

Sunday 3rd July 2016
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Diesel or petrol? Orvis model?

lagori

Original Poster:

52 posts

104 months

Sunday 3rd July 2016
quotequote all
bigkeeko said:
Diesel or petrol? Orvis model?
Petrol 4.0. Not Orvis, 60th Anniversary.

lagori

Original Poster:

52 posts

104 months

Sunday 3rd July 2016
quotequote all
E-bmw said:
To state the obvious, your reluctance to get in touch may well cost you a very large bill then, rather daft IMHO.

At least get in touch, the warranty they have given you (I am assuming they did) may well mean you don't have to take it to them.
I will do, as I say - he's been away. No warranty unfortunately (why the assumption?).

E-bmw

9,219 posts

152 months

Monday 4th July 2016
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Simply because you stated it was bought from a dealer, I have never bought from a dealer without a warranty.

anonymous-user

54 months

Monday 4th July 2016
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E-bmw said:
Simply because you stated it was bought from a dealer, I have never bought from a dealer without a warranty.
Even without one, you still have recourse. That's if you speak to them of course.

E-bmw

9,219 posts

152 months

Monday 4th July 2016
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Hence why I said he is risking a big bill by not getting in touch with them.