Coolant in chassis drain holes?

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jules
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Coolant in chassis drain holes?

Postby jules » Fri Aug 10, 2012 5:57 pm

Hi Guys,

I seem to be losing coolant. There is a damp area on the block around the heater hoses, but no drips.
However I have noticed what looks like green coolant in the passenger side front chassis drain holes?

That's weird? I'm thinking maybe the heater core is failing?

Thoughts?

Thanks
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spikes
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Re: Coolant in chassis drain holes?

Postby spikes » Fri Aug 10, 2012 8:44 pm

heater hoses connections or heater core. Go get some toilet paper and neatly fold it up around underneath the heater core area, toilet paper is easy to identify leaks as it swells up when wet giving a clear indication of where its leaking.

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Re: Coolant in chassis drain holes?

Postby greenMachine » Sat Aug 11, 2012 11:19 am

jules wrote: I'm thinking maybe the heater core is failing?


My bet. Check the carpet, if it feels damp ... no need to go any further :( .

Unless you have recently changed the core, just rip the lot out and replace it - core, pipes, hoses ... it is not a fun job, but one that comes to all older cars sooner or later.

From viewtopic.php?f=29&t=43127&hilit=+core

greenMachine wrote:OK, a more considered post.

Have a look up under the dash - see any signs of water/coolant? Feel the carpets on each side, checking for dampness. How much water are you losing, that is what you are looking for in your carpet. Is the coolant rusty, you may be able to see staining on the carpet.

When mine went, we replaced the carpet as the staining/smell was too bad but YMMV.

This is not a trivial exercise, you want to be sure it is the radiator core that is leaking before you commit to replacing it. We pulled the dash out to get at the heater, but I believe that you can do it without that although I don't know the details - search here and on the big board. Since we were replacing the carpet it made sense to gut the interior, so I never looked at doing it any other way.

Watch your coolant level like a hawk, mine went from a slow leak to a gusher over a hundred kms or less. I am not kidding when I say the first step is to bypass the heater, and isolate the problem while you organise the fix.

Good luck.

:mrgreen:


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Re: Coolant in chassis drain holes?

Postby jules » Mon Aug 13, 2012 8:21 pm

OK, the floor on both sides is dry. I seem to be emptying the recovery tank of coolant weekly. It is not leaking BTW. The coolant is fresh, I'm pretty fussy about this sort of thing. The radiator cap was replaced 6 months ago.

Can't see any drips under the car. Radiator also seems fine. The only suspicious area is at the back of the engine. Maybe the rear heater hose to block water outlet connection is dodgy, or even the water outlet at the back has a failed gasket?

The hoses are less then 12 months old and the temperature gauge is steady.

I might have to do some more inspecting on the weekend and remove the coil packs and have a good look at the back?

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Re: Coolant in chassis drain holes?

Postby timk » Mon Aug 13, 2012 8:32 pm

Time for a dodgy day! :P

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Re: Coolant in chassis drain holes?

Postby JBT » Mon Aug 13, 2012 9:01 pm

jules wrote:I might have to do some more inspecting on the weekend and remove the coil packs and have a good look at the back?

There is a small cap and I think the ECU temp sensor at the back of the head - mongrels to get at with the engine in the car. Pic of cap attached.
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Re: Coolant in chassis drain holes?

Postby greenMachine » Mon Aug 13, 2012 9:45 pm

jules wrote:OK, the floor on both sides is dry.

That is good.

jules wrote:I seem to be emptying the recovery tank of coolant weekly.

That sounds like the system is pressurising - head gasket? Is the overflow from the reservoir the source of the coolant in the chassis rail? (EDIT: probably not if it is on the passenger side :roll: )

Looking at the back of the head, the welsh plugs, and the heater piping at the front will also help rule in/out external leaks. However I don't like the sound of the reservoir having to be emptied - that is not something I have run across before, adding yes, but not having to empty it :shock: :?

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Re: Coolant in chassis drain holes?

Postby NitroDann » Mon Aug 13, 2012 9:50 pm

I think hes saying that the motor is using water and its emptying the reservoir.

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Re: Coolant in chassis drain holes?

Postby greenMachine » Mon Aug 13, 2012 10:55 pm

NitroDann wrote:I think hes saying that the motor is using water and its emptying the reservoir.

Dann


:oops:

My last comment is to suggest that you start the car, let it get to operating temperature, and go looking for the coolant to appear - maybe put some paper/cardboard under the car?

:mrgreen:
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Re: Coolant in chassis drain holes?

Postby jules » Tue Aug 14, 2012 9:53 pm

Correct. I'm filling the reservoir weekly. I assume it's going into the radiator. I had not considered the rear welch plug. Hope it's not that :cry:
With the car running and hot there is no drips. Maybe it gets dissipated on the top of the gearbox if it drips there.

I might see if I can get hold on one of those little mirrors on a bendy stick :idea:

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