NB8B minor coolant leak

[aviper4u]

Hello,

I have noticed coolant going astray albeit very slowly...

Last night after coming home I had a look and it seems I indeed have a leak which seems to be the water pump as it is coming from behind the main front crank pulley...

It has less than 130K and I changed the water pump along with a timing belt kit and drive pulleys at 99K about 8ish years ago. Is the water pump (GMB) failing as I perceive to be a little early normal or is there any other things I should check.

Hopefully this weekend I can intake tube off and have a closer look unless its something simple.

Below are some picks and the thing on my finger def smells like coolant hehe












Thanks everyone!!!

[lonesailor]

Since you have only done around 30K in "8 ish" years and the leak appears to be from the waterpump ,that's where I would be looking . Perhaps the belt was over tightened or sitting in the same spot for extended periods could have damaged the seal faces or the bearings could have corroded, Ensure that the leak is not from the small bypass hose or its hoseclips first.There is the small hose which feeds the oil cooler under the oil filter down there nearby too which is easily overlooked.

[aviper4u]

Ensure that the leak is not from the small bypass hose or its hoseclips first.There is the small hose which feeds the oil cooler under the oil filter down there nearby too which is easily overlooked.

Hmm its possible I screwed it up though I've done drive belts on other cars with out issue...

This bypass/oil cooler hose you speak of, what needs to be removed to inspect it as last time the motor was hot I tried to have a look around but couldn't spot anything other then my photos.

Thanks for replies

[RS2000]

There are 2 small hoses into a tee on the underside of the thermostat housing. Use a small 'telescopic arm' mirror & torch to have a good look.

[aviper4u]

just got back and had another look..
that's the thermostat housing yea? and it seems it isn't easy hehe





thanks all enjoy your weekend

[1600Dave]

That is indeed the thermostat housing.

I had very similar symptoms to yours, a very slow leak dripping down onto the crank pulley. Ended up being the "T" shaped pipe coming out of the thermostat housing that the hoses attached to had corroded to the point it had a pinhole leak. The one on my spare engine (see pic below) was also pretty sad looking. Unfortunately, if it is the metal pipe, its actually cast into the thermostat housing, to replace it you need a new thermostat housing.

Because I'm cheap, I ended up making a new pipe arrangement that was threaded, drilled the old one out of the thermostat housing and tapped the housing to take my new setup.

Or if you're lucky, it may just be one of the hoses.

IMG_0341 (2).jpg

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[aviper4u]

well done on your repair work

unfortunately the pics i posted yesterday were of my actual cars thermostat housing which when touching the t-connector was dry...

I just need to get a new woodruff key and make sure my local parts place has the parts available before i start pulling it apart

[Mr Morlock]

A leak somewhere. Wipe clean / drive- recheck / tighten fittings and or check hoses etc/ retest does it work. Its not likely a really big issue.

As for 1600 Dave- cheap fix ? I don't think so - for that you need skills no how and patience.

[RS2000]

You probably know this aviper4u, but in case you don't, a leak from a worn water pump mechanical seal comes out the bottom of the circled passageway. You should be able to tell if that's the problem before fully dismantling.

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[aviper4u]

Cheers for the replies and pics

I wanted to make sure I sourced a new woodruff key and make sure local parts place has stock of pump and timing belt kit and drive belts as I may take of the timing gear in case I did another timing belt kit again...

What are people thoughts on changing the full timing belt kit or don't bother as its less than half its life kms wise anyways? or just change bad pump if it is indeed that and don't touch timing belt, pulleys and oil seals etc

[aviper4u]

I've finally had a chance to open up the font of the motor to find the small coolant leak...

It seems to be leaking from the sealing gasket.

Advice: If I check nip up the bolts will it stop the leak or as already leaking the gasket is screwed forever?









Thanks as always

[Mr Morlock]

same rule always- if the fixing screws / bolts are loose then tighten them but over tightening in say alloy can strip a thread. Gaskets are there to seal so if the gasket is cactus then it will have to be replaced. A vehicle I have was leaking from a number of sealing areas- diffs gearbox etc and that came about from old age and replaced seals etc fixed it.

[RS2000]

Have a look at my photo a couple of posts up. Circled in yellow is the drain passage for a worn mechanical seal. You need a new pump.

[aviper4u]

@rs2000
Just had another look at your pic compared to my situation and the shaft seal and the actual pump body itself has no staining. All the staining is below the actual pump so it must be the sealing gasket right?

In saying that could something be warped because of track days?

Thank you all as always

[RS2000]

It's the internal mechanical seal, not the shaft seal.
When the mechanical seal is worn the coolant will come out the bottom of that passageway circled (just as yours is). It is a weep or vent hole & is not gasketed in that area. It prevents coolant getting into the bearings. A small amount of seepage is ok, but a leak indicates wear.
Cheers