Print

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

[SMD]

Serviced my car today and cleaned the breathers so took this opportunity to search for this small coolant leak. I was hoping it would be the HBV but that looks alright (although the view of it wasn't the best). Pic was taken with the plenum off (just for clarification).

What do you clever lot think?

[chrisgixer]

Yes

[SMD]

Wanna fix it for me?

[chrisgixer]

While the plenum is off , pressurise the system, usually by the throttle body coolant pipes and a foot pump as that's easiest, and see if any wetness appears.

While that is defo coolant residue, it could be from a previous leak, or a stat change.

But chances are, you have a leak in the valley. Either stat housing or oil cooler cover plate.

[SMD]

Thanks. Plenum is back on and jobs complete, tools packed away. I suspected that was the case but wanted to be sure.

To pressure test, are you suggesting using the coolant hose to plenum as a test point? Do I need an adapter of some sort?

[tidla]

Theres something somewhere in the guides. basically a tyre valve or air line connection fitted to a expansion cap, then connected to a pressure source of (1.5 Bar? please check).

While pressurized you can then visually check for the leak.

Done the oil cooler plate twice ( incorrect sealant) and now doing the thermostat for the second time( cheap crappy Q H thermostat stuck) so quality parts unless you like the practice.

[chrisgixer]

Thanks. Plenum is back on and jobs complete, tools packed away. I suspected that was the case but wanted to be sure.

To pressure test, are you suggesting using the coolant hose to plenum as a test point? Do I need an adapter of some sort?

It really needs pressure testing to confirm.

The method depends on what you have available. I know you have a foot pump. From previous posts.

The link below is for example only, but shows the sort of adaptors they sometimes come with. In red blue in the pic.

https://www.google.co.uk/shopping/product/229960147468043506?q=foot+pump+adaptors&bav=on.2,or.&bvm=bv.62922401,d.d2k,pv.xjs.s.en_US.ZfNDGiDE8KM.O&biw=1024&bih=649&tch=1&ech=1&psi=HvwtU7PLG8r30gWLoYHABg.1395522593423.5&ei=LfwtU6WMIeqM7QbkoYG4Bg&ved=0CLEBEKYrMAk

If the plenum is removed, which you will need to anyway, it means removing the the coolant pipes to throttle body. You can clamp one pipe with mole grips Orr pliers, and use the other to pump up the system with adaptor and foot pump.

Don't go more than 20psi though.

Then, once under pressure, its just a question of spotting where the coolant appears from, if at all.


If you have a spare coolant cap, its even easier if you can fit a shredder valve or push bike valve in it, with the appropriate pump.

Like I said, depends what you have available.


You could seal your mouth over the coolant cap and blow. While an assistant looks for the leak. Or just blow into the throttle body coolant pipes described earlier.

Just don't turn blue and pass out.

You get the idea. Doesn't matter how.

[JamesV6CDX]

Fully agree with Mr Gixer

Is your coolant level actually dropping, though?

If not, I wouldn't be too concerned, very much an as/when job

[SMD]

Coolant level drops very slowly. In fact, iirc I topped up once since I first noticed it a year ago   

Thanks for the advice Chris,  I did have those blue and red adapters, better go and see if I haven't lost them

[Webby the Bear]

That defo looks like coolant. However not a very big leak if not just remnants from a previous change as someone's already mentioned. Blowing in to the coolant tank does work 

Mine stat was leaking and made a reet mess with pouring coolant all down the front of the engine. If I was you I'd just recheck the torque of the stat housing bolts for now and see how it goes.

[SMD]

Blowing in to the coolant tank does work 

How do you do that?     By putting your beak inside the neck of the expansion tank?

[SMD]

I guess I should remove the injector rail and inlet before testing? I'm not quite sure how to do this and I don't see a how to in the maintenance guides.

[chrisgixer]

Blowing in to the coolant tank does work 

How do you do that?     By putting your beak inside the neck of the expansion tank?

Put your mouth round the coolant bottle neck as a seal. Blow, and hold it. Don't fart

[chrisgixer]

I guess I should remove the injector rail and inlet before testing? I'm not quite sure how to do this and I don't see a how to in the maintenance guides.

Ideally yes. But if the residue is anything to go by, the leak will appear in the same place. If the exact source of the leak isn't visible, then yes you'll need;

1) the injector inlet manifold out as one unit. 6 bolts and a magnet on a stick, plus undo the injector loom plug. It looks like it won't come out, but it does. Tilt it to one side and line the edge up with the slots in the head and it lifts out.
2) plastic inlet wedge. Several torx bolts.

Re use the old gaskets, they'll be fine.

Then you can see the oil cooler cover plate un obstructed.

[Webby the Bear]

See my coolant temp sensor replacement guide for a visual how to