Pressure tester arrived today.

Not sure if I'm doing this properly - I've sxrewed the test cap on and tried pumping some pressure in, but the air escapes straight away before any pressure is built.

It looks like a simple device - screw on test cap, and connect pump with gauge.
I tightened the cap as much as I dare without breaking anything. Just sounds as if the cap is not sealing.

17452498088261490652287921097421.jpg
 
I'll have a look now.

I did get this picture of the rear valley gasket seal, it does look a bit wet there although is hard to tell with this tiny endoscope. It seems that signs are pointing to it being the source though.

If it is - is there a way to replace it that doesn't involve stripping everything off again?

Photo_2025-04-21 16_56_27_830.JPG
 
Update:

Found the right cap and pressurised to about 14 psi. Leak quickly started dripping from around the rear of the engine. Stuck the endoscope down and saw this:

Photo_2025-04-21 17_11_05_932.JPG

That looks like the culprit. Looks like coolant is leaking out of the bolt thread maybe? Feel like this is going to be a pain.
 
blue_cheese said:
Update:

Found the right cap and pressurised to about 14 psi. Leak quickly started dripping from around the rear of the engine. Stuck the endoscope down and saw this:

View attachment 339435

That looks like the culprit. Looks like coolant is leaking out of the bolt thread maybe? Feel like this is going to be a pain.
Click to expand...
If it's leaking out around a bolt thread, can the bolt be removed easily? If it can, drain the system, remove the bolt and dry the threads then refit the bolt with a coat of silicone or Locktite.
 
That pic looks like the valley gasket metal clamp. The bolt is nowhere near the coolant, so unlikely to be that.

The leak is most like one of the two coolant ports on each head. If I remember correctly the inlet manifold block the two rear ports, but has coolant flow from the front pair.

When fitting the valley gasket it really needs decent sealant around those ports, or the valley will leak.

1745257374722.png
 
I used some red RTV sealant around those ports, perhaps I made a bad job of it. Only one way to find out how suppose! 🔧

Can the intake manifold + fuel rail be removed without taking off the alternator/ps pump? That would save me a lot of time
 
It's not loads and loads to take off again is it? I mean, less than you did before.

I run a bead around both ports, and then all the way along the back of the engine, from one side to the other in one continuous run. Then put the rubber seal over the bead.

I've had it leak from there before....
 
Not a huge amount of work, but it would take me a few days as I'll be at work during the day, so only have an hour or two each evening (weather dependant).
Can I reuse the valley/intake gasket if I scrape off the existing sealant?
 
blue_cheese said:
Not a huge amount of work, but it would take me a few days as I'll be at work during the day, so only have an hour or two each evening (weather dependant).
Can I reuse the valley/intake gasket if I scrape off the existing sealant?
Click to expand...
I wouldn't re-use anything. I know it sounds like a waste.... but we're already leaking.
 
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