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K Smith
 
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Default Hydrolock mystery continues........

Gould 0738 wrote:
All the above Chuck but also, suspect a leaky injector, they can drip
fuel, even more so if you had full tanks for your trip.

Please tell us the outcome of the post Perkum.



OK, I'm stumped. How would a leaky injector, (dripping fuel) fill #1 cylinder
with water? If an injector had been leaking fuel into a cylinder, it would not
have cuased this failure, (unless there's a factor I'm failing to consider).
The engine locked on water, not fuel.....important point is that it ran for
15-20 seconds after start up, and it would not have done that if a cylinder was
completely filled with fuel.


Sorry Chuck I was unaware you were positive it was "water" that caused
the trouble & I'm sure you had mentioned it ran for what? 20 seconds??

I only suggested the injector because it can happen, your pump operates
at 3 levels, the lift pump will draw fuel from the tank & give it to the
pump at about 7psi, the next stage is a vane pump inside the injector
pump which takes it to a circulation pressure of about 100 psi (varies
with power & revs) the last stage is the pistons being pushed together
to create the injection pressure, say 2000 psi.

If fuel is available even at slight positive pressure it will find it's
way through the system till it gets to the injectors (all the valving is
to stop it going the other way) & if you have an injector where the
pintle is worn it can drip fuel. Especially if your full for holiday
trip tanks have a head of pressure up to injector level.

Assuming you have a CAV system (Perkins likely or the similar Bosch)
the standard test is;
(a) Normal pintle injectors, subject the injector to a pressure of 10
ats below opening pressure (on a jig), after 60 seconds the fuel stain
produced on blotting paper held below the nozzle shouldn't exceed 12mm
in diam.

(b) Pencil injectors are allowed 3 to 20 drops of fuel over 15 seconds;
in the same premises.

It's not relevant because as you say you know it was water in there &
as I said all the above, but whatever get the injectors serviced before
you trust them on your rebuild!!!

K