Recently I completed my XS with the 914 engine. It flew well but on the
third flight the engine failed and I force landed. Luckily there was not
too much damage to myself or the aircraft . Needless to say I am very
interested to understand why the motor stopped.[ I have left out the heart
stopping part in case there are Europa pilots out there with weak constitutions]
There are two puralator filters on the 914 set-up and the first conclusion
is that both filters became blocked.
After recovering the aircraft I dissconnected the carby line and attached a
clear tube . Fuel flowed but one filter/pump combination was delivering a
line of bubbles.
A second possible conclusion is that the bubbles accumulate somewhere un the
line and form a vapour lock.
The filters were at least partially blocked with fine material . I had been
obsessive with cleanliness in construction /fuel purity etc and had cleaned
the filters after the first flight with little dirt visible.
I have spoken to three other builders [ two here in Australia ] who have had
bad experiences with engine starvation .Not every one has had a forced
landing but they are 'Spooked ' by this problem.
The common thread is the puralator filter .They seem to be too fine and to
have too small a surface area so that when even a little material comes
along they choke. Additionally the are prone to leak air [ possibly with the
greater fuel pressure or the 914 pumps this is a new factor].
The factory tell me I'm a wimp.'Clean the filters regularly and all will be
well' 'We have had hundreds of hours on the puralator filter'
The other common thread is that ,in general ,the problem occurs in the early
testing time leading people to assume that it's builders fibre glass thats
causing the problem.. Is it possible that some of the tanks have a residue
---From the original building???
When I inquire I find a good proportion of builders have already abandoned
the factory puralator filters.
Does everyone know something I should know??
This problem has the capacity to harm the Europa . I would be pleased to be
guided by the experience of others.
Could any one else who has had a starvation problem put that experience on
this forum so that the problem and its extent can be grappled with.
I would be very grateful for any help in this matter. Kevin Pownall
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