Part 43 Re-Fitting the Inlet Manifolds and Carburettor Rubber Sockets ...

Introduction ...

This page contains photos of the process of re-fitting the inlet manifolds and carburettor rubber sockets to a ROTAX 912ULS engine (built August 2006).



ROTAX 912ULS inlet manifolds and carburettor rubber sockets

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We make a start by fitting a new set of manifold o-rings ...

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ROTAX 912ULS inlet manifolds and carburettor rubber sockets

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Ensure that the recessed grooves that they locate in on the cylinder heads are clean and clear of FOD. Cotton wool buds can be handy for this job ...

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ROTAX 912ULS inlet manifolds and carburettor rubber sockets

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Torque the manifold bolts as per Heavy Maintenance Manual ...

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ROTAX 912ULS inlet manifolds and carburettor rubber sockets

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And do the same for the other manifold ...

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ROTAX 912ULS inlet manifolds and carburettor rubber sockets

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Next we can fit new o-rings to seal the join between the manifolds and the carb rubbers that the carbs are mounted on ...

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ROTAX 912ULS inlet manifolds and carburettor rubber sockets

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If you apply a thin coating of GP grease to the o-ring before locating it in it's target groove on the manifold this will help to ensure it holds it's position in it's groove whilst you are torque'ing up the carb rubbers. If this o-ring were to slip whilst you replace your carb rubbers then you could potentially have an induction leak which could mean a lean mixture and therefore a lean running engine which is not desirable ...

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ROTAX 912ULS inlet manifolds and carburettor rubber sockets

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Here is a new set of Rotax carb rubbers ...

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ROTAX 912ULS inlet manifolds and carburettor rubber sockets

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Fitted to the manifold. Note that the tightening ring with spacer has been removed to facilitate easier torque'ing of the carb rubber bolts. The tightening ring needs to be put on before carbs are fitted ..

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