I bought a 1995 Chaparral with Merc 350 that the previous owner didn't winterize so I'm replacing the engine. My neighbor has a newer Vortec 350 and since it's from a truck it had an electric fuel pump. It does have the plate covering the hole where the mech fuel pump would go but I haven't pulled it off yet. I called my local machine shop and asked if they could drill out the hole for the rod that goes up to the cam but they said they can only do it if the hole was "started" or some sort of indication on the block as to where the hole would be. They have a jig for a 4.3L but not the 5.7L... They say the drill bit for both is the same, but without the jig they need some sort of indication as to where to drill the new hole.
I'm assuming GM wouldn't have punched the block or even started a pilot hole since they weren't using mech fuel pumps in the late 90's but they did keep the plate...
I'm curious if others that have drilled the rod hole have seen a punch or pilot hole where the rod to the cam goes... Or know some way of drilling this hole without a proper jig.
I'm assuming GM wouldn't have punched the block or even started a pilot hole since they weren't using mech fuel pumps in the late 90's but they did keep the plate...
I'm curious if others that have drilled the rod hole have seen a punch or pilot hole where the rod to the cam goes... Or know some way of drilling this hole without a proper jig.
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