Re: 1978 mercury 1400 reed block service
Im rebuilding my '78 1400 and i need advice about the reeds. Merc manual says reed leafs should not be preloaded or standing open (meaning not adhered to the block itself or standing open more than .007)...i have examined my reeds and several of the leafs are completely closed on each of the 3 blocks...i can take my pinky finger and push out on the leafs and when i do i can hear the leaf make a popping noise when it comes away from the block opening...What is the deal on reed block reconditioning?
If you can hear a popping sound the reed is sticking to the block. You are correct that the reed block can be re conditioned. With all the reeds removed rub the block on fine wet or dry emery paper lubed with oil. Mount the paper on a flat surface, glass or plexiglass. If you have stick on disks that are fine enough they work well too. Rub in a circular motion and change the position of the block in your hand. You are lapping the surface and will end up with a very smooth surface that will seal well without sticking.
Inspect each of the reeds, pay particular attention to the edges (look for cracks or kinks). Do not turn the reeds over they must be reinstalled the way they came out. Look closely at the holes in the neck of the reed, if the reeds have been improperly installed there may be a deformed portion that is holding your reed either open or pre loaded. I do not recommend trying to straighten a reed, if it is bent straightening it can work harden the material and lead to a failure down the road.
Boysen makes wonderful reeds....in this application though I would stick with Mercury reeds. When you re assemble the blocks do not over torque the nuts and bolts, the reeds will deform.
Don't forget to look at the inside of the reed block, if the ridges are mushroomed the block is toast and you will not get a smooth idle.
