OMC 3.8 distributor

[Rosbullterrier]

Just overhauling distributor in final engine rebuild - I'm thrown by the advance weights appearing to be clamped stationary by a plastic collar.
My manual does not mention this.
Is this correct? Why should it be so?
the two tags say:
6269951 prestolite IBM 7014 4 N
and:
MARINE SAE - J1171

 

[Howard Sterndrive]

Re: OMC 3.8 distributor

the holes are slotted so the weights can move, they aren't held stationary.

 

[cr2k]

Re: OMC 3.8 distributor

6269951 is the OMC part #

Prestolite is the Mfg.

IBM 7014 4 N is a universal stock number (pre bar-code days)

MARINE SAE-J1171 tells you it is USCG Approved for Marine Applications in an enclosed space. (covered engine)

The collar rotates clockwise about 8-12 degrees when the weights move outward against the springs (very slightly) advancing the timing as the RPMs increase.

Under the felt pad in the hole on the top should be a screw that will allow you to remove the top piece to clean and grease the pivot bushing under there. Trailer bearing grease works well there.

Do clean and grease the pivot and slide surfaces with White Grease.

The distributor shaft bushing itself is lubricated by the oil splash and vapors from the lifter valley. It can be cleaned and oil applied during reassembly.

 

[Rosbullterrier]

Re: OMC 3.8 distributor

cr2k - 'screw that will allow you to remove the top piece' - is the top piece the six lobe distributor cam?
Under the felt pad in the top of this piece, is the inner shaft with a spring clip in a groove - no screw.
The plastic collar over the weights is held in this cam assembly in a slot. If you are saying the plastic collar and cam assembly should be free to be moved by the weights - then this assembly must be seized on the shaft.

There are two engines - neither cam assemblies rotate so I presume both must be seized.
Trouble is, if I use heat to free them on the shaft, the plastic collars will be destroyed. These distributors maybe are so old that parts are no longer obtainable!!
However, thank you for the explanation of the works.

 

[Rosbullterrier]

Re: OMC 3.8 distributor

cr2k, gradually loosened the distributor cam lobe part, removed and cleaned it, lubricated - all works v. well now!!
Thankyou
Andy