Distributor Oil Passage Drilling
Thread Starter
Melting Slicks
Joined: Mar 2004
Posts: 3,472
Likes: 18
From: Lake Ozark, MO
Distributor Oil Passage Drilling
Would it be safe to copy the oil passges that are drilled into my Mallory distributor to the new Pro Comp? The Pro Comp has no oil passages drilled in the shaft. The Mallory has one small at the top and one larger at the bottom
Melting Slicks
Joined: Feb 2001
Posts: 3,330
Likes: 13
From: Europe , Luxembourg
Hi
The lower flange hole is to pressure lubricate the crive splines.
It should be Ok to copy the hole, watch the direction the distributor is installed in order not to spray past the drive gears.
Why there is a hole in the upper flange, beats me. I don't think you want pressure oil to spray up there.
Günther
The lower flange hole is to pressure lubricate the crive splines.
It should be Ok to copy the hole, watch the direction the distributor is installed in order not to spray past the drive gears.
Why there is a hole in the upper flange, beats me. I don't think you want pressure oil to spray up there.
Günther
Thread Starter
Melting Slicks
Joined: Mar 2004
Posts: 3,472
Likes: 18
From: Lake Ozark, MO
The first hole is located down about 1 inch under the distributor seat, it is a bout 3/16 diameter. The larger hole is located about an 1 1/2 inches above the drive gear and it is about 5/16 diameter.
Race Director
Joined: Nov 2000
Posts: 11,872
Likes: 12
From: Waterloo ontario Canada
The large lower hole is for mist lubrication only. From past experience and problems with lower bushings I drill a 1/16th hole in the housing between the two machined surfaces on the lower part of the housing. I also file a fine groove in the lower machined surface is such a way so that when the distributor is installed and timed this grove is above the cam gear. This groove allows pressurized oil to leak past this sealing surface and lube the cam/distributor gear. This groove is about .030 deep and .030 wide. Just enough to leak.
If you drill the 1/16th hole in the lower part of the distributor you need the larger hole to alow oil to escape.
I would definitely want some kind of hole in the lower part to lube this bushing
If you drill the 1/16th hole in the lower part of the distributor you need the larger hole to alow oil to escape.
I would definitely want some kind of hole in the lower part to lube this bushing
Race Director
Joined: Feb 1999
Posts: 19,659
Likes: 34
From: Lenoir City Tennessee
Ci 6, 8 & 10 Veteran
St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14-'15
Originally Posted by Hvymtlc5
Got em drilled. Waiting for the shim kit to arrive. 5 to 7 thousands is acceptable, right?
I finally ended up around .007 or so. Pretty fun job to do. Just remember to align the dimple in the cam gear with the rotor tip.
While in there, go ahead and check the limiting bushing for the advance plate. Mine was worn out and had to be replaced.
Race Director
Joined: Sep 2004
Posts: 11,874
Likes: 263
From: Arlington Va Current ride 04 vert, previous vettes: 69 vert, 77 resto mod
Lars shimmed mine so i dont know the clearnace but it made a difference in the quality of the idle and in performance. this a good thing to do
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