don't confuse the two clearance issues there should be less than .010-.015 up/down shaft travel between the distributor gear and distributor housing, once the distributors clamped in place on the intake manifold when shimmed correctly
Rule of thumb is
0.010" to 0.015". movement between the distributor gear and lower housing, thats not the same as the clearance between the oil pump drive shaft and the oil pump, the oil pump drive shaft should have about .050 up & down clearance with the distributor seated on the intake manifold, That stated you should be looking at the distributor housing wear area and place steel washer shims top, bottom or both to keep the gear as centered to the cam gear as possible. The bottom of the distributor housing wears during deceleration and the top while cruising.
if you seat the distributor and there's zero clearance so the distributor drive shaft has zero up & down clearance with the distributor clamped on the intake manifold, you need a distributor housing gasket or gasket and shim under the housing to intake clamping area this will prevent wear and excessive stress on the pump, you want .050 between the distributor drive shaft and the pump drive with the distributor seated and clamped.
big2bird posted some of this , on a different thread but it needs to be here also, and I ADDED STUFF YOU NEED TO KNOW For those of you who have one, factory or otherwise, and you have noticed your timing jumps around instead of steady, here is your problem. As you accelerate/decelerate, the...
garage.grumpysperformance.com
All,
I think I “newbie’d” my new oil pump. Any advice would be greatly appreciated.
…even if it’s “replace that new pump and do better next time”.
Melling 10553ST
1969 L46 SBC - unmodified / stock
Oil pan & gasket getting replaced
Figured I do the oil pump after reading the thread at:
garage.grumpysperformance.com/index.php?threads/installing-an-oil-pump-pick-up-tube.1800/#post-43110
First time changing pressure springs and I was using available tools.
Drove out old roll pin w/ punch & hammer, as carefully as possible. Had some heavy cardboard under it to minimize any marring.
Removed...
distributor gasket shims go between the distributor housing and intake manifold
Free Shipping - Moroso Distributor Shim Kits with qualifying orders of $109. Shop Distributor Replacement Parts at Summit Racing.
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distributor shims go between the distributor gear and distributor housing around the main 1/2" diameter distributor main shaft
Free Shipping - Moroso Distributor Shim Kits with qualifying orders of $109. Shop Distributor Replacement Parts at Summit Racing.
www.summitracing.com
maybe this will help
Free Shipping - Moroso Distributor Shim Kits with qualifying orders of $109. Shop Distributor Replacement Parts at Summit Racing.
www.summitracing.com
these shims go between the distributor seat flange and intake manifold to help keep the oil pump drive shaft clearance correct
to prevent binding on that drive shaft to the distributor gear.
Free Shipping - Moroso Distributor Shim Kits with qualifying orders of $109. Shop Distributor Replacement Parts at Summit Racing.
www.summitracing.com
these shims go between the lower distributor body and the distributor to cam drive gear.
https://garage.grumpysperformance.c...istributor-to-the-oil-pump.18145/#post-118056
you also need to get the oil pump drive shaft length correct ,to get the clearance between the seated distributor and the distributor,
to cam drive gear clearance correct