New Engine Knocking

[Terry Burtz, Calif]

If the oil pump or distributor drive gear bushing is not secured to the cylinder block, you might hear a knocking sound.

Oil pressure pushes down on the oil pump and up on the distributor drive gear bushing.

If the oil pressure is high, the unsecured oil pump or distributor drive gear bushing can move.

When the oil pump or drive gear bushing moves enough, the oil pressure is relieved, and the spring at the bottom of the oil pump or the spring in the valve chamber that holds the distributor drive bushing in place will return the oil pump or distributor drive gear bushing to their proper position, causing a knock.

Buddy Ogden has one of the new engines that knocks when the oil is cold, but the knock disappears as the oil warms up.

If Buddy is using an oil pump that cannot generate enough oil pressure when the oil is hot and thin, the oil pump and distributor drive gear bushing will not move, and there will be no knocking. When the oil cools, the pressure increases, and the knock comes back.

Please follow the "Builders Guide" and ensure the oil pump and distributor drive gear bushing are secured.

[Will N]

Terry, can this same thing occur with a standard Model A oil pump, or do they not put out enough pressure/flow to overcome the upward push from the coil spring at the base of the pump?

[Benson]

In 1976 I built a Model B with drilled crank and modified for full oil pressure using Model A pump.

Followed instructions in 1970, Hot Rod Magazine by Dan Iandola (sp).

Oil pump put out 110 lbs pressure which was enough to lift the 3/8th inch thick aluminum valve cover with cold oil. Pump was ported for more volume. This blew out the gasket at bottom of the cover.

The oil pump OR distributor drive bushing knocked with cold oil.

Ended up welding a V8 oil pump relief valve with modified spring to shaft of A pump.

That controlled the oil pressure to 35 lbs at 55 mph with hot oil.

Hot oil pressure was 2 to 5 lbs at idle.

Maybe there was not enough oil volume at idle and may be why Terry increased the oil volume of his new pump as noted in another post on the Internet.

[nkaminar]

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When I built my Burtz engine I was lucky to have a Stripe oil pump that bolted to the block (with some added threaded holes). I bought the Kliesen external oil filter housing with the external adjustable pressure relief valve. I am really happy with that setup. The pressure was very easy to adjust. I have it set at 25 psi and it maintains that pressure with hot or cold oil, idle or high rpm. Kliesen does not have a web site. His ads are in the back of the club magazines. 949-466-7475, [email protected].