Re: 1951 300 ticking noise

Posted by HH56 On 2022/11/3 12:20:43

JWL brings up a good point. Hydraulic lifters were standard on the 51 250, 300 and 400 models but was optional on the 200 and 200 Deluxe. If the engine in your car is original the motor number should start J4xxxxx and would have hydraulic lifters.

Dirt is an enemy of hydraulic lifters and the way the 51 and later postwar Packard engine is plumbed the filter was an option that usually was on hydraulic lifter engines (but not always). It is a bypass type with only about 10 percent of the oil from the pump going thru the filter and then is dumped into the pan. 90 percent of oil from the pump is circulated thru the engine and the lifters do not see any freshly filtered oil. If the oil goes a long time between changes or lots of sludge has formed any crud in the pan can be sucked up thru the screen mesh in the pickup and sent to the lifters. It could be that just sitting for a long period has allowed stuff to settle at the bottom of a lifter body where the ball valve is located and it cannot seal. Perhaps an oil change and time will solve the issue but if not then disassembly and cleaning may be the only option.

If by chance the engine has been changed and it has solid lifters then an adjustment could be all that is needed. The 51 200 solid lifter motor number will start J2xxxxx and any other year motor number will start with a different letter. The 200 or lower end models in other years also had solid lifters with hydraulics optional from somewhere in the 23rd series onward. Engines that had solid lifters as standard generally have a 2 or 3 as the second digit in the motor number.

If optional hydraulic lifters were installed at the factory there will usually be an H stamped at one end of the motor number -- usually as a suffix -- but we have found that H stamp is not reliably in the same place or even on all cars with the option installed. It could be they forgot but more likely it could have had hydraulics installed after it left the factory.