Re: 359 Noisy Lifters
Posted by HH56 On 2023/7/2 10:53:36
I would recommend looking thru the service bulletins as there are a few mentioning causes and corrections for noisy tappets. You can select the service index on the left and then choose 51-4 and engines to find them. You didn't mention how long the engine was running in total but some have reported it took a fair amount of time to get all the air out of a freshly rebuilt engine before their lifters quietened
If it ran a decent amount of time and still noisy, I would also check the lifter supply pressure as per one of the bulletins. A restriction in the pigtail tube or one of the fittings could be lowering the pressure.
You did mention changing the front plug. The orifice for hydraulic lifter cars has a specific opening Packard wanted so if larger, that could be bleeding off too much pressure. IIRC, a bulletin on another subject casually mentioned another function of the orifice was to provide a more rapid bleed out of air which might get trapped in the lifter gallery. If there is no opening it is possible any air bubbles in the oil could be collecting and affecting the lifter supply.
Attach file:
plug.jpg (163.90 KB)
If it ran a decent amount of time and still noisy, I would also check the lifter supply pressure as per one of the bulletins. A restriction in the pigtail tube or one of the fittings could be lowering the pressure.
You did mention changing the front plug. The orifice for hydraulic lifter cars has a specific opening Packard wanted so if larger, that could be bleeding off too much pressure. IIRC, a bulletin on another subject casually mentioned another function of the orifice was to provide a more rapid bleed out of air which might get trapped in the lifter gallery. If there is no opening it is possible any air bubbles in the oil could be collecting and affecting the lifter supply.
Attach file:
plug.jpg (163.90 KB)
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