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Any suggestions on bypassing the oil filter on a 41 super eight engine. I feel that this oil filter is very inadequate and creates a mess when changing the oil and can be a source for leaks. I change the. Oil on my 37 and 41 Packards around 500 to 700 miles.

How depends on your present configuration. Can't speak to the 37 but when the 356 was introduced for the 40s all the oil supply for the hydraulic lifters passed thru the filter. Because of dirty or clogged filters noisy lifters started to become more common. After switching to a different type filter element that apparently was not the cureall, in the June 15, 1941 service counselor instructions were given on how to increase oil flow to the lifters by converting the full flow filter to the bypass type filter. That entailed adding a pigtail to directly feed oil to the lifter gallery and drilling and tapping a hole into the crankcase so oil could then drain back from a now partial flow filter.

If your car has a tube coming off a tee on the bottom port on the drivers side to the filter and then another tube from the filter to the upper port it is still the original full flow configuration. To eliminate the filter you would have to disconnect the filter and add a pigtail between the tee where the filter got its feed and the upper port. That will totally eliminate the filter.

If your car already has the small pigtail between the two ports then it is just a matter of disconnecting the filter feed and plugging its port -- either by removing the second tee if the field mod was done or changing out the later 4 way connector to a tee (or finding an inverted flare plug to eliminate the extra port on the 4 way) if the car has that arrangement. You would then remove the other tube draining into the crankcase and plug that port.

If you remove the second tee or the 4 way connector there may be one port with a smaller opening or orifice. If so, that is the feed port for the partial flow filter. The lifters were fed from the full flow opening. Save them or be careful not to use them for something else that might not like the orifice.

I guess with the frequent oil changes the filter is not really necessary but even though it was optional, Packard did automatically provide it or recommend installation as part of the option for engines getting hydraulic lifters.

Any oil filter is better than no oil filter. The partial flow or bypass filter is surprisingly efficient. It does a finer job of filtering out small dirt particles than the modern full flow filter. It takes from 10 minutes to half an hour for all the oil to go through.

It can be messy changing the filters. It helps to wear rubber gloves and have a container lined with a plastic bag. Pull the filter out and drop it in the container. Wipe the filter cannister with rags or waste. Pop in a new filter. This only needs to be done every 5000 miles.

Some filters have a drain plug in the bottom.

Your filter does an important job of keeping the oil clean and preventing wear. You would be better off to keep the filter and extend oil change intervals to 2500 miles.

Concerning the mess inherent in changing by-pass filter elements, I use a turkey baster to extract as much oil as possible from the filter housing into a close at hand container. Then lift the element out and into a similar container right next to the filter housing. A little time consuming and awkward but....it gets the job done with a minimum of mess.

The bypass filter is extremely effective at removal of fine particulates which would be harmful in general and specifically to your hydraulic lifters. With the techniques others have mentioned it doesn't have to be a messy job to change, and with the mileage most of us put on an old car, you'd only be changing it once every 3 or 4 years.

I purchased a siphon pump at Harbor Freight Tools. It is orange in color ,cylindrical in shape and does a great job of siphoning the oil out of the canister. A couple of my antique car friends suggested bypassing the filter but I guess I'll leave mine intact. I just was under the impression that they were not very effective thus my reason to bypass. Thank you to all of you that have commented on this forum.

This discussion on the AACA web site about the effectiveness of bypass filters is is particularly interesting.

forums.aaca.org/topic/240928-by-pass-oil-filters-how-effective/#comment-1268052

The effective practice I used with changing the bypass filter was torqing the cover to 15-18 lbs ft torque. Over tightening the cover will distort the gasket and cause a leak.

Packard motors with the floating pickup avoided large particulates that will settle overnight and a key aspect of the system is periodic oil pan cleaning. The manual specifies an 8000 mile filter change interval and for a car that sits in the garage a lot that is essentially a lifetime filter.

So I would pay more attention to maintaining a good air filter and keeping the oil fill mesh wetted.

As well, recently I was a addressing a valve sticking question and I would use a multigrade oil in those motors to avoid oil starvation of the valve guides unless the motor has an oil pressure problem due to wear.

Packard engineers were among the best in the business, they had extensive labs and a world class test track. Proof of their expertise is in the service letters which have few major alterations suggested. Before I'd make a change in the oil system, the most important one in the engine, I'd check to see how other major car companies of the era designed their engines and how later (improved) engines were designed.

Today all cars have oil filters, that should answer your question