Bypass filter install

I've been meaning to post the details for the bypass filter setup I installed on our Prius.
But alas, I haven't found the time to finish the install writeup.

So rather than continue to delay I thought I might share a few photos.
Maybe that will help motivate me.

Enjoy...

I too would like 'do you want to know more' (starship troopers quote) hehe

As I understand it, the Amsoil filter in the photo is an ultra filter(is that right prefix?), it can filter out something like 1 micron particles. The oil pump can't generate the pressure to move oil at the necessary rate through such a fine filter. So some of the oil goes through this filter and the rest through the regular filter.

It gets the oil really clean.
In theroy, with a synthetic oil, you can go a year plus between changes.

Someone here set up one outside the vehicle, instead installing a filter on each one. He runs the used oil through, gets it analyzed, and generally is able to reuse the oil again.

Here's that thread:
http://priuschat.com/index.php?showtopic=2...l=bypass+filter

I just change the oil and filter every 4K miles and use Toyota oil filters. If I were planning to keep the car for 1M miles maybe I would consider that.

Regardless of if something like this works, I'm a BIG fan of modifications for the sake of modifying (if that weren't yet abvious). That Mike accomplished this in such a tidy package impresses the hell out of me. If it works as advertised, that's just icing.

I like the concept of having two filters to increase the amount of filtration. This seems to be a parallel setup, and the only reason I could see for doing that would be to increase the rate of flow. Is there a benefit in increasing the rate of oil flow in the Prius?

Can this device be configured (or modified) to allow us to run two filters in-line (in series) to increase the amount of filtration? If so, what does that do to the rate of flow?

This level of filtration would be great in a car that only has a gas engine. But for this car, the displacement of the engine is so small, it doesn't need a high flow oil filter. As for how long the oil will last... deposits in the oil are only a small part of it. It is when the oil chemically breaks down that it is no longer useful. I have been using the 15000 mile mobile one oils for about 2 years, and never had a problem with it on a Nissan Frontier. I plan to continue using it on the Prius, and will change it every 15000 miles. Oil will break down over time too, regardless of mileage, so 6 months should be the longest no matter how far you drive.

Apparently this thing works pretty well. Plenty of guys (inlcuding me) on a Ford Explorer forum used Amsoil in their trucks, and quite a few used the bypass setup. I would check my oil frequently, but my oil was good for at least a year of dirty driving.

Amsoil is great oil and I still use it. It's good for 25,000 miles between oil changes, as long as you change the filter every 5,000. I never tried that, but I did use it for about 12,000 miles. It looked like it came straight out of hte bottle when I drained it too. Pretty good stuff. They also make an engine flush that you use before you do an oil change, and that stuff really did flush out all kinds of crap.

I was kinda skeptical about the whole "independent deler" thing with Amsoil, but I never had any problems. Guess it sounded too much like Amway...

Anyhow, it's good stuff.

I thought with a dual filter setup that the first filter would filter the oil and then send it to the second filter to filter the oil, with each one being able to be bypassed under high pressure conditions. And that would also seem to be the way to keep the ultra fine Amsoil filter the cleanest for the longest too. Is it also possible to use that expensive Amsoil filter longer then too, if you maybe dump out the oil in the filter when you're changing oil?

I am also wondering if the Amsoil filter claims it can filter out 1 micron particles. That is getting almost too small to be filterable. And I also agree that something as small as 1 micron won't hurt the engine, but it is just the great feeling if you can really get the oil that clean.

Wow! This thread is just chock full of testosterone! :blink:
[ducking and running]

No full flow oil filter, even K&N or Mobile 1 filters, which test better than the Amsoil full flow filter, can filter out particles that do cause wear, because such fine filtration would cause a restriction to oil flow. So, the principle of the bypass is that the oil goes through the full flow filter as the manufacturer designed, it is literally in series with the oil pump. However,the bypass filter oil lines bypass the full flow filter, thus not causing any restriction. Enough oil does flow thru the bypass to have all of the oil go through the bypass filter in less than a minute. Since the bypass filter filters down to less than 5 microns, it filters out any particle of size large enough to be able to cause any wear.
It is of particular advantage in dusty areas and when the change interval is long. Since the bypass filters so well, the filters do not have to be changed until the oil is changed, though I do change the full flow only at about 8000 miles, changing extended Mobile 1 and the Amsoil bypass at about 12-15000 every summer on a nice day.
dave

Back in the 70s there was a super fine oil filter which was marketed that by using this filter you never had to change your oil. This filter was so fine all you need to do is change the bypass and genuine filter every 5000 miles and top up the oil. You never need to drain the oil.
This was a true bypass filter. It tapped into the oil gallery at a gallery plug after the main genuine filter where a small metered flow of oil was diverted from lube duty to pass through this super fine filter. The filter would remove super fine crap from the oil then return it to the sump via a return line into the rocker cover. Only about 1% of the oil went through the filter but the oil pump moves a lot of oil each minute so by allowing 1% through the bypass filter all the oil eventually went through the bypass filter.(3.5 litres travels around the engine 1000 times, on average all the oil has been through the bypass filter 10 times.)

The filter element was very cheap, it could then and still can be purchased in packs of 2 up to 16 in the super market -
Toilet paper!
The filter housing was designed to support a roll of cheap 2 ply toilet paper, the oil was forced through the paper(centre cardboard tube was blocked by a spool through the centre) from end to end. The paper once it has oil in it swells up to fill the housing and the oil passing through the paper from end to end had all the crap wiped off of it and it went back to the sump.

Changing the toilet roll and the conventional filter meant about 1 litre of oil was added every 5000 miles instead of 3.5 to 5 litres depending on the engine size. This was in the days when an oil filter was about the size of a toilet roll.

Believe it or not!!!

Nulon believe they work at removing impurities. They specify the bypass filter be disabled during treatment.

from http://www.nulon.com.au/applications.php

Does the Amsoil bypass filter have a return line to the sump? That is the only way I can see it gets the oil through the restrictive bypass filter.

After I rebuilt my Morgan 4/4 with a overbore and long stroke steel crank from 1600 cc to 1840 cc. I changed to Amsoil and fitted a bypass. I sampled the oil every 6 months and changed the oil the only if the lab report said it was needed.

The bypass system only makes sense if it is part of a program.

Synthetic oil has quality of the oil built into the molecule and uses little if any viscosity improving additive, the oil does not suffer from additive depletion which is the major cause of oil loss of performance.

Molecule shear is also a factor in oil degrading and synthetics are more resistant to this then conventional oils.

The bypass set up I had took a feed from the oil pressure gauge tapping and returned to the sump. This has the effect of draining off oil, and topping up with clean fresh oil. the filter has a large area and a slow flow through a very fine material, this type of filter works better he longer it is in service. As it becomes partially clogged it filters finer.

The changing of the element should be carried out when the pressure drop across the filter becomes too high, if you don’t have a delta P gauge a rough check would be to feel the bypass filter and the full flow filter when the engine is hot and if the bypass is noticeably cooler then the filter should be changed.

The oil never failed test on anything but fuel dilution (I was running twin Weber DCOE40’s) and that only happened if the sample was taken after a period of short runs, if it was sampled after a long high speed run then the fuel dilution was negligible, high speed running can evaporate fuel from the oil.

If you fit a bypass and change oils at the maker recommended change time, then you are not getting the best use from the system. It is ideal for extended oil changes but needs backing with samples and analyzes.

My Morgan is off the road now but I hope to get it going this summer and the part that wont need work will be the engine.

Jon the Chief

I just found the Amsoil website today, and I am seriously thinking about getting one of these. I thought I would take an additional stab at describing how it works. Yes, it is true that the oil, similar to electrical current, will take the path of least resistance but not all of it. Say you stab your garden hose with an ice pick. Water will come out, even though the easier path is straight through the hose.

In electric circuits, if you put a 10K resistor in parallel with a 1K resistor, some current will flow through the 10K resistor, even though the 1K resistor presents the path of least resistance. The current of electricity (or oil) will be inversly proportional to the resistance.

So with the two filter system, the filters are in parallel, not series. Lets say 90 percent of the oil passes through the traditional full flow oil filter that can typically filter down to 20 microns. But studies have shown that the majority of engine wear is caused by particles in the 5-20 mircon range.

At the same time, 10 percent of the oil will flow though the 1 micron bypass filter. What this means is that any particles between 1-20 microns on average would travel around the system 5 times before it passes through and get trapped by the one micron filter. According to Amsoil, all of the oil will have passed through the 1 micron filter about every ten minutes.

If you drive 3000 miles between oil changes at an average of say 30 MPH, that is 100 hours on the engine or 6000 one minute oil circulation cycles.

So the question comes down to this. Do you want each 5-20 micron particle (The size that they say causes the most engine wear) to cycle through your engine an average of 5 times or 3000 times between each oil change?

On the other hand, with regular oil changes, the engine will go for 250,000 miles. The main reason I can see for doing this would be to keep the engine "running like new" a lot longer.

There are forums where all they talk about is oil. Yes these bypass filters do work. It makes perfect sense to have the fine particles filters in a "bypass" oil stream. It is also true that having a bypass filter will reduce the wear on your engine. It will also allow you to increase your oil change interval dramatically. It is all good stuff.

BUT. IMHO, todays engines, coupled with todays excellent engine oil, produce very, very little wear on an engine anyway. With reasonable oil changes, todays engines will go 200k miles easily. When you tear down a properly maintained 200k engine, one can usually see the original hone marks on the cylinder walls. So, why go through the trouble of a bypass filter system? Of course, it is a personal choice. And I agree they do work, but by the time my car hits 200k miles, I am pretty sick of it anyway.

A bypass filter makes more sense for a vehicle with a large oil capacity and the desire to run extended oil change intervals.(e.g. a heavy diesel engine and synthetic oil). Then you actually save money by buying less oil.

I'm not sure that it would be cost effective for the Prius with a 3.5 qt capacity, but it would allow you to use less oil, so maybe some would be interested for that reason.