The definitive oil filter study

[cp1969]

You missed my point...or more likely, I didn't explain it very well.

At any pressure above the bypass pressure, the valve opens--doesn't matter whether the filter's clogged or not. Say your oil pump generates 40 psi and the filter bypass is set at 20--a whole bunch of oil is NOT being filtered.

 

[Toolite]

If the by-pass valve has a psi rating of "20" it would open when there is a drop of 20 psi from the inlet to the outlet side of the filter,as a clogged filter would. The by-pass valve works on pressure difference, not system pressure.
Wayne

 

[cp1969]

Yeah, a guy at work explained it to me as well.

Duh, I don't know what I was thinking.

 

[bradheiter]

I'm not sure how this applies, you decide....I have worked as a mechanic and then as Service Manager at motorcycle dealers for over 40 years. I have always cut open the oil filters of my bikes at every oil change {never did it with my cars I just buy the OEM filter and used that} (it has saved me a bit of money as I can see what is in there (if I see things I am not expecting I figure out what it is before riding my bike again) before an actual failure). What I have seen in filter quality even from the same OEM part varies ALOT, it would seem that from their order to order quality changes (I mean to the number of pleats,how many there are, how thick the paper seems to be,the springs etc..) I assume not at the cost of warranty work? I don't use Fram motorcycle filters, not because they are 'made poorly' but because I have cut too many apart that are put together wrong. As in the spring on the wrong side of the check valve or there being no check valve for the spring to push on. Fram has a lot of factories, it seems some are better than others. I'm too new to tractor ownership to buy anything other than the OEM filter. It may not be better than another but if I have a problem they can't blame it on none OEM parts. My tractor cost 16,500 the OEM filters are only 11.00. I'm playing it safe till I learn more.
Brad

 

[cp1969]

The poor assembly quality may be related to the fact that, at least at one time, Fram was the most counterfeited filter out there. I saw a segment on 60 minutes(?) once about counterfeited items and Fram filters was one of the brands on it. Levi's jeans, too, IIRC.

 

[fractal]

</font><font color="blue" class="small">( I change oil and filter twice a year, once in spring and then again in the fall. The mileage between spring and fall is usually 2/3rds of the yearly total. When I drain the oil (Mobil 5-30W) it still looks good, so I strain it through fine mesh and reuse it in my power mowers, etc. )</font>

Not to change the subject from oil filters too much, but does this work ok for you? I have heard people say that the little 3-8 hp air cooled motors (b&s, honda ...) are harder on oil than your automobile and therefore need the best oil you can get. I started using mobil 1 in my air cooled motors a couple years ago. The stuff may cost 4 bucks a quart but a quart will do 2-3 engines.

My dad was a part time airplane mechanic and had a saying "buy the cheapest gas you can find and the most expensive oil", but that probably originated when price really was some indication of quality /forums/images/graemlins/smile.gif

 

[gsxr1100]

My wires brother owns a gas station and says the same thing. Also the smaller engines are harder on the oils, so yes. I think because the smaller engines are air cooled thus more stress etc.