cornbinder89 wrote:Steve, I didn't read the whole link, but a the 1st page and would say your way over thinking filteration. 1st point, bypass valve settings. A pump only produces flow, not pressure, restriction creates pressure.
I mostly agree, that's why I talk extensively about the different restrictions of the different filters on the 2nd page.
Unless your pump is totally knackered, it is capeable of exceeding 300 psi with enough restriction.
I respectfully have to totally disagree with you on that one. (I'm referring to the 304 SV V8 engine and similar engines). You can fill a filter with hardened concrete and you will never see more than about 60 psi (before the filter) regardless of the viscosity of the oil and rpm of the engine (within reason on both). There is a bypass in the oil pump (which some people shim to bring up to 60 - 70 psi) that will prevent the pump from ever producing more than that amount of pressure. And 10 to 30 psi would be more normal for a hot engine idling. Of course, with the filter filled with concrete, the oil pressure the engine sees would be zero.
Since all clearances (other then pump internal clearance) are beyond the filter, a plugged filter with a 30 PSI bypass will bypass any pressure above that, and since there is no place for the pressure to bleed off before the filter (depending on where the releif valve is located),
I have never rebuilt a IH 304 V8, but isn't the bypass part of the oil pump and before the filter? And, from what I understand, the oil pump will only produce no more than 30 psi on a used engine at idle speed when hot, regardless of after-filter restrictions.
it should have no problem opening the valve and lubeing the engine (as long as it bypass as well below relief setting). The pressure down stream from the filter (engine side) will remain about the same as before the filter plugged.
Definitely not true. And that's speaking from experience. I bought my first ever IH last December. It arrived a couple months later, while this site was crashed. One of my first posts on another forum was my concern over the very low oil pressure I saw on the gauge. The oil did not "appear" to be dirty. And because my engine has the very deep Loadstar oil pan, initially (after all, I was new to IH) I did not see any reason to change the oil. But based on responses I had to my post, the first thing I did was to change the filter. I went from the Carquest filter that was on the engine (made by Wix) to the Wix recommended 5 inch 51452 oil filter. My oil pressure, using the same old oil, same gauge, etc More Than Doubled - both cold and hot readings, and both at idle and at higher driving speed. That big overall pressure reading improvement can only be attributed to the filter, as nothing else was changed. That started me on my quest to find the best filter with the best technical specs (which definitely is not Wix, as shown on page 2 of that post. There are other equivalent filters that filter contaminants 4 times smaller and with less, much less restriction and have a much greater contaminant holding ability). To continue with my story, shortly thereafter I changed the oil and replaced the Wix 51452 with a Wix 7 inch 51459 oil filter. I again noticed a slightly higher overall pressure reading than with the new 51452 filter. But I cannot say if that was entirely the fault of using a larger filter, as I also had new oil.
Too low a bypass setting will pass dirty oil on cold starts, too high may starve the engine if the pump is worn,
And its my contention that 30 psi is too high a setting for the oil filter bypass valve. The IH spec is for 8 psi.
but should show on any pressure indicating device (light or guage). Before jumping filter numbers, cause some "stat looks better then the orignal called for, remember, flow or capacity in gal/min is more inportant then just about any other 'stat, and this is rarely included in the books.
I agree, flow in gal/min based on applied pressure is the second most important spec a filter has. (I'm referring to filters here, not oil pumps. For the most important spec, although its pretty obvious, you'll have to read page 2 of my post). And no manufacturer lists that information willingly. However, I was able to obtain that info from one manufacturer and after seeing and comparing that info among their various filters, and crossing with Wix equivalent filters, I will never go back to Wix.
2nd, I used to be in the 3000/ 3 month camp for oil changes, but today that isn't needed. I change about once a year, and my engines last longer then the chassies they are in. Both oil and bearing material has inproved.
SV's had a rep for flakeing cam bearing, and no amount of oil changes or filters will stop or correct that.
Well, I'm not sure about that, based on my internet research (not real-life experience). From what I've been able to gather, its the combination of low oil pressure from poor filters and lack of oil changes, and more especially from the acidity buildup in the oil from infrequent oil changes eating away between the bearing layers that cause the cam bearing degradation and flaking. Many people do not use their IH vehicles on a regular basis and I've seen posts where people have stated they go 3 or 4 years
between oil changes because the oil does not look dirty.
If your worried then pull the cam and install modern bearings from a reputable supplier.
One last note,
It is becomeing harder to legal and respocably dispose of spin-on filters by the DIY'er. In most areas they need to be crushed and all oil recovered before going into the trash. There are services that will collect and do this, but are byond the means of most DIY's.
Well here in Los Angeles you just take your old oil filter and used oil to the local auto parts store. They collect that. It could not be easier. They've done that for years here. Don't all auto parts stores do that now?
Cartridge filters can most times be burned,
You try that in your back yard here in Los Angeles and you will quickly find the police and fire department quickly knocking on your door and issuing you some very expensive tickets in the hundreds of dollars. I don't know if auto parts stores will take partially burned filters.
and any metal recovered after the fact, makeing disposing easyer for DIY's. Some service stations will take used filters for proper disposal, but many will not. Check local laws before disposing of spin-on's.
Tue Jun 04, 2013 9:30 pm 
I am sure this has been asked many times before and listed elsewhere but I cannot find it here.
