Oil Filter Bypass Valve Flashlight Test

Here are the pictures of the bypass leaf spring. You can see near the edge corners near the hat draw has some wrinkled edges/flange.

Top left is the Fram Titanium 3600 which has a fiber seal it mates to. Bottom left is from a FD3600. Top right came from a MP9688 and the bottom right is from a FE7317. I can feel the ridges on the winkles...

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I think the only spin-on filter with metal end caps that had a fiber sealing ring for the leaf spring was the OG Ultra & OG Titanium. I don't recall any other brand or model using such a design.

One advantage of filters with fiber end caps is that they will seal better than a metal-on-metal seal on the end caps.
Yes, the PF63E has a snug fit with the fiber caps …
And with 20 psi+ you can see the springs got bigger so they could potentially seal better closed …
 
Fwiw,I don't have an issue with metal on metal seal area per se. Wix/Napa Gold has long used it with their base end bypass piece. But there the milling of mating surfaces is fine and a relatively wide area. Then, combine that with use a coil compression spring. I you've ever done c&p Wix/Napa gold with coil spring filter, you know those about pop out of can when cut open. Iirc, WCW did a vid showing what a coil spring does when can cut open. I'm confident the force there maintained the seal.

Otoh, the flat/stamped spring type provide just enough force to hold the element with adbv in place. Imo, it's more difficult to maintain the seal with the separate stamped spring and bypass combo piece. That said, not 100% sure of the mechanism for the light seen, but have a fair idea. I'll know more when I c&p the FE7317. Maybe I won't find any seal area light, and that too will be fine with me. My.02
 
If only someone would invent a filter mount that has a bypass valve mounted in the block. Then the filter could be just a paper cartridge, with 100% of the oil going through the filter when the bypass is closed.

Nah, that will never happen, will it?

As far as this video?

You can’t tell anything from the light except that the seal is not “perfect”. How much oil goes around the case, through that gap? It’s not accurately measured by the flashlight.

This might be important, or it might be much ado about nothing.
Excellent post and as a throwback does anyone remember the OF as a screen door or dire emergency device vs some magic wear protector discussions, ca 2004 or way back?
 
Fwiw,I don't have an issue with metal on metal seal area per se. Wix/Napa Gold has long used it with their base end bypass piece. But there the milling of mating surfaces is fine and a relatively wide area.
When Wix/NAPA Gold went to a dome end bypass valve they still used a metal spacer where the base end bypass valve use to be. That spacer can be seen in the WCW video (starts at point in video). The sealing between the spacer and the end cap is just a thin raised ridge similar to discussed above. Probably good enough, if those parts are flat enough and there's good spring pressure compressing the guts tight.

 
..... Probably good enough, if those parts are flat enough and there's good spring pressure compressing the guts tight.
With the use of the coil compression shown in vid at 3:33 on the XP/Platinum, no light test, I'd feel pretty good about the seal being maintained. Otoh, I might be less confident of that with the use of stamped flat spring.

As an aside. XP/Plat always used dome bypass and some with a spacer, I'd say just standardize element size to equivalent Wix/Napa Gold filters. And some lower tier Wix like Napa Silver also used dome with spacer. It's also why they used that odd looking combo valve on lower/lowest, same size as base end bypass piece. Some said that did leak at the seal, but IDK. Wouldn't want to use a combo valve filter anyway.
 
Not sure the poppet in an oil filter provides the same functionality as a pump relief valve …
Two separate functions. The bypass valve in the filter operates on the dP across the filter media. The pump pressure relief ("bypass") operates on the output pressure of the oil pump. A filter could go into bypass before the pump hits pressure relief, or the pump could hit pressure relief before the filter bypasses. It all depends on the settings of each and the operating conditions.
 
Two separate functions. The bypass valve in the filter operates on the dP across the filter media. The pump pressure relief ("bypass") operates on the output pressure of the oil pump. A filter could go into bypass before the pump hits pressure relief, or the pump could hit pressure relief before the filter bypasses. It all depends on the settings of each and the operating conditions.
I know …
 
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The video was interesting and shows perhaps how not not to make a filter bypass section. Its not rocket science but the mass production of these is part of the problem. Lets say a filter is rated at a certain micron level (say 5) that's small. IF... The gap I see with the light is larger than 5 ( and I think almost everyone would agree it way larger than that) than there is a good possibility something will pass through the gap. IF what we see is represented correctly, and there isn't any clear sealant that the light can pass through between the filter case and what we see is a gap here, the spring bracket/ valve / design is a problem for me. 254 microns is 10 thousandth of an inch. What size gap do you estimate we see. Even if its 1 thousandth that's a 25.4 micron continuous leak. This posting tells me to stay away from these brands altogether. I would be interested in a comparison between other oil filter brands and their weak points.

There are some YouTube vids on filters. Not sure how much attention was put on the bypass valve.
 
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