GM Block Mounted Bypass

The jug is a standard 1 gallon plastic milk jug, I had 22oz. of water in it. The pencil is 1". I started with 128oz (8lb), way too heavy, poured out 64oz, still too heavy, got down to 16oz, then went up from there. Each time I used a cooking measuring cup. Here's a pic of the milk jug, I can't see it being more than 2oz though:
1 volumetric oz of water is 1.043 oz of weight, so 22 oz of water in the jug would weigh 22 x 1.043 = 22.92 oz . If you added say 3 oz for the jug and pencil together, then it would be 26 oz total = 1.625 lbs.

That would give P=F/A =1.625/0.15 = 10.8 PSI. That sounds a lot like the stock OEM bypass valve setting. I wonder if the new one you got is really set to the stock PSI opening?

But once the valve is open, the entire plate is exposed to oil pressure, wouldn't that larger area count after it opens?
No, it's like a bypass valve built into an oil filter. It takes a certain PSI on the valve face to crack open the valve. That's how this one in the filter mount also works.
 
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Yes blue is fine (make sure all the treads are clean and dry, both the bolts and the block, your brake clean sounds good, let it dry). 18 ish ftlbs for torque (it is a fairly thin bolt). This piece is static there is nothing to work the bolts loose. As well, the filter adds tension to the bolts when spun on. You can go orange or up to red but next time you need to remove the adapter (engine overhaul etc.) it will be a struggle, not impossible, but a struggle. It is not wrong to use the orange or red if you want piece of mind, I just use blue on this component.
OK, I used blue, got the bolts snug, then just a tad more, I don't think I put more than 5 ft lbs on it. Hope the blue holds. Its says it sets up in 10 min, takes 24 hours to cure, I'll give it 12 hrs before putting the filter back on.


Thought I'd never get all that 54 year old gasket off, old school razor blade works the best! The adapter & bolts had overspray on them, it's been through at least one rebuild. Pistons have "20" stamped on them.

Clean Adapter Mount.webp


Here's the finished product:

New Adapter Installed.webp


I am also curious what was the cost from GM that you paid on it if you don't mind letting me know? I see everything from $65 to $85 online just wondering what the cost is to a regular guy like me.

The link that @ZeeOSix posted above is where I got it, $68.99. Bolts were only $4.99 ea, so I splurged on them, lol.
 
Searching the p/n stamped on your filter mount came up with this. 10 to 11 PSI is what we are calculating. But the package it came in (post 32) has p/n19299222, which Summit Racing says should have a 17-18 PSI bypass valve. Seems like conflicting info and part numbers, but the search result below matches what we're calculating.

1762148047994.webp
 
Searching the p/n stamped on your filter mount came up with this. 10 to 11 PSI is what we are calculating. But the package it came in (post 32) has p/n19299222, which Summit Racing says should have a 17-18 PSI bypass valve. Seems like conflicting info and part numbers, but the search result below matches what we're calculating.

View attachment 308355
Ya it's the same part number on the OEM item, too, just in a different place on the flange. The Melling has a different stamping, 305-350. Some have only 350 stamped.

The Summit Part #SUM-120115 for $16.99 has 305-350 stamped & they say it's 15-17psi. Summit Part #SES-3-60-08-900 for $39.99 has the same stamping, includes 2 bolts & they say 14-17psi. Melling #MFA350 for $19.99 has the same stamping, & Melling Tech Support says 9-11psi.

Amazon has the Melling item for $20.97 free shipping, no specs but first line says "Made in China".
They also have a "Kipa" brand with stamping OFA350 for $18.99 with 2 hex head bolts, no gasket. Description says do not use a gasket, as it can be sucked in, & destroy the engine, etc.
Another Amazon item is "GM Genuine Parts" number 19299222 for $83.72 but one week shipping time, same part as I got w/gasket, no bolts.
Amazon has a plethora of no-name items around the $15-$18 range. The reviews I saw said they were purchased mostly to eliminate leaky oil cooler lines, but some guys with later model engines said this didn't fit. This probably explains why they are so abundant & readily available.

Conclusion: The GM item seems to be the most reliable, we don't know the QC of those made in China knock-offs, things could fail & get sucked in, that would be all bad. The new one I got showed a higher psi compared to the OEM one I had so that's a plus, maybe not the 17-18psi advertised by Summit, but an improvement.


 
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That would give P=F/A =1.625/0.15 = 10.8 PSI. That sounds a lot like the stock OEM bypass valve setting. I wonder if the new one you got is really set to the stock PSI opening?
I think you're right. The answer from the "Summit Racing Expert" is 7 years old, we don't know how that answer was reached. I just looked again at the description, the pictures they show are not of the same part, the valve face is a different color, no marker tags either. My part had a marker tag on the pressed-on spring retainer underneath.
 
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OK, I used blue, got the bolts snug, then just a tad more, I don't think I put more than 5 ft lbs on it. Hope the blue holds. Its says it sets up in 10 min, takes 24 hours to cure, I'll give it 12 hrs before putting the filter back on.
I didn't need the truck today, so it will get over the specified 24hr cure time.
 
1 volumetric oz of water is 1.043 oz of weight, so 22 oz of water in the jug would weigh 22 x 1.043 = 22.92 oz . If you added say 3 oz for the jug and pencil together, then it would be 26 oz total = 1.625 lbs.

That would give P=F/A =1.625/0.15 = 10.8 PSI. That sounds a lot like the stock OEM bypass valve setting. I wonder if the new one you got is really set to the stock PSI opening?


No, it's like a bypass valve built into an oil filter. It takes a certain PSI on the valve face to crack open the valve. That's how this one in the filter mount also works.
I had crushed the jug for recycling, but kept it because not knowing the weight bugged me. I got a scale, the empty jug weight was along the lines I was thinking. I went a step further & filled it with the same amount of water I used for the test & got some surprising results.

The empty jug & pencil:
Empty Jug.webp


Jug with 20oz water:
20oz Water.webp


Jug with 22oz. water:
22oz Water.webp


Jug with 24oz. water:
24oz Water.webp


20oz. (21.761) opened the old one but not the new one, 22oz (23.468) opened the new one.

I used 8oz measuring cup to fill for this test, so 3 separate fills for the first measurement, then adding 2oz for each subsequent measurement could account for the discrepancy. The 2oz. increase is consistently 0.85oz per fluid oz., but the first 20oz fill comes out to 0.96oz per fluid oz.
 
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^^^
1 volumetric oz of water at room temperature is 1.043 oz of weight, so your measuring cup(s) are off a bit. What matters in the end is the actual weight (force) pushing down on the face of the bypass valve, which the measurement of the jug plus water and pencil on the scale is giving, and the scale is no doubt pretty accurate.
 
^^^
1 volumetric oz of water at room temperature is 1.043 oz of weight, so your measuring cup(s) are off a bit. What matters in the end is the actual weight (force) pushing down on the face of the bypass valve, which the measurement of the jug plus water and pencil on the scale is giving, and the scale is no doubt pretty accurate.
So using your formula with the corrected weights, the OEM item opened at 9.1psi, the new one opened at 9.8psi, both were fully open at 10.5psi. I eyeballed those measurements very closely, but the capillary action of the water on the glass measuring cup could have caused me to use less than I thought.

The lower pressure differential setting may be beneficial due to the fact that higher deltaP can dislodge already captured particles in the media as you have noted in the past.

The margin for error is considerable, the second picture with the 20oz works out to .964oz per fluid oz, & the third & fourth pics work out to about .85oz per fl. oz. The first 20oz was using a 2 quart measuring cup, the last two were each with 2oz added from a 1 pint cup. In the original test I filled the jug with the 2 quart cup, then subtracted with the 1 pint cup, so I could have been removing less than I thought, making the original weights a little higher. Given that, I would conclude the figure you quoted in post #43 of approx. 11psi is correct.
 
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