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Old 09-01-2016, 04:54 AM   #81
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"Perhaps we'd be fine w only by-pass??"

My 6-71 is a 1950ish version that spent almost 50 years in a can as a war stores item.

It only has a bypass "color filter" .The oil remains very clean for about 50 hours and is only golden by change time.

This is unlike my 8V71 or now Series 50 DD or Cat 3208 which is black all the time and black in 3 min of operation after an oil change.

The black stuff is too fine for a "modern " full flow filter to catch.

A real bypass filter added to the system would be a big help,

BUT many of my oil changes are on time , not operation hours , so the saving would be in engine wear.

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Old 09-01-2016, 01:21 PM   #82
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Originally Posted by Nomad Willy View Post

kchace Wrote;
"the drain back valves on any filter I have ever seen are only on the "input" side of the filter, not on the center outlet."
From that can I conclude that a horizontal filter should drain only part way if it had a drain back valve? That could be the case w mine.
Where are these drain valves located and can one see the valve and know if the filter has or does not have the drain back valve.

kchace also wrote;
"If the filter is higher than the engine (which mine are) it can always drain "forward" through the filter media and the center hole and into the oil galleries. This is probably not the best, maybe they drain down every time I shut the engines off?"
This I would like to know as if the oil drains back into the crankcase on shutdown every time one started up the filter would need to fill (and galleries ect) before oil pressure was realized at the engine bearings. It would be a strong indication that engine designers know that the lack of oil pressure during this time causes no harm or extra wear. That would confirm (perhaps) that the notion of serious engine wear at startup is serious business and promote pre-lubers. I've always thought if this was a problem pre-lubers would be standard equipment. Filters draining indicates that the notion of serious bearing wear occurring at startup is an "old wife's tale" and not valid.
Oil direction in a spin-on filter is always "into" the filter through the holes around the center hole, and filtered oil goes "out" through the center hole. The anti-drainback valve covers the input holes around the center. If you look at them and they seem covered, there is an anti-drainback valve in place. Ideally, any spin on filter would be installed with "screw up" so that it couldn't drain back helping oil pressure to come up more quickly after a cold start.

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Old 09-05-2016, 11:10 AM   #83
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I went to one the Yanmar engine maintenance classes at Mack Boring and they recommend "warm", i.e. run the engine for 10-15 minutes, heat the oil up a bit and then change it.
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Old 09-05-2016, 03:05 PM   #84
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Thanks so much for the very fine text and graphic display. One should be able to see the anti-drainback valve or diaphram through the holes outbd of center. Also one should be able to stick a tool in through the periphery holes.

Since on my last oil change the oil did'nt drain it must have the anti-drainback valve.

So there's no way I can drain the oil internally? Actually it seems I have never encountered a filter w a drainback valve as I always fill the filter w oil prior to installation. Maybe the filter # is for inverted filters that would'nt need a drainback valve. But then I only put "some" oiil in the horizontaly installed filters. But if the filter had the valve I wouldn't be able to pour any oil in .... what's the scoop?

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Old 09-05-2016, 03:08 PM   #85
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I'll bet it's hot for best change and warm for safety and comfort. Recomendations from sources like that tend to be "lawyer polished".


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