So I permanantly blocked my oil filter bypass

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ME 109
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So I permanantly blocked my oil filter bypass

Post by ME 109 »

Oil filter bypass spring failure yet again, has forced me to block the bypass with a 12 x 1.5 plug.
The spring seat is beyond repair due to the ball thrashing around in the cavity. The seat was damaged the first time around and now there is more damage and another broken spring. The spring seat is very close to the gallery behind, so not much meat to work with.
There may be the possibility of finding, adapting and fitting another bypass valve. There's one on my coffee pot for example that if bigger, could quite possibly work.
I have't google yet but discussed the possibilities with Charlie last night.
Anyway, for now the bypass is blocked.

What can happen?
I can see the white oring could blow out, or maybe the oil pump cover plate could bow until oil escaped.
Where else could it blow off pressure, between the oil pump and outlet from the filter cavity?
I spose it could blow out the oil cooler radiator if the thermostat was open.
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gspd
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Re: So I permanantly blocked my oil filter bypass

Post by gspd »

WHOA! This is a new one!!!I that's the only thing preventing the oil pressure from going sky high.
It acts like a pressure regulator. have you run it yet?
Seeing as your engine is not new, maybe it'll just bleed off pressure internally, around the main and rod bearings and such.
but maybe not. I doubt it.
Theoretically, it could go into 4 digit pressures (1000 psi or more) which could break the cam (or worse) if the pump jams from too much pressure.(normal max is maybe 150psi cold with thick oil)
Try installing a pressure gauge in the oil switch hole and see what it reads when cold, when hot and at different rpm's.
Maybe it's time you start looking for a new bottom end or a really good machinist to fix it.
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robert
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Re: So I permanantly blocked my oil filter bypass

Post by robert »

GSPD, his problem is the oil filter bypass valve. The most that could happen is the filter could fail.
You must be thinking of the pressure regulator on the front of the motor.
ME 109
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Re: So I permanantly blocked my oil filter bypass

Post by ME 109 »

Oil filter bypass, not the oil pressure relief valve.
Everything after the oil filter cavity is ok.
But the oil filter cavity outlets are now compromised with the bypass hole blocked.
If the oil filter is changed with oil at every 5k's, it should be ok.
If the filter blocked, there's nowhere for the oil to go, except the white oring, cooler radiator or pump cover.

I did 300 k's on it yesterday without issue.

I had an idea to remake a spring seat in the bypass cavity from part of a neutral switch. Same size thread as the ally retainer plug, plus with a hole in it. Perfect.
That required the 12 x 1.5mm thread to be extended all the way to the bottom of the bypass cavity, so I could screw a new seat all the way down. I could have then used the oe ball and retainer plug with possibly a modified spring, and produce a working bypass.
I abandoned that idea because I was not overly happy with the condition of the bypass cavity for me to produce a satisfactory thread.

It's a case killer, this bypass situation. I just saw Rob post but I'll post this anyway.
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ME 109
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Re: So I permanantly blocked my oil filter bypass

Post by ME 109 »

robert wrote: Sat Jul 28, 2018 11:43 pm The most that could happen is the filter could fail.
So the paper blows through in one or more areas until enough unrestricted flow is achieved?
That sounds better than kaboom, especially at high rpm in top gear.
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gspd
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Re: So I permanantly blocked my oil filter bypass

Post by gspd »

OOPS! MY BAD! so sorry
I was thinking oil pressure relief, not oil filter bypass
Image
you meant here, right?
Image
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gspd
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Re: So I permanantly blocked my oil filter bypass

Post by gspd »

I don't think you'll have a problem if you change your filter regularly.
99% sure that valve is just there in case the oil filter becomes blocked.
not 100% sure though :oops:
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ME 109
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Re: So I permanantly blocked my oil filter bypass

Post by ME 109 »

Yeah, parts 14-15-16
Possibly the rarest failure of the 247 with possibly disastrous consequences for the crank, main and big end journals.
You might recall the first time this happened, maybe eight years ago. A couple small bits of broken bypass spring killed the rear main journal.

The bypass is for blocked filters and will pass an increasing amount of oil as the filter further clogs.
It's said that the bypass will open on a cold start. If that's the case it will stay open until the oil thins sufficiently that the filter can handle all the oil flow and the bypass closes. That could be several minutes.
I don't think there is any sudden overwhelming oil flow that opens the bypass just at start up. If the oil filter can handle all the flow at higher rpm, it will handle any flow at start up. So I think there might be a bit of a myth?
And, I can't see how anyone can know when the bypass opens, it can't be seen and will not show a different oil pressure, open or closed.
The % blockage of the filter is the only sliding scale for the valve to open. Once that % blocked reaches the threshold, and opens the bypass, it will always be open when the engine is running, and will open further as the filter further clogs.

This is what I think I've learned, about the situation. I wanted to find out what failures could occur, and what could break, and cause significant issues at speed.
If the filter pleat material can be minced through the holes in the oil filter's metal frame, that would be preferable to some sort of hydraulic lock up.
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Zombie Master
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Re: So I permanantly blocked my oil filter bypass

Post by Zombie Master »

Here's where a 100% synthetic oil could be a real advantage, as they flow so well when cold.
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ME 109
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Re: So I permanantly blocked my oil filter bypass

Post by ME 109 »

Zombie Master wrote: Sun Jul 29, 2018 4:28 am Here's where a 100% synthetic oil could be a real advantage, as they flow so well when cold.
I've been thinking this. Beemerboff swears by his brand, Mobil I think, I really should remember which one by now.
I'd consider swapping from Penrite, given the circumstances.
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