Too much oil pressure? If so, how/why?

ill advised

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Over the past 1 1/2 weeks I've had two major oil spills at the filter. Apparently I'm having a problem with excess pressure. My filter looks like an unopend soda can that's been in the freezer too long. It doesn't actually "burst" but the damage obviously allows oil to escape. I was told that there could be an obstruction in the oil pump bypass. I'm still on the stock bottom end, which now has 299k miles on it (that includes everything except the rings, cam & bearings). On both occassions the filter ruptured while the car was sitting and "cool". Actually the first time I didn't realize it had happend until I saw my oil guage reading 0 pressure.

I recently installed new lifters/pushrods after one of my lifters broke. That lead to other things and the car sat for 5 months. Everything seems fine when I drive the car, oil pressure is normal.

The first filter:



 
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dastang2

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have you checked and cleaned the pcv valve, if not working correctly oil can be pushed out of the seals and dipstick tube by access crankcase pressures.
 

Rick 91GT

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PCV? Huh.... unrelated issue...

Yes definitly have a excessive pressure issue, usually you blow off filters if the filter is a junk filter or if you have a ton of oil pressure. The FL1A filters are nice pieces, and you have normal pressure while running so that is not the issue most likely.

You could have a blockage in the bypass but I would think that would show on the gauge...I'll do some digging and see what I can come up with.
 

battyice

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I would say your oil pump's bypass spring is malfunctioning. Some of the early 4.6's in Crown Victorias were known for having the bypass spring stick and the oil filters buldge out like yours.
 

ill advised

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Yeah I hoped that I just had a bad filter the first time. Both were FL1As. The second filter I put in Thursday evening and drove the car to work that Friday (10 miles round trip).

I drove it all day Saturday as well. Sunday morning I moved the car to the street and it was still ok. No leaking at all, so I wrote it off as a bad filter. Fast forward to this morning, I see the puddle of oil and have no oil pressure.
 

dastang2

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ok i really was going to say something about a release spring or whatnot but i really don't know much about them so i didn't.he said he had oil leaks so i mentioned pcv. sorry.
 

Rick 91GT

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No prob dastang just didn't want him going down the wrong path searching for a cure that won't happen.

I think it's the relief spring, with that many miles I would say that pump was very, very good to you. Can you afford a rebuild, I bet it is time for new rings and bearings...
 

ill advised

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I hear you Rick. I do have enough for a rebuild but the "dream" is to ditch the old block for a new stroker at some point. Unfortanately I can't afford that just yet. I agree though, I've definately gotten my money's worth and at this point I've been on borrowed time. lol Honestly, right now I'm just trying to keep the car running until I'm ready to make the jump.

Just so I'm clear: is the relief spring part of the oil pump or a seperate piece altogether? Better yet, do I need to install a new oil pump? (which from what I hear is no picnic) :mad:
 

Rick 91GT

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The spring is internal to the pump, so yes a new pump is in order. Awesome job getting that kind of mileage out of a motor.

Yes I find it easier just to yank the motor to do anything that involves pulling the oil pan, that is whay I asked about a rebuild. I would say just hone it, put new rings and bearings but with the high mileage I am sure the bores have a tapere which means it should be bored.
 

UMDSmith

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At 299k I'd say you were past borrowed time and into stolen time.:) It definatly is a pump issue. Just out of curiosity, what viscosity oil are you running currently?
 

tmoss

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The bypass should only come into play if the filter is clogged right? If it's stuck shut, the filter should still relieve enough pressure with a good filter to stop that - and these filters were relatively new. I agree about the question of viscosity - maybe this happens with a cold engine and high viscosity oil?
 

blk92stangg

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Could not the blockage be right at the oil filter mounting point ,maybe after the pressure sensor? As in oil flows in, but can't flow out? If the media inside the filter had gotten plugged, I would think the media itself would rupture before the bulging of the filter case, therefore reducing the pressure build up. I am ignorant about that spring relief valve you guys are talking about, but would the stuck valve really do that to a filter? If the filter was new, that valve would be non issue? Or is that what Tmoss was referring too? That is nuts lol, and I totally curious to know what's going on.
 

HISSIN50

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blk92stangg said:
Could not the blockage be right at the oil filter mounting point ,maybe after the pressure sensor? As in oil flows in, but can't flow out? If the media inside the filter had gotten plugged, I would think the media itself would rupture before the bulging of the filter case, therefore reducing the pressure build up. I am ignorant about that spring relief valve you guys are talking about, but would the stuck valve really do that to a filter? If the filter was new, that valve would be non issue? Or is that what Tmoss was referring too? That is nuts lol, and I totally curious to know what's going on.
Blk, im not too good with this stuff either. i know Tom is (i posted a thread involving the relief mechanism awhile back, and he was kind enough to respond). :nice:

as i understand it, when the pressure differential between the incoming and outgoing oil in the filter reaches a certain threshold, the relief opens. this is for when a filter gets clogged, so you can keep flowing oil. the downside is that you are running with no filtering. im sure all the other guys can give more info - im curious too.