Oil pressure dropping to less than 20
11-19-2013, 01:49 PM
#31
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Year: 1998 Sport
Model: Cherokee
Engine: 4.0
I'm not sure, but I gather that you are not a fan of the cheapest oil filter made?
I took the OSU off and cleaned the hole with some carb spray and ran the tube down into the passage. Inspected it with a mirror and it was/is clean.
Scratching my head this morning, I realized that I had a gauge for my compressor, so I taped it up and screwed it in. at start it reads 30psi.
Replaced the sending unit and it reads 30 psi as well.
I'd much rather spend the $10 on the NAPA than replace the pump, if that is really what y'all think. Even if it doesnt' work, I'm still putting on a better filter.
I took the OSU off and cleaned the hole with some carb spray and ran the tube down into the passage. Inspected it with a mirror and it was/is clean.
Scratching my head this morning, I realized that I had a gauge for my compressor, so I taped it up and screwed it in. at start it reads 30psi.
Replaced the sending unit and it reads 30 psi as well.
I'd much rather spend the $10 on the NAPA than replace the pump, if that is really what y'all think. Even if it doesnt' work, I'm still putting on a better filter.
11-19-2013, 02:00 PM
#32
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Year: 1989
Model: Cherokee
Engine: 4.0 i6
Time for a new oil pump? Dang thing is running at just over 40 until it gets hot, then it drops to 20 at cruise. Come to idle and the pressure is a little over 15.
I have a new pump on the way, is there something else I should be looking for/at?
The old girl has 223 on the clock.
I have a new pump on the way, is there something else I should be looking for/at?
The old girl has 223 on the clock.
That oil pressure seems right.
11-19-2013, 02:45 PM
#33
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Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
I'm not sure, but I gather that you are not a fan of the cheapest oil filter made?
I took the OSU off and cleaned the hole with some carb spray and ran the tube down into the passage. Inspected it with a mirror and it was/is clean.
Scratching my head this morning, I realized that I had a gauge for my compressor, so I taped it up and screwed it in. at start it reads 30psi.
Replaced the sending unit and it reads 30 psi as well.
I'd much rather spend the $10 on the NAPA than replace the pump, if that is really what y'all think. Even if it doesnt' work, I'm still putting on a better filter.
I took the OSU off and cleaned the hole with some carb spray and ran the tube down into the passage. Inspected it with a mirror and it was/is clean.
Scratching my head this morning, I realized that I had a gauge for my compressor, so I taped it up and screwed it in. at start it reads 30psi.
Replaced the sending unit and it reads 30 psi as well.
I'd much rather spend the $10 on the NAPA than replace the pump, if that is really what y'all think. Even if it doesnt' work, I'm still putting on a better filter.
11-19-2013, 02:45 PM
#34
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Year: 1990
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11-20-2013, 01:28 PM
#36
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Year: 1997
Model: Cherokee
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I don't mean to hijack but, I read on several posts here that using a Mopar filter, Napa Gold/Wix would increase oil pressure. I had a Fram on mine and my last oil change I went with the Mopar filter. I will say that it made one heck of a difference! I honestly didn't believe it at first but, I am a believer now and will always use a QUALITY filter.
11-20-2013, 04:27 PM
#37
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Year: 1990
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I don't mean to hijack but, I read on several posts here that using a Mopar filter, Napa Gold/Wix would increase oil pressure. I had a Fram on mine and my last oil change I went with the Mopar filter. I will say that it made one heck of a difference! I honestly didn't believe it at first but, I am a believer now and will always use a QUALITY filter.
11-20-2013, 04:29 PM
#38
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11-20-2013, 05:59 PM
#40
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11-20-2013, 06:33 PM
#41
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Year: 1999
Model: Cherokee
Engine: 4.0L OBD-II
You want to know why we don't like FRAM?
http://www.minimopar.net/oilfilters/index.html
Plenty of videos on the Youtubs showing their poor construction, but not much in the way of "why" they're bad as filters aside from that.
http://www.minimopar.net/oilfilters/index.html
Plenty of videos on the Youtubs showing their poor construction, but not much in the way of "why" they're bad as filters aside from that.
11-20-2013, 07:13 PM
#42
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Year: '98
Engine: 4.0 I6
I changed from fram + mystery dirty oil when I first bought my Jeep, to a mopar filter + Rotella T6 and went from 15psi hot idle to 20+psi hot idle, and 30psi cruise to 40psi cruise.
Quite happy with the results, but it could have been moving to fresh w40 oil that accounted for most of the change.
I am going to run an oversized filter next time and see what happens. I feel like lower resistance will slightly decrease oil pressure but increased flow. Not sure if that is good or bad though...
Quite happy with the results, but it could have been moving to fresh w40 oil that accounted for most of the change.
I am going to run an oversized filter next time and see what happens. I feel like lower resistance will slightly decrease oil pressure but increased flow. Not sure if that is good or bad though...
11-20-2013, 08:21 PM
#43
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Year: 1999
Model: Cherokee
Engine: 4.0L OBD-II
It's a very good thing. The oil pressure sending unit is located downstream of the filter, so when it shows higher pressure that's an indication that oil is being pushed through the filter instead of onto a very restrictive filter. Generally speaking, if you want a filter that's effective AND flows well, more surface area is key. Oversized units like the WIX 51452 (rugged version of the 51515) are a great choice for this reason, it's not JUST about contaminant capacity, you get more oil, too!
11-20-2013, 09:08 PM
#44
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Year: 1994
Model: Grand Cherokee
Engine: v8
Before you do anything drastic, take that POS out, take a hammer and beat the **** out of it. Then, have a nice cold beer and put a decent filter in there. NAPA Gold is a good option.
Unless you particularly enjoy replacing oil pumps in Jeeps, I suggest you get the engine nice and hot and measure the pressure using a mechanical gauge. Also, make sure you keep the receipt for that oil pump since you'll most probably will be returning it.
Unless you particularly enjoy replacing oil pumps in Jeeps, I suggest you get the engine nice and hot and measure the pressure using a mechanical gauge. Also, make sure you keep the receipt for that oil pump since you'll most probably will be returning it.
Fram-Lover:
ETA; Please don't call EPA on me. I had several cold beers before I heeded your advice, so you have some complicity.
11-20-2013, 09:12 PM
#45
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Year: 1994
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All fun aside, I still need to get dirty.
After the filter change, it still isn't breaking 40 and is running at 15 or less when hot.
Something is wrong when it goes from 50/30 to 30/15 in 6 months. Not sure what, but I have tried the easy/cheap things.
After the filter change, it still isn't breaking 40 and is running at 15 or less when hot.
Something is wrong when it goes from 50/30 to 30/15 in 6 months. Not sure what, but I have tried the easy/cheap things.