Re: Low Oil Pressure Guesses
 

"Will Honea" <whonea@yahoo.com> wrote in message
news:4638fb47$0$492$815e3792@news.qwest.net...
> Spdloader wrote:
>
>>> Somewhere back in foggy memory I remember an engine that had
>>> a ball and spring that kept the oil pressure regulated and one
>>> that bypassed the filter should it get cloged. But these days
>>> the bypass is built inside the filter.
>>>
>>> Might have been a Triumph?
>>>
>>> --
>>> DougW
>>
>> Oh, now I get it. The ball and spring you refer to is in the oil pump
>> housing. I noticed it when I made the replacement.
>
> That's the sucker. One thought: I replaced the oil pump in my 4L after it
> dropped something like 15 PSI across the board on one 175 mile run. When
> I
> pulled it, it was obvious that the problem was a break in that thin paper
> gasket between the pump body and the block. Since the old pump had
> 175,000
> miles on it, I went ahead and installed the new one anyway but I later ran
> a flow/pressure check on the old pump and it was still good - that one
> leaking gasket was apparently the whole problem. How careful were you
> about cleaning the surfaces when you mounted the new pump? It could be as
> simple as that. Small leaks on the high pressure side cause big problems.
>
> --
> Will Honea

Well, I was careful, I did not make it a top priority though. The old gasket
came off with the old pump, I wiped the mating surface with a shop towel
before slipping the new pump and gasket into place, but that's about it,
other than torqueing the pump bolts.
I have read before the bulletin about the gasket failure, but the old gasket
seemed fine to me.
Spdloader

Re: Low Oil Pressure Guesses
 

On Wed, 2 May 2007 06:32:13 -0500, "DougW"
<post.replies@invalid.address> wrote:

>Spdloader wrote:
>> "DougW" wrote
>
>>> Just a thought, but could the overpressure bypass spring be b0rked
>>> and sticking only when cold just to open up when warm?
>
>> Umm, huh?
>
>Somewhere back in foggy memory I remember an engine that had
>a ball and spring that kept the oil pressure regulated and one
>that bypassed the filter should it get cloged. But these days
>the bypass is built inside the filter.
>
>Might have been a Triumph?

yep - the 2.5L straight 6 in the TR6 has an oil pressure bypass that
screws into the side of the block. that's my other toy

reboot


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Re: Low Oil Pressure Guesses
 

On Wed, 2 May 2007 06:32:13 -0500, "DougW"
<post.replies@invalid.address> wrote:

>Spdloader wrote:
>> "DougW" wrote
>
>>> Just a thought, but could the overpressure bypass spring be b0rked
>>> and sticking only when cold just to open up when warm?
>
>> Umm, huh?
>
>Somewhere back in foggy memory I remember an engine that had
>a ball and spring that kept the oil pressure regulated and one
>that bypassed the filter should it get cloged. But these days
>the bypass is built inside the filter.
>
>Might have been a Triumph?

yep - the 2.5L straight 6 in the TR6 has an oil pressure bypass that
screws into the side of the block. that's my other toy

reboot


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Virus Database (VPS): 000738-0, 05/03/2007
Tested on: 5/2/2007 10:05:10 PM
avast! - copyright (c) 1988-2007 ALWIL Software.
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Re: Low Oil Pressure Guesses
 

On Wed, 2 May 2007 06:32:13 -0500, "DougW"
<post.replies@invalid.address> wrote:

>Spdloader wrote:
>> "DougW" wrote
>
>>> Just a thought, but could the overpressure bypass spring be b0rked
>>> and sticking only when cold just to open up when warm?
>
>> Umm, huh?
>
>Somewhere back in foggy memory I remember an engine that had
>a ball and spring that kept the oil pressure regulated and one
>that bypassed the filter should it get cloged. But these days
>the bypass is built inside the filter.
>
>Might have been a Triumph?

yep - the 2.5L straight 6 in the TR6 has an oil pressure bypass that
screws into the side of the block. that's my other toy

reboot


---
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Virus Database (VPS): 000738-0, 05/03/2007
Tested on: 5/2/2007 10:05:10 PM
avast! - copyright (c) 1988-2007 ALWIL Software.
http://www.avast.com

Re: Low Oil Pressure Guesses
 

On Wed, 2 May 2007 06:32:13 -0500, "DougW"
<post.replies@invalid.address> wrote:

>Spdloader wrote:
>> "DougW" wrote
>
>>> Just a thought, but could the overpressure bypass spring be b0rked
>>> and sticking only when cold just to open up when warm?
>
>> Umm, huh?
>
>Somewhere back in foggy memory I remember an engine that had
>a ball and spring that kept the oil pressure regulated and one
>that bypassed the filter should it get cloged. But these days
>the bypass is built inside the filter.
>
>Might have been a Triumph?

yep - the 2.5L straight 6 in the TR6 has an oil pressure bypass that
screws into the side of the block. that's my other toy

reboot


---
avast! Antivirus: Outbound message clean.
Virus Database (VPS): 000738-0, 05/03/2007
Tested on: 5/2/2007 10:05:10 PM
avast! - copyright (c) 1988-2007 ALWIL Software.
http://www.avast.com

Re: Low Oil Pressure Guesses
 

Have you tried to change the oil filter with one of a different
manufacturer?
You may have a defective one.

It is unusual to have worn-out bearings at 77k miles.
I have a '96 XJ with 2.5l, ex-police car with 220k miles on it that has
still normal oil pressure.
If the car was not extremely abused, or ran without oil, or ran for
sustained periods with low oil pressure, then the bearings would not be my
first guess.

If you remove the oil pan, you can remove a rod cap to check the condition
of a rod bearing. They are the ones that get shot first. If the copper layer
is exposed in the rod bearings, then they will need replacement. That's a
relatively easy job to do it yourself and replacement bearing shells are
relatively cheap. You will need a good torque wrench and a collection of
socket extensions to re-torque the rod-caps.

Good luck.


"Spdloader" <askforit@nospam.triad.rr.com> wrote in message
news:46377996$0$5619$4c368faf@roadrunner.com...
> Wife's '97 TJ, 2.5eng., 77,000 miles.
>
> Never been under water, or overheated.
>
> Oil always changed at 3500mile intervals.
>
> Problem: It has low oil pressure after warm up.
>
> Cold (ambient, 65deg.) pressure is 45psi. After warm up, it cruises around
> 25-30psi then it idles down to "0", and all the check gauges lights all
> come on. Pressure confirmed within a psi or two with a "live" gauge.
> Tapping the throttle obviously raises the pressure slightly, and lights go
> off. Running the A/C helps increase the idle slightly, increasing pressure
> slightly.
>
> Hoping but not really believing it would work, I changed the oil pump,
> which made no difference whatsoever. I switched to straight 30W oil, which
> has a higher cold start pressure, but makes no difference after warm up.
>
> I don't really want to change the engine, but it would be easier than
> putting in new main, rod, and cam bearings.
>
> Any other ideas, or is there something about these 2.5's I've missed?
>
> Spdloader
>

Re: Low Oil Pressure Guesses
 

Have you tried to change the oil filter with one of a different
manufacturer?
You may have a defective one.

It is unusual to have worn-out bearings at 77k miles.
I have a '96 XJ with 2.5l, ex-police car with 220k miles on it that has
still normal oil pressure.
If the car was not extremely abused, or ran without oil, or ran for
sustained periods with low oil pressure, then the bearings would not be my
first guess.

If you remove the oil pan, you can remove a rod cap to check the condition
of a rod bearing. They are the ones that get shot first. If the copper layer
is exposed in the rod bearings, then they will need replacement. That's a
relatively easy job to do it yourself and replacement bearing shells are
relatively cheap. You will need a good torque wrench and a collection of
socket extensions to re-torque the rod-caps.

Good luck.


"Spdloader" <askforit@nospam.triad.rr.com> wrote in message
news:46377996$0$5619$4c368faf@roadrunner.com...
> Wife's '97 TJ, 2.5eng., 77,000 miles.
>
> Never been under water, or overheated.
>
> Oil always changed at 3500mile intervals.
>
> Problem: It has low oil pressure after warm up.
>
> Cold (ambient, 65deg.) pressure is 45psi. After warm up, it cruises around
> 25-30psi then it idles down to "0", and all the check gauges lights all
> come on. Pressure confirmed within a psi or two with a "live" gauge.
> Tapping the throttle obviously raises the pressure slightly, and lights go
> off. Running the A/C helps increase the idle slightly, increasing pressure
> slightly.
>
> Hoping but not really believing it would work, I changed the oil pump,
> which made no difference whatsoever. I switched to straight 30W oil, which
> has a higher cold start pressure, but makes no difference after warm up.
>
> I don't really want to change the engine, but it would be easier than
> putting in new main, rod, and cam bearings.
>
> Any other ideas, or is there something about these 2.5's I've missed?
>
> Spdloader
>

Re: Low Oil Pressure Guesses
 

Have you tried to change the oil filter with one of a different
manufacturer?
You may have a defective one.

It is unusual to have worn-out bearings at 77k miles.
I have a '96 XJ with 2.5l, ex-police car with 220k miles on it that has
still normal oil pressure.
If the car was not extremely abused, or ran without oil, or ran for
sustained periods with low oil pressure, then the bearings would not be my
first guess.

If you remove the oil pan, you can remove a rod cap to check the condition
of a rod bearing. They are the ones that get shot first. If the copper layer
is exposed in the rod bearings, then they will need replacement. That's a
relatively easy job to do it yourself and replacement bearing shells are
relatively cheap. You will need a good torque wrench and a collection of
socket extensions to re-torque the rod-caps.

Good luck.


"Spdloader" <askforit@nospam.triad.rr.com> wrote in message
news:46377996$0$5619$4c368faf@roadrunner.com...
> Wife's '97 TJ, 2.5eng., 77,000 miles.
>
> Never been under water, or overheated.
>
> Oil always changed at 3500mile intervals.
>
> Problem: It has low oil pressure after warm up.
>
> Cold (ambient, 65deg.) pressure is 45psi. After warm up, it cruises around
> 25-30psi then it idles down to "0", and all the check gauges lights all
> come on. Pressure confirmed within a psi or two with a "live" gauge.
> Tapping the throttle obviously raises the pressure slightly, and lights go
> off. Running the A/C helps increase the idle slightly, increasing pressure
> slightly.
>
> Hoping but not really believing it would work, I changed the oil pump,
> which made no difference whatsoever. I switched to straight 30W oil, which
> has a higher cold start pressure, but makes no difference after warm up.
>
> I don't really want to change the engine, but it would be easier than
> putting in new main, rod, and cam bearings.
>
> Any other ideas, or is there something about these 2.5's I've missed?
>
> Spdloader
>

Re: Low Oil Pressure Guesses
 

Have you tried to change the oil filter with one of a different
manufacturer?
You may have a defective one.

It is unusual to have worn-out bearings at 77k miles.
I have a '96 XJ with 2.5l, ex-police car with 220k miles on it that has
still normal oil pressure.
If the car was not extremely abused, or ran without oil, or ran for
sustained periods with low oil pressure, then the bearings would not be my
first guess.

If you remove the oil pan, you can remove a rod cap to check the condition
of a rod bearing. They are the ones that get shot first. If the copper layer
is exposed in the rod bearings, then they will need replacement. That's a
relatively easy job to do it yourself and replacement bearing shells are
relatively cheap. You will need a good torque wrench and a collection of
socket extensions to re-torque the rod-caps.

Good luck.


"Spdloader" <askforit@nospam.triad.rr.com> wrote in message
news:46377996$0$5619$4c368faf@roadrunner.com...
> Wife's '97 TJ, 2.5eng., 77,000 miles.
>
> Never been under water, or overheated.
>
> Oil always changed at 3500mile intervals.
>
> Problem: It has low oil pressure after warm up.
>
> Cold (ambient, 65deg.) pressure is 45psi. After warm up, it cruises around
> 25-30psi then it idles down to "0", and all the check gauges lights all
> come on. Pressure confirmed within a psi or two with a "live" gauge.
> Tapping the throttle obviously raises the pressure slightly, and lights go
> off. Running the A/C helps increase the idle slightly, increasing pressure
> slightly.
>
> Hoping but not really believing it would work, I changed the oil pump,
> which made no difference whatsoever. I switched to straight 30W oil, which
> has a higher cold start pressure, but makes no difference after warm up.
>
> I don't really want to change the engine, but it would be easier than
> putting in new main, rod, and cam bearings.
>
> Any other ideas, or is there something about these 2.5's I've missed?
>
> Spdloader
>

Update
 

"Spdloader" <askforit@nospam.triad.rr.com> wrote in message
news:46377996$0$5619$4c368faf@roadrunner.com...
> Wife's '97 TJ, 2.5eng., 77,000 miles.
>
> Never been under water, or overheated.
>
> Oil always changed at 3500mile intervals.
>
> Problem: It has low oil pressure after warm up.
>
> Cold (ambient, 65deg.) pressure is 45psi. After warm up, it cruises around
> 25-30psi then it idles down to "0", and all the check gauges lights all
> come on. Pressure confirmed within a psi or two with a "live" gauge.
> Tapping the throttle obviously raises the pressure slightly, and lights go
> off. Running the A/C helps increase the idle slightly, increasing pressure
> slightly.
>
> Hoping but not really believing it would work, I changed the oil pump,
> which made no difference whatsoever. I switched to straight 30W oil, which
> has a higher cold start pressure, but makes no difference after warm up.
>
> I don't really want to change the engine, but it would be easier than
> putting in new main, rod, and cam bearings.
>
> Any other ideas, or is there something about these 2.5's I've missed?
>
> Spdloader

Well, the TJ went off to the dealer, traded in for a brand new '07 Wrangler
Unlimited Sahara.
She got just what she wanted, she says.
We were open with the dealer about the low oil pressure issue, and they
didn't seem to care. They really wanted that TJ.
So, I don't have any info on the actual cause at this point, they assured me
they'd fix it and let me know. Apparently, the son of the dealer wanted our
old one, so they are going to fix it.

Spdloader