Any reason for low oil press at low rpm besides the pump?
muzician21
on today at low rpm - basically below about 800 rpm, particularly when
in gear. Assuming the sensor is correct, is there any reason for this
besides the oil pump? The engine only has about 40k miles since a
rebuild, re-used the old oil pump which I assume is the original. Car
has about 150k miles on it.
What's the life expectancy of these pumps?
Besides Ebay any good source for parts? Dealer wants most of $300 for
one, the auto parts places apparently don't have it.
Thanks for all input.
Jeff Strickland
"muzician21" <muzic...@yahoo.com> wrote in message
news:fe305f70-bdc0-47e5...@w19g2000yqk.googlegroups.com...
Worn out bearings and seals cal let the oil pressure drop.
The rule of thumb is that you need 10psi of pressure for every 1000 rpm.
Mike Hunter
"Jeff Strickland" <crwl...@yahoo.com> wrote in message
news:hekf4a$j8c$1...@news.eternal-september.org...
Steve Austin
Lol. Got a Fram filter on it? (As I duck for cover)
Jeff Strickland
"Mike Hunter" <Mikehunt2@lycos,com> wrote in message
news:4b0dc35b$0$19746$ce5e...@news-radius.ptd.net...
Tegger
@news.westelcom.com:
The oil filter should present a restriction to oil flow that is LESS than
the restriction created by bottom-end bearing clearances, even at maximum
engine speed or at extreme low temperatures.
The bearings get their pressure from the oil pump. If the filter is a
restriction, the bearings will be starved for oil and the reported pressure
will be low.
I won't use FRAM, but inadequate oil pressure is not the reason why.
--
Tegger
Hachiroku ハチロク
AARRRGGGGGHHHHHH!!!!!!!!!!!!
(I bet he does!)
Hachiroku ハチロク
Spec:
http://www.cygnusx1.net/Supra/Library/TSRM/MK3/manual.aspx?Section=LU&P=4
6. Measure Oil Pressure
Oil pressure:
At idle speed: 0.3 kg/cm3 (4.3 psi)
At 3,000 RPM: 2.5 - 5.0 kg/cm#
(36 - 71 psi)
This engine has kind of a low spec. My Supra has an oil pressure gauge,
and if it's accurate at all, my car falls in spec. I think it's low, but
it's in spec.
NOTE: after hard driving with the engine fully warm, oil pressure will
drop a bit. Use a heavier weight oil like 10-40 or 'diesel' oil, 15-40.
Hachiroku ハチロク
What did you do for a rebuild?
Also, why rebuild an engine and not replace the oil pump?!?!?
That engine is a real PITA to get to the oil pump! Should have done it
when you had the engine out!
fred
> "Mike Hunter" <Mikehunt2@lycos,com> wrote in message
> news:4b0dc35b$0$19746$ce5e...@news-radius.ptd.net...
>>
>> news:hekf4a$j8c$1...@news.eternal-september.org...
>>>
>>> "muzician21" <muzic...@yahoo.com> wrote in message
>>> news:fe305f70-bdc0-47e5...@w19g2000yqk.googlegroups.com.
>>> ..
>>>> 89 Cressida w/7MGE - I just started seeing my oil pressure light
>>>> going on today at low rpm - basically below about 800 rpm,
>>>> particularly when in gear. Assuming the sensor is correct, is there
>>>> any reason for this besides the oil pump? The engine only has about
>>>> 40k miles since a rebuild, re-used the old oil pump which I assume is
>>>> the original. Car has about 150k miles on it.
>>>>
>>>> What's the life expectancy of these pumps?
>>>>
>>>> Besides Ebay any good source for parts? Dealer wants most of $300 for
>>>> one, the auto parts places apparently don't have it.
>>>>
>>>> Thanks for all input.
>>>
>>>
>>> Worn out bearings and seals cal let the oil pressure drop.
>>>
>>> The rule of thumb is that you need 10psi of pressure for every 1000
>>> rpm.
>> As well as worn main bearings
>>
> Didn't I say that?
>
It always seems to be top-posters doesn't it?
Tegger
in news:pan.2009.11.26....@e86.GTS:
That would make zero difference to oil pressure.
--
Tegger
Jeff Strickland
"Hachiroku ????" <Tru...@e86.GTS> wrote in message
news:pan.2009.11.26....@e86.GTS...
If all you want is high pressure, use 20w50. I used 20w50 in my Jeep for
summer in Southern California, but I'm positive that if 20w50 works for
anybody anywhere else in the world, engine troubles are close at hand. I
found the 20w50 in my 258 Inline 6 was slow to get to the top of the motor.
I used it exactly one oil change. The upside is, the leaks stopped while I
used it.
The spec you give is a little under 10psi per 1000rpm at idle and a bit over
at highway speeds. Since the question is about idle speed pressure dropping,
if he's got 10psi at idle, then all is well in his universe.
Jeff Strickland
> It always seems to be top-posters doesn't it?
>
>
>
>> Didn't I say that?
>>
>>
>>> As well as worn main bearings
>>>
"fred" <fr...@bedrock.rock> wrote in message
news:Xns9CCED46...@127.0.0.1...
muzician21
> The oil filter should present a restriction to oil flow that is LESS than
> the restriction created by bottom-end bearing clearances, even at maximum
> engine speed or at extreme low temperatures.
I first noticed it today at a stoplight and it was still doing it
after it had been sitting all day and fired up and idling in the
parking lot.
Since making my original post, after a filter change and refill with
5W-40 Mobil 1, and about 30 - 45 mins of around town go-to-store, fire
it up again go to another store driving, for the moment I haven't seen
the light come back on again - might have been a mucked up filter.
Will take a longer down the highway run later and then see what
happens.
I appreciate everyone's input.
Jeff Strickland
<JS>
My input is that you have selected oil that's pretty light, and this will
give you low oil pressure.
</JS>
Hachiroku ハチロク
>>> Lol. Got a Fram filter on it? (As I duck for cover)
>>
>> AARRRGGGGGHHHHHH!!!!!!!!!!!!
>>
>> (I bet he does!)
>>
>>
>
>
> That would make zero difference to oil pressure.
See the other thread. I have been having oil press probs on two cars
consistantly since installing Frams on them. One is a Supra, 7M-GE, same
engine as the OP. When I was using OEM Toyota filters, no problem...
Steve W.
Install a REAL oil pressure gauge and see what you have.
The spec I found here says 15W-40 oil for that engine for normal use and
5W-30 for extreme COLD weather use.
--
Steve W.
Ray O
When the low oil pressure warning light comes on, the first thing to check
is oil volume with the dipstick to make sure there is sufficient oil in the
oil pan.
Next, check the oil sender for leaks because a visual check costs nothing,
even though the symptoms you are describing don't point to a leaking oil
sender.
Is the oil sender is not leaking, remove the sender and install an oil
pressure gauge to measure actual oil pressure, using the figures hachiroku
posted.
Whoever rebuilt the engine should have measured the clearances between the
impeller, crescent, and body of the oil pump before reusing it. Whatever
caused the original engine to fail could have also caused oil pump wear.
The other thing to do when rebuilding an engine is to plasti-gauge the main
and connecting rod bearings to make sure there isn't excess clearance, which
can cause low oil pressure.
--
Ray O
(correct punctuation to reply)
Hachiroku ハチロク
>> Thanks for all input.
>
> Install a REAL oil pressure gauge and see what you have.
>
> The spec I found here says 15W-40 oil for that engine for normal use and
> 5W-30 for extreme COLD weather use.
Wow. For a 7M-GE?!?!?
Hachiroku ハチロク
I'll be dipped!
Engine Oil
Recommended viscosity: 20-100F 15w40-20w50, 0-80F 10w30-10w50, 50F and
below 5w30
I've been running 10W-40, and I only use the car in the summer.
Jeff Strickland
"muzician21" <muzic...@yahoo.com> wrote in message
news:fe305f70-bdc0-47e5...@w19g2000yqk.googlegroups.com...
Autoparts places have the oil pump ...
http://shop.oreillyauto.com/ProductDetail.aspx?MfrCode=CLE&MfrPartNumber=6012060
It probably costs more than the car is worth, but if your heart is set on
buying a new pump, they are out there.
m6onz5a
I was going to ask if you were using a cheap oil, or have you always
used Mobil1?
Vic Smith
<roki...@NOSPAMtristarassociates.com> wrote:
>
>"muzician21" <muzic...@yahoo.com> wrote in message
>news:fe305f70-bdc0-47e5...@w19g2000yqk.googlegroups.com...
>> 89 Cressida w/7MGE - I just started seeing my oil pressure light going
>> on today at low rpm - basically below about 800 rpm, particularly when
>> in gear. Assuming the sensor is correct, is there any reason for this
>> besides the oil pump? The engine only has about 40k miles since a
>> rebuild, re-used the old oil pump which I assume is the original. Car
>> has about 150k miles on it.
>>
>> What's the life expectancy of these pumps?
>>
>> Besides Ebay any good source for parts? Dealer wants most of $300 for
>> one, the auto parts places apparently don't have it.
>>
>> Thanks for all input.
>
>When the low oil pressure warning light comes on, the first thing to check
>is oil volume with the dipstick to make sure there is sufficient oil in the
>oil pan.
>
And make sure you're checking the oil, not the trans.
Believe me, it happens.
--Vic