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1991 5.0 burning oil

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Jonathan Dlouhy

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Mar 15, 1997, 3:00:00 AM3/15/97
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Sorry if this topic has already been covered. I've got a 1991 5.0
coupe with 80,000 miles that's started burning oil at the rate of 1
quart per 2000 miles. Is this normal for these engines? If so, any
guesses as to the rate at which this situation will get worse?

Thanks,
Jonathan Dlouhy
Principal Oboe, A.S.O.
dlo...@mindspring.com
Evolution is God's way of issuing upgrades

TrueStreeter

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Mar 15, 1997, 3:00:00 AM3/15/97
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Just Normal, some cars ive seen have burned oil from the day they left
the Ford Dealership, some dont burn any oil at all. I wouldnt worry
about it. My own car consumes about the same, ive run a compression test
which found nothing wrong and it hasnt affected the performance so i
just live with it

Gary H

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Mar 15, 1997, 3:00:00 AM3/15/97
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>Just Normal, some cars ive seen have burned oil from the day they left
>the Ford Dealership, some dont burn any oil at all. I wouldnt worry
>about it. My own car consumes about the same, ive run a compression test
>which found nothing wrong and it hasnt affected the performance so i
>just live with it

Yup. I bought a '91 Cougar XR7 5.0 HO in Dec. of '94. It had about
45,000 miles on it, and it burned oil It seemed to burn a little more
the harder I drove it. My Dad was a little concerned at first, but it
never got any worse so it was no big deal. I just sold that car tomy
brother, it has 98,000 on it, and its fine. I guess its just normal,
and don't worry about it.

Pentium_Man

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Mar 16, 1997, 3:00:00 AM3/16/97
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dlo...@mindspring.com (Jonathan Dlouhy) wrote:

>Sorry if this topic has already been covered. I've got a 1991 5.0
>coupe with 80,000 miles that's started burning oil at the rate of 1
>quart per 2000 miles. Is this normal for these engines? If so, any

That's not bad at all!! I'll bet most 5.0's go through 1QT every 1,000 miles

clarkms

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Mar 16, 1997, 3:00:00 AM3/16/97
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Jonathan Dlouhy wrote:
>
> I've got a 1991 5.0 coupe with 80,000 miles that's started
> burning oil at the rate of 1 quart per 2000 miles. Is this
> normal for these engines?

It is my understanding that Ford considers it "normal" for a pre-1993
5.0L to use oil, and one quart every 2,000 miles is well within the
acceptable range of "normal operation." At 80,000 miles, it is unlikely
(though admittedly not impossible) that your car's oil-burning tendency
developed "suddenly" -- the 5.0L engine has always been notorious for
burning some oil between changes, and most 5.0L owners will tell you
that their car has burned some amount of oil since it was new. However,
if your engine burned no oil and suddenly started (which seems unlikely
absent an identifiable event), then you probably should have the engine
checked.

My personal experience with five 5.0L Mustangs (various model years, '79
through '93) has led me to conclude that, if properly maintained and not
regularly raced, the 5.0L engine block components are usually good for
at least 150,000 miles with no major problems... so, 80,000 is really
just "broke in good." Of those Mustangs, only one burned oil at the rate
of one quart every 1,500 miles -- that was an '89 ragtop that burned oil
from the time it was new (the rate of oil consumption increased
gradually from 1/2 quart every 3,000 miles to nearly a quart every 1,500
miles over its first 65,000 miles). Mind you, burning one quart every
1,500 miles is still considered "acceptable," but its still a bit
annoying nevertheless. So, on the advice of a Ford tech, at 65,000
miles, I switched over to synthetic (specifically, Mobil 1 10W-30). The
oil consumption almost completely stopped, and the engine has
experienced no adverse effects whatsoever from making the switch
(contrary to what others may tell you they've experienced). I concluded
that the higher flashpoint (temperature at which oil burns) of synthetic
oil effectively prevented it from burning off.

If you do not find another cause of your increasing oil consumption, you
may (or may not) wish to try switching to synthetic oil. Be advised that
many people would likely recommend against it, however, since its
superior lubricating qualities have been reported to create a variety of
problems (including oil leakage) when used in engines that are
well-broken-in. Some people will probably even tell you that switching
to synthetic might increase, instead of decrease, your rate of oil
consumption. All I know is that it did not have that effect in my '89
5.0L, which now has over 90,000 miles on it and burns less than 1/2
quart of oil between changes every 3,000 miles.

--
Michael Clark
San Jose, California
1996 SVT Cobra Convertible #693/2510
(Crystal White/White/Saddle Tan)
1993-1/3 5.0L LX "Feature Car" Convertible
(Canary/White/White)
SCOA
MCA

Mike Burress

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Mar 17, 1997, 3:00:00 AM3/17/97
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Jonathan Dlouhy <dlo...@mindspring.com> wrote in article
<332a4bc5...@news.mindspring.com>...
> Sorry if this topic has already been covered. I've got a 1991 5.0

> coupe with 80,000 miles that's started burning oil at the rate of 1
> quart per 2000 miles. Is this normal for these engines? If so, any

> guesses as to the rate at which this situation will get worse?
>
> Thanks,
> Jonathan Dlouhy
> Principal Oboe, A.S.O.
> dlo...@mindspring.com
> Evolution is God's way of issuing upgrades
>

Jonathon-

My wife's 88 GT has 166k miles on it and burns a quart about
every 2k miles. I replaced the valve seals at 120k miles which
helped some. Now, the rear main seal has started weeping
so that's the next thing to fix. The car has always used a quart
every 2k miles; I think this is somewhat normal for these cars.
You may need to run some engine deposit remover (Ford sells
some excellent remover, BTW) if you experience significant
engine deposits (engine pings even with good gas).

Mike


RONERSGT

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Mar 17, 1997, 3:00:00 AM3/17/97
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Be sure of another thing. Make sure there's no oil AT ALL WHATSOEVER in
the coolant. IF ( I SAY IF ) there is, then your head gaskets are bad.
Oil would seep into the coolant system that way.

Bill Kiene

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Mar 17, 1997, 3:00:00 AM3/17/97
to

On Sat, 15 Mar 1997 07:15:02 GMT, dlo...@mindspring.com (Jonathan Dlouhy) wrote:

>Sorry if this topic has already been covered. I've got a 1991 5.0
>coupe with 80,000 miles that's started burning oil at the rate of 1
>quart per 2000 miles. Is this normal for these engines? If so, any
>guesses as to the rate at which this situation will get worse?
>
>Thanks,
>Jonathan Dlouhy
>Principal Oboe, A.S.O.
>dlo...@mindspring.com
>Evolution is God's way of issuing upgrades


If your car burns oil and you quite changing it because your always adding some
it can be very bad. Still change the oil every 3,000 to5,000 miles because if
you don't you will never get it clean. I think this is a common problem.


Bill Kiene
Kiene's Fly Shop
Sacramento,CA,USA
bki...@ns.net
800/4000FLY

Tom

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Mar 17, 1997, 3:00:00 AM3/17/97
to

On Sat, 15 Mar 1997 07:15:02 GMT, dlo...@mindspring.com (Jonathan
Dlouhy) wrote:
>Sorry if this topic has already been covered. I've got a 1991 5.0
>coupe with 80,000 miles that's started burning oil at the rate of 1
>quart per 2000 miles. Is this normal for these engines? If so, any
>guesses as to the rate at which this situation will get worse?
>
>Thanks,
>Jonathan Dlouhy
>Principal Oboe, A.S.O.
>dlo...@mindspring.com
>Evolution is God's way of issuing upgrades

My '87 burns about a quart every 1500-2000 miles (about one extra
quart between oil changes). I've changed the oil every 2000 miles
since it was new, and have 105K miles now. I don't worry about it,
since one of these days it's coming off the road for some major HP
parts. I'll have it rebuilt then. Until then, I just buy the cases
on sale!

Tom

Bruce Musgrove

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Mar 19, 1997, 3:00:00 AM3/19/97
to dlo...@mindspring.com

Jonathan Dlouhy wrote:
>
> Sorry if this topic has already been covered. I've got a 1991 5.0
> coupe with 80,000 miles that's started burning oil at the rate of 1
> quart per 2000 miles. Is this normal for these engines? If so, any
> guesses as to the rate at which this situation will get worse?
>
> Thanks,
> Jonathan Dlouhy
> Principal Oboe, A.S.O.
> dlo...@mindspring.com
> Evolution is God's way of issuing upgrades

Consider yourself lucky. Thats well below normal. Ford Spec say one
quart every 1 k is normal with the rings used in todays cars. Mine does
1 quart in 600, which the ford people still do not think is abnormal.
--
Bruce Musgrove
Bmu...@mednet.swmed.edu

Chris Shugg

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Mar 20, 1997, 3:00:00 AM3/20/97
to

> Consider yourself lucky. Thats well below normal. Ford Spec say one
> quart every 1 k is normal with the rings used in todays cars. Mine does
> 1 quart in 600, which the ford people still do not think is abnormal.
> --
> Bruce Musgrove
> Bmu...@mednet.swmed.edu


Call me odd man out, but the 5.0 in my 95 Cobra burns -zero- oil, or at
least none that you can see from checking the dipstick. I change the oil
every 3k, use Castrol Syntec, and the engine is just about to hit 40k
miles.

Chris

Pentium_Man

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Mar 22, 1997, 3:00:00 AM3/22/97
to

Chris Shugg <sh...@rtp.ericsson.se> wrote:

>> Consider yourself lucky. Thats well below normal. Ford Spec say one
>> quart every 1 k is normal with the rings used in todays cars. Mine does
>> 1 quart in 600, which the ford people still do not think is abnormal.
>> --
>> Bruce Musgrove
>> Bmu...@mednet.swmed.edu


A 1991 5.0 has forged pistons. It's normal for more oil blow-by pas the rings,
especially when the engine is cold..

A 1995 Cobra uses cast Hyper.... pistons. A much better fit, but not as strong
as forged pistons...

Dmustang58

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Mar 25, 1997, 3:00:00 AM3/25/97
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I have a problem....i too burn oil..it burns oil at a unknown rate.
when i accelerate hard i get a small puff of smoke when its not warmed
up...but it goes away, also my oil press is weak..i was considering
changing my oil pump and bearings....? what do you guys think? also the
heads are fresh...and i have the B303 CAM...and i hear more valve train
noise than before ..i dont think its that big of a change where i should
be getting all that noise

Donpavi...@yahoo.com

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May 27, 2017, 11:35:39 AM5/27/17
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How many miles on bottom end

Donpavi...@yahoo.com

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May 27, 2017, 11:37:00 AM5/27/17
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Cuz new heads on a weak bottom end do not mix well and bearings are gonna take the hit

joeli...@gmail.com

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May 27, 2017, 10:15:27 PM5/27/17
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Accordog to ford a quart every 950 miles us normal. Also whe driven hard, burning a little extra is normal.
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