10-08-2006, 06:37 AM
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Junior Member
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Join Date: Jan 2004
Posts: 10
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Low oil pressure - 2.0L Alfa Spider
Syptoms: Oil pressure is fine at start-up. After 3-5 minutes, it
drops to about 1/4 the normal pressure at road speeds (maintains
enough pressure at idle to keep the light off, but doesn't register
much on the gauge. The engine had a recent overhaul (probably <5000
miles ago).
Yep, dropped the pan(s). (What WERE they thinking when they designed
in some of those upper pan fixing bolts?)
Everything looks pretty good in there - popped off the main and rod
bearing caps I could get to (front half of the motor). A little wear
on one of the mains - nothing that I'd get excited about - a bit more
than typical in 5000 miles, but not much worse than that).
A couple questions for the experts...
1) What are the odds that the main / rod bearings I can't get to are
shot?
2) Is the symptom consistent with a worn-out oil pump, or does a bad
pump tend to "start low, stay low"?
3) Is there a source for a high-volume, high-pressure oil pump that
would improve the situation regardless of the cause?
Thanks,
Mark "contortionist" Hickey
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10-08-2006, 01:49 PM
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Junior Member
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Join Date: Oct 2006
Posts: 2
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Low oil pressure - 2.0L Alfa Spider
On Sun, 08 Oct 2006 07:37:36 -0700, Mark Hickey <mark@habcycles.com> wrote:
Quote:
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Syptoms: Oil pressure is fine at start-up. After 3-5 minutes, it drops to about 1/4 the normal pressure at road speeds (maintains enough pressure at idle to keep the light off, but doesn't register much on the gauge. The engine had a recent overhaul (probably <5000 miles ago). Yep, dropped the pan(s). (What WERE they thinking when they designed in some of those upper pan fixing bolts?) Everything looks pretty good in there - popped off the main and rod bearing caps I could get to (front half of the motor). A little wear on one of the mains - nothing that I'd get excited about - a bit more than typical in 5000 miles, but not much worse than that). A couple questions for the experts... 1) What are the odds that the main / rod bearings I can't get to are shot? 2) Is the symptom consistent with a worn-out oil pump, or does a bad pump tend to "start low, stay low"? 3) Is there a source for a high-volume, high-pressure oil pump that would improve the situation regardless of the cause? Thanks, Mark "contortionist" Hickey
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I would want to verify the numbers with a mechanical gauge before
assuming you have a problem. Also there are these oil gallery
plugs in the crank that can come adrift but you have full pressure
when cold so that does not exactly compute.
Bob
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10-09-2006, 02:22 AM
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Junior Member
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Join Date: Oct 2006
Posts: 1
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Low oil pressure - 2.0L Alfa Spider
"Mark Hickey" <mark@habcycles.com> wrote in message
news  kkgi21penb282s9hs99esbjap19557fdu@4ax.com...
Quote:
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Syptoms: Oil pressure is fine at start-up. After 3-5 minutes, it drops to about 1/4 the normal pressure at road speeds (maintains enough pressure at idle to keep the light off, but doesn't register much on the gauge. The engine had a recent overhaul (probably <5000 miles ago). Yep, dropped the pan(s). (What WERE they thinking when they designed in some of those upper pan fixing bolts?) Everything looks pretty good in there - popped off the main and rod bearing caps I could get to (front half of the motor). A little wear on one of the mains - nothing that I'd get excited about - a bit more than typical in 5000 miles, but not much worse than that). A couple questions for the experts... 1) What are the odds that the main / rod bearings I can't get to are shot? 2) Is the symptom consistent with a worn-out oil pump, or does a bad pump tend to "start low, stay low"? 3) Is there a source for a high-volume, high-pressure oil pump that would improve the situation regardless of the cause? Thanks, Mark "contortionist" Hickey
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Sorry not much of an expert on Alfa's BUT if it was a Classic Jaguar (which
I do know about) I would first check the sender and gauge!
Good Luke,
Peter
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10-09-2006, 03:18 AM
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Junior Member
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Join Date: Jan 2004
Posts: 10
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Low oil pressure - 2.0L Alfa Spider
"Peter" <peter.REMOVE.connell@REMOVE.brownsbox.com> wrote:
Quote:
"Mark Hickey" <mark@habcycles.com> wrote in messagenewskkgi21penb282s9hs99esbjap19557fdu@4ax .com...
Quote:
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Syptoms: Oil pressure is fine at start-up. After 3-5 minutes, it drops to about 1/4 the normal pressure at road speeds (maintains enough pressure at idle to keep the light off, but doesn't register much on the gauge. The engine had a recent overhaul (probably <5000 miles ago). Yep, dropped the pan(s). (What WERE they thinking when they designed in some of those upper pan fixing bolts?) Everything looks pretty good in there - popped off the main and rod bearing caps I could get to (front half of the motor). A little wear on one of the mains - nothing that I'd get excited about - a bit more than typical in 5000 miles, but not much worse than that). A couple questions for the experts... 1) What are the odds that the main / rod bearings I can't get to are shot? 2) Is the symptom consistent with a worn-out oil pump, or does a bad pump tend to "start low, stay low"? 3) Is there a source for a high-volume, high-pressure oil pump that would improve the situation regardless of the cause? Thanks, Mark "contortionist" Hickey
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Sorry not much of an expert on Alfa's BUT if it was a Classic Jaguar (whichI do know about) I would first check the sender and gauge!
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I replaced the sender (they have a history of creating the same
symptom) - no difference. I have pretty much ruled out the gauge
since I get a good reading when the engine's cold (and there's not
much chance that an electrical gauge would have symptoms that are
correlated with the temperature of the engine).
Mark Hickey
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10-09-2006, 03:43 AM
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Junior Member
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Join Date: Jun 2006
Posts: 47
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Low oil pressure - 2.0L Alfa Spider
Mark Hickey wrote:
Quote:
"Peter" <peter.REMOVE.connell@REMOVE.brownsbox.com> wrote:
Quote:
"Mark Hickey" <mark@habcycles.com> wrote in message newskkgi21penb282s9hs99esbjap19557fdu@4ax.com...
Quote:
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Syptoms: Oil pressure is fine at start-up. After 3-5 minutes, it drops to about 1/4 the normal pressure at road speeds (maintains enough pressure at idle to keep the light off, but doesn't register much on the gauge. The engine had a recent overhaul (probably <5000 miles ago). Yep, dropped the pan(s). (What WERE they thinking when they designed in some of those upper pan fixing bolts?) Everything looks pretty good in there - popped off the main and rod bearing caps I could get to (front half of the motor). A little wear on one of the mains - nothing that I'd get excited about - a bit more than typical in 5000 miles, but not much worse than that). A couple questions for the experts... 1) What are the odds that the main / rod bearings I can't get to are shot? 2) Is the symptom consistent with a worn-out oil pump, or does a bad pump tend to "start low, stay low"? 3) Is there a source for a high-volume, high-pressure oil pump that would improve the situation regardless of the cause? Thanks, Mark "contortionist" Hickey
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Sorry not much of an expert on Alfa's BUT if it was a Classic Jaguar (which I do know about) I would first check the sender and gauge!
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I replaced the sender (they have a history of creating the same symptom) - no difference. I have pretty much ruled out the gauge since I get a good reading when the engine's cold (and there's not much chance that an electrical gauge would have symptoms that are correlated with the temperature of the engine).
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If you gun the engine when hot, does the pressure gauge go up?
--
Catman MIB#14 SKoGA#6 TEAR#4 BOTAFOF#38 Apostle#21 COSOC#3
Tyger, Tyger Burning Bright (Remove rust to reply)
Alfa 116 Giulietta 3.0l (Really) Sprint 1.7 75 TS 156 TS S2
Triumph Speed Triple: Black with extra black bits
www.cuore-sportivo.co.uk
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10-09-2006, 07:20 AM
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Junior Member
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Join Date: Sep 2005
Posts: 71
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Low oil pressure - 2.0L Alfa Spider
"Mark Hickey" <mark@habcycles.com> schreef in bericht
news:vqbki2hvie8c9nk3hp1sm6kjvb1vq4gmq7@4ax.com...
Quote:
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I replaced the sender (they have a history of creating the same symptom) - no difference. I have pretty much ruled out the gauge since I get a good reading when the engine's cold (and there's not much chance that an electrical gauge would have symptoms that are correlated with the temperature of the engine). Mark Hickey
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Don't let Italian electrics fool you ;-(
Some one up this thread advised a mechanical pressure gauge.
I'll second that.
It won't be the first time the gauge it self has a condesor (resistor??)
that changes specification when in operation for a while (electric
resistance heats up the electrics of the guage resulting in changing
readings (only)........
--
Ciao from The Netherlands
alfistagj (aka Gert-Jan)
GT 2.0 JTS (2005)
Montreal 2.6V8 (1428700 - 1973/4)
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10-09-2006, 08:21 PM
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Junior Member
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Join Date: Jan 2004
Posts: 10
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Low oil pressure - 2.0L Alfa Spider
catman <catman@cuorerust-sportivo.co.uk> wrote:
Quote:
Mark Hickey wrote:
Quote:
"Peter" <peter.REMOVE.connell@REMOVE.brownsbox.com> wrote:
Quote:
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"Mark Hickey" <mark@habcycles.com> wrote
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> A couple questions for the experts...>> 1) What are the odds that the main / rod bearings I can't get to are> shot?>> 2) Is the symptom consistent with a worn-out oil pump, or does a bad> pump tend to "start low, stay low"?>> 3) Is there a source for a high-volume, high-pressure oil pump that> would improve the situation regardless of the cause?>> Thanks,> Mark "contortionist" Hickey Sorry not much of an expert on Alfa's BUT if it was a Classic Jaguar (which I do know about) I would first check the sender and gauge! I replaced the sender (they have a history of creating the same symptom) - no difference. I have pretty much ruled out the gauge since I get a good reading when the engine's cold (and there's not much chance that an electrical gauge would have symptoms that are correlated with the temperature of the engine).If you gun the engine when hot, does the pressure gauge go up?
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Yes, but not nearly as high as it should. The maximum pressure seems
to be about 15psi when the engine's fully warmed up - the decrease
from "normal" is gradual and thoroughly repeatable. At low RPM, the
needle isn't far off the left peg, though the low pressuer light never
even blinks on after the engine starts.
Mark Hickey
Habanero Cycles
http://www.habcycles.com
Home of the $795 ti frame
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10-09-2006, 09:42 PM
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Junior Member
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Join Date: Jun 2006
Posts: 47
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Low oil pressure - 2.0L Alfa Spider
Mark Hickey wrote:
<snip>
Quote:
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Yes, but not nearly as high as it should. The maximum pressure seems to be about 15psi when the engine's fully warmed up - the decrease from "normal" is gradual and thoroughly repeatable. At low RPM, the needle isn't far off the left peg, though the low pressuer light never even blinks on after the engine starts.
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What spec oil do you have in there?
--
Catman MIB#14 SKoGA#6 TEAR#4 BOTAFOF#38 Apostle#21 COSOC#3
Tyger, Tyger Burning Bright (Remove rust to reply)
Alfa 116 Giulietta 3.0l (Really) Sprint 1.7 75 TS 156 TS S2
Triumph Speed Triple: Black with extra black bits
www.cuore-sportivo.co.uk
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10-10-2006, 05:02 AM
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Junior Member
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Join Date: Jan 2004
Posts: 10
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Low oil pressure - 2.0L Alfa Spider
catman <catman@cuorerust-sportivo.co.uk> wrote:
Quote:
Mark Hickey wrote:<snip>
Quote:
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Yes, but not nearly as high as it should. The maximum pressure seems to be about 15psi when the engine's fully warmed up - the decrease from "normal" is gradual and thoroughly repeatable. At low RPM, the needle isn't far off the left peg, though the low pressuer light never even blinks on after the engine starts.
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What spec oil do you have in there?
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15-50 synthetic (Mobil 1) with an additive to boost the viscosity.
Mark Hickey
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10-10-2006, 06:36 AM
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Junior Member
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Join Date: Jun 2006
Posts: 47
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Low oil pressure - 2.0L Alfa Spider
Mark Hickey wrote:
Quote:
catman <catman@cuorerust-sportivo.co.uk> wrote:
Quote:
Mark Hickey wrote: <snip>
Quote:
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Yes, but not nearly as high as it should. The maximum pressure seems to be about 15psi when the engine's fully warmed up - the decrease from "normal" is gradual and thoroughly repeatable. At low RPM, the needle isn't far off the left peg, though the low pressuer light never even blinks on after the engine starts.
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What spec oil do you have in there?
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15-50 synthetic (Mobil 1) with an additive to boost the viscosity.
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Not that then. IIWY I'd try another gauge before any expensive
exploratory work.
--
Catman MIB#14 SKoGA#6 TEAR#4 BOTAFOF#38 Apostle#21 COSOC#3
Tyger, Tyger Burning Bright (Remove rust to reply)
Alfa 116 Giulietta 3.0l (Really) Sprint 1.7 75 TS 156 TS S2
Triumph Speed Triple: Black with extra black bits
www.cuore-sportivo.co.uk
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