Varying Oil Pressure
11-07-2011, 05:12 PM
#1
Varying Oil Pressure The engine was running just fine for 1000 mis. It has a ported TR pump.
At 0 to 1000 mis, I had 40lbs cold, then 32 or so hot. It never did spike up upon acceleration.
I did the assembly, and know that the o-ring was seated correctly, originally.
Recently, after a WOT run, I started to hear some lifter clatter, and noticed that pressure dropped to 15-20 lbs...then to 6-8 lbs. I feathered the gas till I got back home. By this time pressure dropped to almost zero.
I thought that I might have a problem with gas diluting the oil, so the oil & filter were changed.
Today, it started up with 40lbs, & settled down to 32 hot idle.
On the way home, more lifter clatter, and pressure dropped to almost zero. I pulled over & shut it down. After a few minutes, started her up & got 22lbs. Giving it gas does not change the pressure.
The car will stay in the garage until this can be figured out.
Suggestions will be appreciated...thanks.
At 0 to 1000 mis, I had 40lbs cold, then 32 or so hot. It never did spike up upon acceleration.
I did the assembly, and know that the o-ring was seated correctly, originally.
Recently, after a WOT run, I started to hear some lifter clatter, and noticed that pressure dropped to 15-20 lbs...then to 6-8 lbs. I feathered the gas till I got back home. By this time pressure dropped to almost zero.
I thought that I might have a problem with gas diluting the oil, so the oil & filter were changed.
Today, it started up with 40lbs, & settled down to 32 hot idle.
On the way home, more lifter clatter, and pressure dropped to almost zero. I pulled over & shut it down. After a few minutes, started her up & got 22lbs. Giving it gas does not change the pressure.
The car will stay in the garage until this can be figured out.
Suggestions will be appreciated...thanks.
11-07-2011, 06:22 PM
#2
I thought that I might have a problem with gas diluting the oil, so the oil & filter were changed.
Today, it started up with 40lbs, & settled down to 32 hot idle.
On the way home, more lifter clatter, and pressure dropped to almost zero. I pulled over & shut it down. After a few minutes, started her up & got 22lbs. Giving it gas does not change the pressure.
The car will stay in the garage until this can be figured out.
Suggestions will be appreciated...thanks. .
Today, it started up with 40lbs, & settled down to 32 hot idle.
On the way home, more lifter clatter, and pressure dropped to almost zero. I pulled over & shut it down. After a few minutes, started her up & got 22lbs. Giving it gas does not change the pressure.
The car will stay in the garage until this can be figured out.
Suggestions will be appreciated...thanks. .
Do you know your gauge is working correctly? ... probably so if you're hearing the lifters make noise. But checking with a mechanical gauge is always a reassurance.
11-07-2011, 06:56 PM
#3
Even from the beginning, I noticed that the oil pressure did not always change 'proportionately' (or, evenly) to throttle response.
From previous experience with other engines, I recall oil pressure going up when throttle was increased, and oil pressure decreasing somewhat when feathering the gas or decelerating.
This engine never has behaved in that manner.
The lifter clatter was quite loud today...alarmingly so. This coincided with very low oil pressure readings on the gauge.
Can a pump leak internally?
Because the pressure returned to somewhat "normal" after restart, something has to be moving around within it.
I'm not looking forward to removing the damper, as it was a supertight fit.
From previous experience with other engines, I recall oil pressure going up when throttle was increased, and oil pressure decreasing somewhat when feathering the gas or decelerating.
This engine never has behaved in that manner.
The lifter clatter was quite loud today...alarmingly so. This coincided with very low oil pressure readings on the gauge.
Can a pump leak internally?
Because the pressure returned to somewhat "normal" after restart, something has to be moving around within it.
I'm not looking forward to removing the damper, as it was a supertight fit.
11-07-2011, 07:08 PM
#4
Sounds like a stuck pressure relief valve. I second running a mechanical gauge to be sure.
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11-07-2011, 07:26 PM
#5
I already am running an AutoGage mechanical gauge.
Looks like, at the least, the pump will have to come out/be replaced.
Going over all of the signs, I think that this pump has been acting up from day one. Not until recently did it begin to fail, though.
It could be worse...having to replace/reseat the dreaded o-ring!
Please continue to add your comments. Thanks.
Looks like, at the least, the pump will have to come out/be replaced.
Going over all of the signs, I think that this pump has been acting up from day one. Not until recently did it begin to fail, though.
It could be worse...having to replace/reseat the dreaded o-ring!
Please continue to add your comments. Thanks.
