Oil pressure problem.
Thread Starter
Racer
Joined: Feb 2000
Posts: 488
Likes: 28
From: Peabody MA
Oil pressure problem.
During one of my botched runs at New England Dragway tonight I had some spare time to actually look at the gauges. I noticed the the oil pressure gauge was wavering back and forth between 70 and 40 while in the 5500-6800 rpm range. I have a few things to check but would like some comments/opinions.
Also, I changed the oil today and the oil pressure at idle seems to be about 10 psi higher.
1. Add another quart just incase I'm pumping the pan dry. Most likely not the case.
2. Check the oil filter. Can these things be defective?
3. Pull, inspect, replace the oil pump.
If all else fails yank the motor.
As a side note I ran my best normally aspirated run. I also met a bunch of great Corvette Forum members!
R/T .451
60' 2.174
330 5.612
1/8 8.342
MPH 92.87
1000 10.661
1/4 12.593
MPH 118.81
As usual my 7 year old rock hard Dunlop SP8000's didn't hook too well. I think a set of drag radials in spring will be in order.
-Mike
Also, I changed the oil today and the oil pressure at idle seems to be about 10 psi higher.
1. Add another quart just incase I'm pumping the pan dry. Most likely not the case.
2. Check the oil filter. Can these things be defective?
3. Pull, inspect, replace the oil pump.
If all else fails yank the motor.
As a side note I ran my best normally aspirated run. I also met a bunch of great Corvette Forum members!
R/T .451
60' 2.174
330 5.612
1/8 8.342
MPH 92.87
1000 10.661
1/4 12.593
MPH 118.81
As usual my 7 year old rock hard Dunlop SP8000's didn't hook too well. I think a set of drag radials in spring will be in order.
-Mike
Team Owner
Joined: Sep 2001
Posts: 62,099
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From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
Re: Oil pressure problem. (Mike in Boston)
Oil pumps arent that expensive, you could just replace it.
Id be checking the sending unit too, but its also unlikely as a cause if it reads correctly at the normal-driving rpms.
Yes oil filters can be defective, but its a rare thing. (think FRAM)
Id be checking the sending unit too, but its also unlikely as a cause if it reads correctly at the normal-driving rpms.
Yes oil filters can be defective, but its a rare thing. (think FRAM)
Team Owner
Joined: Sep 2003
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From: Freedom is never more than one generation away from extinction.
St. Jude '03 thru '24
Re: Oil pressure problem. (Mike in Boston)
Have you considered running an accusump? Cheap insurance for expensive motors.
Autocrossers go in deeper, and come out harder....... :bb
Autocrossers go in deeper, and come out harder....... :bb
Thread Starter
Racer
Joined: Feb 2000
Posts: 488
Likes: 28
From: Peabody MA
Re: Oil pressure problem. (vader86)
I used a Fram PH30. When I picked my motor up from the engine builder it had an HP4 (HP somthing..) but I can't find them anywhere.
So should I use a stock oil pump, high pressure or high volume? It looks like people shy away from the high pressure. I think there's a high volume in there now.
-Mike
So should I use a stock oil pump, high pressure or high volume? It looks like people shy away from the high pressure. I think there's a high volume in there now.
-Mike
Team Owner
Joined: Mar 2000
Posts: 83,381
Likes: 87
From: Boston, MA
Re: Oil pressure problem. (Mike in Boston)
Mike, I use a Melling M55A pump which is a stock volume, high pressure pump. On my junkyard engine I was seeing 65psi @ 6000 with the oil temps in the 220* area. I have a K&N oil filter and Mobil 1 10W30 in it.
Great job on the ET, and that mph is just insane!!! I destroyed my clutch tonight, so I doubt I'll be racing next saturday. I've got some ET Streets with your name on them if you decide to go the 18th.
Great job on the ET, and that mph is just insane!!! I destroyed my clutch tonight, so I doubt I'll be racing next saturday. I've got some ET Streets with your name on them if you decide to go the 18th.
Thread Starter
Racer
Joined: Feb 2000
Posts: 488
Likes: 28
From: Peabody MA
Re: Oil pressure problem. (scorp508)
I destroyed my clutch tonight, so I doubt I'll be racing next saturday. I've got some ET Streets with your name on them if you decide to go the 18th.
Viva la yellow crap boxes!
Team Owner
Joined: Mar 2000
Posts: 83,381
Likes: 87
From: Boston, MA
Re: Oil pressure problem. (Mike in Boston)
Something tells me that if I bolted on a set of ET Streets I'd begin going through the "weak link" list rather quickly just like you did.
Viva la yellow crap boxes!
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Team Owner
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From: On a Wisconsin Death Trip
Re: Oil pressure problem. (scorp508)
Mike,
I conducted my own experiment after seeing 15lbs of oil pressure at idle while hot with a Fram. I switched to a Purolator filter - same oil - pressure at idle never drops below 25lbs now. Don't know if this is your problem but I think what I've read here and some other places is true: Fram is junk.
I was sucking the pan dry in a Mopar I had when I was younger. Overfilled it a quart and removed the windage tray and it was all good.
Hows' the single plane intake working for you? :seeya
I conducted my own experiment after seeing 15lbs of oil pressure at idle while hot with a Fram. I switched to a Purolator filter - same oil - pressure at idle never drops below 25lbs now. Don't know if this is your problem but I think what I've read here and some other places is true: Fram is junk.
I was sucking the pan dry in a Mopar I had when I was younger. Overfilled it a quart and removed the windage tray and it was all good.
Hows' the single plane intake working for you? :seeya
Pro
Joined: Apr 2003
Posts: 552
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From: Oz
Re: Oil pressure problem. (Mike in Boston)
I think there's a high volume in there now.
-Mike
-Mike
Thread Starter
Racer
Joined: Feb 2000
Posts: 488
Likes: 28
From: Peabody MA
Re: Oil pressure problem. (Mike in Boston)
Well, tomorrow I'll swap the oil filter for something other than a Fram and add an extra quart of oil. If that doesn't solve the issue I'll pick up a new oil pump for next weekends project.
Do the high pressure pumps make more pressure at idle or through out the entire RPM range? I'm seeing about 75 PSI in the upper RPMs with the high volume, I'm not sure if running any higher would be a problem?
The whole volume/pressure thing is still a little confusing.
Thanks for the comments guys.
-Mike
Do the high pressure pumps make more pressure at idle or through out the entire RPM range? I'm seeing about 75 PSI in the upper RPMs with the high volume, I'm not sure if running any higher would be a problem?
The whole volume/pressure thing is still a little confusing.
Thanks for the comments guys.
-Mike
Thread Starter
Racer
Joined: Feb 2000
Posts: 488
Likes: 28
From: Peabody MA
Re: Oil pressure problem. (loiq)
Hows' the single plane intake working for you?
I'm liking it better than my Miniram because the air flow distribition seems much better. All of my plugs are the same color whereas with the Miniram the rear plugs ran richer than the fronts.
It was a pain setting it up and getting it to fit under the hood but it I happy with it now. :D
You can see a few pics here http://mikeg73.home.comcast.net/Car/ProRam/ProRam.html
[Modified by Mike in Boston, 9:57 PM 10/12/2003]
