Author Topic: Oil Pressure Fluctuation  (Read 7324 times)

Offline TxFiddler

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Oil Pressure Fluctuation
« on: August 09, 2010, 02:20:16 pm »
Well, I searched and couldn't find the same problem so here goes.  I noticed today that my oil pressure is going up and down.  1980 c10 2wd with 350.  When I'm at a stop with the truck in gear, the pressure drops close to zero.  I put it in neutral and the pressure comes back up to just under the half-way mark.  When driving the pressure is just under the half-way mark also.  The guage is stock.  I'm not sure of the age of the sending unit or oil pump.  Any suggestions?
80 C10 2wd / 427 BigBlock / 700R4 / 3:42 Eaton Posi LSD / 770 cfm Holley Street Avenger / Doug's Headers / MSD ProBillet Distributor / Champion 3 row Radiator

Offline Irish_Alley

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Re: Oil Pressure Fluctuation
« Reply #1 on: August 09, 2010, 03:35:48 pm »
I heard so dont qupte me on this but a bad pump can cause this if its about to fail
If you can’t tell yourself the truth, who can you tell it to?~Irish_Alley

When you have eliminated the impossible, whatever remains, however improbable, must be the truth ~Sherlock Holmes

Offline TxFiddler

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Re: Oil Pressure Fluctuation
« Reply #2 on: August 09, 2010, 03:38:00 pm »
I heard so dont qupte me on this but a bad pump can cause this if its about to fail

Well then it probably wouldn't be a bad idea to go ahead and get one.  Thanks!
80 C10 2wd / 427 BigBlock / 700R4 / 3:42 Eaton Posi LSD / 770 cfm Holley Street Avenger / Doug's Headers / MSD ProBillet Distributor / Champion 3 row Radiator

Offline Blazin

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Re: Oil Pressure Fluctuation
« Reply #3 on: August 09, 2010, 08:38:37 pm »
I would check the sending unit, and gage first. Allot less work!
Some people are like Slinkies. Not really good for anything, but they still bring a smile to your face when you push them down a flight of stairs

Offline TxFiddler

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Re: Oil Pressure Fluctuation
« Reply #4 on: August 09, 2010, 08:59:57 pm »
Blazin, thanks for the advice.  Since there aint no noise and the engine aint runnin hot, prolly not much to worry about. Right?  I need a day or so to get a new sending unit. (the bell shaped by the distributor, right?) 
80 C10 2wd / 427 BigBlock / 700R4 / 3:42 Eaton Posi LSD / 770 cfm Holley Street Avenger / Doug's Headers / MSD ProBillet Distributor / Champion 3 row Radiator

Offline Blazin

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Re: Oil Pressure Fluctuation
« Reply #5 on: August 09, 2010, 09:39:50 pm »
Yes.
Some people are like Slinkies. Not really good for anything, but they still bring a smile to your face when you push them down a flight of stairs

Offline heavychevy91

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Re: Oil Pressure Fluctuation
« Reply #6 on: August 09, 2010, 11:13:28 pm »
had the same problem with my truck. turned out to be a bad sending unit just as blazin said

Offline Irish_Alley

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Re: Oil Pressure Fluctuation
« Reply #7 on: August 10, 2010, 04:17:23 am »
yeah yeah yeah whatever lol  ::)no go with what they said i don't know why but that should of been the first thing that i said.
If you can’t tell yourself the truth, who can you tell it to?~Irish_Alley

When you have eliminated the impossible, whatever remains, however improbable, must be the truth ~Sherlock Holmes

Offline heavychevy91

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Re: Oil Pressure Fluctuation
« Reply #8 on: August 10, 2010, 09:30:53 am »
hey who knows i guess i was just hoping it wasnt a bad pump  ::)

Offline TxFiddler

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Re: Oil Pressure Fluctuation
« Reply #9 on: August 11, 2010, 02:07:49 pm »
Replaced the sending unit today and seems to have fixed the problem.  Oil guage reads around 12-15 at idle and 30+ when driving at highway speed.  Thanks for all the advice.  Now, what will be next?
80 C10 2wd / 427 BigBlock / 700R4 / 3:42 Eaton Posi LSD / 770 cfm Holley Street Avenger / Doug's Headers / MSD ProBillet Distributor / Champion 3 row Radiator

Offline topp

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Re: Oil Pressure Fluctuation
« Reply #10 on: August 11, 2010, 03:46:39 pm »
Now, what will be next?

Guage will go from all the electrons that are correctly flowing thru it... :D
'90 Suburban TBI 350

Offline bobcooter

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Re: Oil Pressure Fluctuation
« Reply #11 on: August 21, 2010, 06:26:55 am »
Replaced the sending unit today and seems to have fixed the problem.  Oil guage reads around 12-15 at idle and 30+ when driving at highway speed.  Thanks for all the advice.  Now, what will be next?
With my old rig I never ask what will be next. ;)
'79 C-20, 350/400, 3:73 gears, 9 leafs and a headache rack
Favorite Quote, "Good judgement comes from experience. Experience comes from poor judgement."