350 oil pressure - Pirate4x4.Com : 4x4 and Off-Road Forum

dkovac · 10-19-2001, 12:57 PM

when i start my K1500 up i get oil pressure at closer to 60 pounds then when driving at speed on the highway it drops to 40 pounds stopping at a red light etc drops it to 20 pounds
this just started to happen never noticed it this summer when i got the truck

normal or a problem brewing??

Thanks

D

The Rockslut · 10-19-2001, 03:06 PM

A good standard to go by is 10psi for every 1000rpm minimum Also the gauge can be going south Those pressures dont sound bad at all. If you are that concerned I would install a mechanical gauge and watch it.

4x4realm · 10-19-2001, 03:19 PM

My blazer the presure doesn't change that much but the truck I drive at work (93 3/4 ton 350 tbi) the presure seems to run about like what you discribed about 40 on freeway and 10-20 at a stop light. It's done that sents it was new.

dkovac · 10-19-2001, 04:41 PM

thanks guys

jakeoffroad · 10-25-2001, 10:06 PM

dude, i noticed my trash does about the same thing and i have an old school 350. i guess as the engine warms up the oil press drops. it still runs so i dont care <IMG SRC="smilies/usa.gif" border="0">

Black Dog · 10-26-2001, 06:21 AM

Those are good oil pressure readings. No problem whatsoever.

ranger · 10-26-2001, 08:29 AM

As long as you have positive oil pressure your good to go. Just remember when temps rise you oil viscosity breaks down, lowering operating pressures.

dkovac · 10-26-2001, 08:55 AM

I realize i will drop pressure as the oil warms up, thats why i am a little worried i never had this problem in the summer months with temps in the 90's
I just thought of a reason though
I did have one of the guys at work (i'm a car salesman) change the oil he could have put 5 weight oil in this would probably account for the pressure drop due to the thinner oil

ranger · 10-26-2001, 09:04 AM

Yep, if the dude put in a thinner oil in your truck it would cause your pressure to drop. <IMG SRC="smilies/skull.gif" border="0"> No worries!

coyote · 02-24-2003, 07:46 PM

So I've heard the 10 psi for every 1k rpms but when my system gets up to temp 180-190 my pressure drops to less then 10 (mech gauge) at idle and 650 rpm...it does climb quickly and I know that pressure and flow aren't the same and I have plugged the bypass to send the oil through the filter 100% and use 20w50....engine doesn't knock and have had the problem for awhile and haven't noticed any other problems....might try replacing the filter plate with the bypass unmolested....any ideas?????

Sidewalk · 02-24-2003, 11:02 PM

This is the spec for every engine I have worked on (except Harley

):

15 psi minimum at idle
45-60 psi at operating speed (2000 RPM for my BII)
75 psi max

This goes for my little VW, as well as the Fair-Banks Morse deisels that are the size of my house.

6869704x4 · 02-25-2003, 06:36 AM

If there is a change all of a sudden then something happened. The oiling system is actually more reliable than the indicating system. A cheap mechanical gauge is a good troubleshooting tool.

Here is some good info http://www.melling.com/support/bulletins/default.asp

10-19-2001, 12:57 PM	#1 (permalink)
dkovac Registered User Join Date: Jul 2000 Member # 1259 Location: Holland PA Posts: 8	350 oil pressure when i start my K1500 up i get oil pressure at closer to 60 pounds then when driving at speed on the highway it drops to 40 pounds stopping at a red light etc drops it to 20 pounds this just started to happen never noticed it this summer when i got the truck normal or a problem brewing?? Thanks D

10-19-2001, 03:06 PM	#2 (permalink)
The Rockslut Registered User Join Date: Jun 2001 Member # 5021 Location: Lincoln, CA Posts: 5,967	A good standard to go by is 10psi for every 1000rpm minimum Also the gauge can be going south Those pressures dont sound bad at all. If you are that concerned I would install a mechanical gauge and watch it. __________________ Don't be "THAT GUY" on the trail. www.voodoowax.com

10-19-2001, 03:19 PM	#3 (permalink)
4x4realm Registered User Join Date: May 2001 Member # 4737 Location: redding, ca Posts: 405	My blazer the presure doesn't change that much but the truck I drive at work (93 3/4 ton 350 tbi) the presure seems to run about like what you discribed about 40 on freeway and 10-20 at a stop light. It's done that sents it was new. __________________ 1989 Chevy Blazer 350 V8

10-25-2001, 10:06 PM	#5 (permalink)
jakeoffroad Registered User Join Date: Aug 2001 Member # 6287 Location: ft worth texas Posts: 25	dude, i noticed my trash does about the same thing and i have an old school 350. i guess as the engine warms up the oil press drops. it still runs so i dont care <IMG SRC="smilies/usa.gif" border="0"> __________________ have you taco'd a ten bolt lately? 83 chevy beast 37"boggers lock rights powered by white trash usmc will blow their shit up

10-26-2001, 06:21 AM	#6 (permalink)
Black Dog Registered User Join Date: Apr 2001 Member # 4140 Location: is everything Posts: 1,010	Those are good oil pressure readings. No problem whatsoever. __________________ Tim There is no accounting for taste 1936, 1937, 1943, 1950, 1952, 1954, 1955, 1997, 1998, 2002, [B][COLOR="Red"]2008[/COLOR][/B].

10-19-2001, 04:41 PM	#4 (permalink)
dkovac Registered User Join Date: Jul 2000 Member # 1259 Location: Holland PA Posts: 8	thanks guys

10-26-2001, 08:29 AM	#7 (permalink)
ranger Registered User Join Date: Jul 2000 Member # 1282 Location: Boise, Idaho Posts: 4,819	As long as you have positive oil pressure your good to go. Just remember when temps rise you oil viscosity breaks down, lowering operating pressures.

10-26-2001, 08:55 AM	#8 (permalink)
dkovac Registered User Join Date: Jul 2000 Member # 1259 Location: Holland PA Posts: 8	I realize i will drop pressure as the oil warms up, thats why i am a little worried i never had this problem in the summer months with temps in the 90's I just thought of a reason though I did have one of the guys at work (i'm a car salesman) change the oil he could have put 5 weight oil in this would probably account for the pressure drop due to the thinner oil

10-26-2001, 09:04 AM	#9 (permalink)
ranger Registered User Join Date: Jul 2000 Member # 1282 Location: Boise, Idaho Posts: 4,819	Yep, if the dude put in a thinner oil in your truck it would cause your pressure to drop. <IMG SRC="smilies/skull.gif" border="0"> No worries!

02-24-2003, 07:46 PM	#10 (permalink)
coyote Registered User Join Date: Feb 2000 Member # 170 Location: Phoenix, Az Posts: 2,532	So I've heard the 10 psi for every 1k rpms but when my system gets up to temp 180-190 my pressure drops to less then 10 (mech gauge) at idle and 650 rpm...it does climb quickly and I know that pressure and flow aren't the same and I have plugged the bypass to send the oil through the filter 100% and use 20w50....engine doesn't knock and have had the problem for awhile and haven't noticed any other problems....might try replacing the filter plate with the bypass unmolested....any ideas????? __________________ Red Racer I Toyota FJ62

02-24-2003, 11:02 PM	#11 (permalink)
Sidewalk Registered User Join Date: Sep 2001 Member # 7303 Location: Alameda, CA Posts: 132	This is the spec for every engine I have worked on (except Harley ): 15 psi minimum at idle 45-60 psi at operating speed (2000 RPM for my BII) 75 psi max This goes for my little VW, as well as the Fair-Banks Morse deisels that are the size of my house. __________________ All the same Buellshit to me. '04 Honda 1000RR - daily driver '59 VW - Long term toy '00 Buell X1 - #1,653 stunna '88 Ford Bronco II - Trail slut '00 Buell Blast - Power is not an option '04 Honda Shadow Aero - wife's daily driver '04 - Chrysler PT Cruiser - puppy transportation

02-25-2003, 06:36 AM	#12 (permalink)
6869704x4 Registered User Join Date: Oct 2002 Member # 14584 Location: The New and improved Mexico Posts: 467	If there is a change all of a sudden then something happened. The oiling system is actually more reliable than the indicating system. A cheap mechanical gauge is a good troubleshooting tool. Here is some good info http://www.melling.com/support/bulletins/default.asp __________________ Yes my truck is environmentally friendly. It lets most of the environment in the truck with you!

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