Oil pressure takes forever after oil change - Moparts Forums

Register Log In Moparts Forums Moparts Question and Answer Oil pressure takes forever after oil change

Print Thread

Page 1 of 2

1

2

Oil pressure takes forever after oil change #58237 05/11/08 02:50 PM 05/11/08 02:50 PM
A Anonymous OP Unregistered
Anonymous OP Unregistered A	Is it just me or this a common thing... everytime I do an oil change on the 400 it seems to take forever to get oil pressure. I had the truck run twice for about 30 seconds each time (after changing the oil) and I still have no pressure... I'd hate to run too long without knowing for sure...

Re: Oil pressure takes forever after oil change #58238 05/11/08 02:52 PM 05/11/08 02:52 PM
Joined: Nov 2007 Posts: 21,813 Kirkland, Washington Pacnorthcuda Too Many Posts
Pacnorthcuda Too Many Posts Joined: Nov 2007 Posts: 21,813 Kirkland, Washington	30 seconds!!!????? Yikes. First off are you priming your filter? Putting in as much oil as you can, waiting for it pass through the filter and keep adding till any more would be spillage as you put it on? If its really taking that long I would be thinking your pump is cavitating on air. Last edited by Pacnorthcuda; 05/11/08 02:53 PM.

Re: Oil pressure takes forever after oil change [Re: Pacnorthcuda] #58239 05/11/08 04:53 PM 05/11/08 04:53 PM
Joined: Jan 2003 Posts: 5,788 Hamilton, Ontario Canada Magnum master
Magnum master Joined: Jan 2003 Posts: 5,788 Hamilton, Ontario Canada	Did you actually time this? What is the pressure when it's warm and idling? I second prefilling the filter. I do that on everything. What grade of oil are you using? Truck 400's also have a pretty long suction tube. 69 Super Bee, 93 Mustang LX, 04 Allure Super

Re: Oil pressure takes forever after oil change [Re: Magnum] #58240 05/11/08 06:04 PM 05/11/08 06:04 PM
A Anonymous OP Unregistered
Anonymous OP Unregistered A	Yea I always fill my filters up as much as they'd take without spilling over (damn horizontal placement). I may prime it just to be on the safe side but sheesh a person shouldn't have to be doing this everytime they change the oil. I was using 20W50 but am now using Rotella 15W40. Pressure at warm idle is usually around 25. Startup is around 60-75 and driving is 40-50.

Re: Oil pressure takes forever after oil change #58241 05/11/08 06:10 PM 05/11/08 06:10 PM
Joined: Nov 2007 Posts: 21,813 Kirkland, Washington Pacnorthcuda Too Many Posts
Pacnorthcuda Too Many Posts Joined: Nov 2007 Posts: 21,813 Kirkland, Washington	If its REALLY taking that long (or even 10 seconds), I would be tempted to change the oil pump (they're cheap and easy) just to see if thats a fix. 30 seconds is about 10 times too long! At the least I would prime with a drill at each oil fill.

Re: Oil pressure takes forever after oil change #58242 05/11/08 06:13 PM 05/11/08 06:13 PM
Joined: Jan 2003 Posts: 8,064 Arlington, Texas earlybee master
earlybee master Joined: Jan 2003 Posts: 8,064 Arlington, Texas	Could be a sick oil pressure switch.

Re: Oil pressure takes forever after oil change [Re: earlybee] #58243 05/11/08 07:57 PM 05/11/08 07:57 PM
A Anonymous OP Unregistered
Anonymous OP Unregistered A	Well the prime did it... but at first it didn't want to with the oil filter on... once I took the filter off it came shooting out a couple seconds later... geez maybe i'm not filling the filter enough before i put it on... dunno... weird... anyhoo all is well now

Re: Oil pressure takes forever after oil change #58244 05/11/08 08:26 PM 05/11/08 08:26 PM
Joined: Mar 2003 Posts: 263 oregon daytonakid enthusiast
daytonakid enthusiast Joined: Mar 2003 Posts: 263 oregon	when oil pump gets worn they can do this. New pump should solve it. Bill

Re: Oil pressure takes forever after oil change #58245 05/11/08 09:33 PM 05/11/08 09:33 PM
Joined: Nov 2003 Posts: 2,715 closer to Canadian beer! torkrules I'm neurotic
torkrules I'm neurotic Joined: Nov 2003 Posts: 2,715 closer to Canadian beer!	Quote: Is it just me or this a common thing... everytime I do an oil change on the 400 it seems to take forever to get oil pressure. I had the truck run twice for about 30 seconds each time (after changing the oil) and I still have no pressure... I'd hate to run too long without knowing for sure... Sounds like it's loosing prime. My 496 did this once and while after an oil change and prolonged drain. So far the Hemi hasn't done this.

Re: Oil pressure takes forever after oil change [Re: torkrules] #58246 05/11/08 09:43 PM 05/11/08 09:43 PM
Joined: Jan 2003 Posts: 25,200 Upper Midwest M MoparforLife Too Many Posts
MoparforLife Too Many Posts M Joined: Jan 2003 Posts: 25,200 Upper Midwest	Are you checking with a manual gauge or the electric OEM gauge. If manual gauge it may take a short time longer if you line is very small. The line that I installed the last time had a smaller inside diameter than the old line I replaced and it took longer for the gauge to read pressure and to build up. You more than likely have pressure to the bottom end right away. It will take slightly longer to get to the top and to the gauge. If your lifters aren't rattling I wouldn't worry about it.

Re: Oil pressure takes forever after oil change [Re: MoparforLife] #58247 05/11/08 10:09 PM 05/11/08 10:09 PM
A Anonymous OP Unregistered
Anonymous OP Unregistered A	All my gauges are Autometer and the oil is electric. The pump itself is a new MP unit with barely 800 miles on it. Maybe it is losing its prime... is it possible that the setup on the B/RBs can be prone to "air lock"? I wouldn't think but just curious...

Re: Oil pressure takes forever after oil change #58248 05/11/08 10:15 PM 05/11/08 10:15 PM
Joined: Nov 2007 Posts: 21,813 Kirkland, Washington Pacnorthcuda Too Many Posts
Pacnorthcuda Too Many Posts Joined: Nov 2007 Posts: 21,813 Kirkland, Washington	Even if the pickup tube is completey draining itself during the oil change the oil pump should re-prime itself within a couple seconds of startup (these are positive displacement pumps, a vacuum will be drawn immediately IF they are working corectly.) I would disassemble the pump and inspect. OR try a different gauge ....one or the other.

Re: Oil pressure takes forever after oil change [Re: Pacnorthcuda] #58249 05/11/08 10:55 PM 05/11/08 10:55 PM
Joined: Feb 2003 Posts: 21,318 Manitoba, Canada DaytonaTurbo Too Many Posts
DaytonaTurbo Too Many Posts Joined: Feb 2003 Posts: 21,318 Manitoba, Canada	Any particular reason why you are running 20-50 or 15-40? Seems unnecessarily thick to me(for average Canadian temps). I've got an unopened, unknown mileage 440 and I run 10-30 in it. Oil pressure is the exact same as with the 15-40 which I have tried but no longer bother with. I don't fill the filter either, nor do I prime it, and after an oil change it only takes maybe 2 seconds or so before the needle in my cheapie mechanical oil pressure gauge shoots up to 76psi - the normal cold oil pressure reading for it. I would try a different gauge, throw on a cheapie mechanical gauge before next time, just incase it's somehow a gauge/sender issue. Either that or try a thinner oil.

Re: Oil pressure takes forever after oil change [Re: DaytonaTurbo] #58250 05/12/08 12:00 AM 05/12/08 12:00 AM
Joined: Jan 2008 Posts: 350 CT USA N Nick Mineau enthusiast
Nick Mineau enthusiast N Joined: Jan 2008 Posts: 350 CT USA	i have noticed my 440 takes a 1-3 seconds @ idle. but it seems if you bring it right to 1100 rpms its almost instant. i dont know which way is better though.

Re: Oil pressure takes forever after oil change [Re: DaytonaTurbo] #58251 05/12/08 06:21 AM 05/12/08 06:21 AM
A Anonymous OP Unregistered
Anonymous OP Unregistered A	Quote: Any particular reason why you are running 20-50 or 15-40? Seems unnecessarily thick to me(for average Canadian temps). I've got an unopened, unknown mileage 440 and I run 10-30 in it. Oil pressure is the exact same as with the 15-40 which I have tried but no longer bother with. I don't fill the filter either, nor do I prime it, and after an oil change it only takes maybe 2 seconds or so before the needle in my cheapie mechanical oil pressure gauge shoots up to 76psi - the normal cold oil pressure reading for it. I would try a different gauge, throw on a cheapie mechanical gauge before next time, just incase it's somehow a gauge/sender issue. Either that or try a thinner oil. Well I read from various service books that the original specs on these engines called for a 20w50 so when I first got into these I just went with what was stated... However I have been wondering of late why such a thick oil is needed hence the drop to Rotella 15w40.

Re: Oil pressure takes forever after oil change #58252 05/12/08 07:32 AM 05/12/08 07:32 AM
Joined: Jan 2003 Posts: 25,200 Upper Midwest M MoparforLife Too Many Posts
MoparforLife Too Many Posts M Joined: Jan 2003 Posts: 25,200 Upper Midwest	Quote: Well I read from various service books that the original specs on these engines called for a 20w50 so when I first got into these I just went with what was stated... However I have been wondering of late why such a thick oil is needed hence the drop to Rotella 15w40. NEVER seen a manual that OEM stated to use 20/50 oil. Most of the time they specified 10/30. Yes big blocks do air lock at times. Have had it happen but it is not all that common.

Re: Oil pressure takes forever after oil change [Re: MoparforLife] #58253 05/12/08 09:08 AM 05/12/08 09:08 AM
A Anonymous OP Unregistered
Anonymous OP Unregistered A	Haynes Manual I have here that covers the last couple years of big block Dodge trucks shows 20w50?

Re: Oil pressure takes forever after oil change #58254 05/12/08 09:11 AM 05/12/08 09:11 AM
Joined: Jan 2003 Posts: 18,406 UPPER MICHIGAN, MARQUETTE COUN... N NITROUSN I Live Here
NITROUSN I Live Here N Joined: Jan 2003 Posts: 18,406 UPPER MICHIGAN, MARQUETTE COUN...	Quote: Haynes Manual I have here that covers the last couple years of big block Dodge trucks shows 20w50? Thats bull crap. A Haynes manual is junk and full of mis information.

Re: Oil pressure takes forever after oil change [Re: MoparforLife] #58255 05/12/08 09:11 AM 05/12/08 09:11 AM
Joined: Jul 2005 Posts: 1,181 Lost in the ozone again S stubbs300 Vacation
stubbs300 Vacation S Joined: Jul 2005 Posts: 1,181 Lost in the ozone again	You say that you prime the filter, GOOD! Try this next time, fill the filter as full as possible and let it sit while you drain the old. Look at the filter and top it off as oil will soak into all that paper and stuff. It like a double prime of the filter and should cut your dry time some more. Good Luck

Re: Oil pressure takes forever after oil change [Re: NITROUSN] #58256 05/12/08 09:22 AM 05/12/08 09:22 AM
Joined: Nov 2004 Posts: 7,274 s.w.fl B bonefish master
bonefish master B Joined: Nov 2004 Posts: 7,274 s.w.fl	Quote: Quote: Haynes Manual I have here that covers the last couple years of big block Dodge trucks shows 20w50? Thats bull crap. A Haynes manual is junk and full of mis information. you ever notice how the haynes manuals are made of real cheap paper? thats so you can wipe with them.

Page 1 of 2

1

2

Moderated by Al_Alguire, Hotwheelsjr, moparts, not_a_charger, RangerDan440, tboomer

Hop To

Powered by UBB.threads™ PHP Forum Software 7.7.1