Hemi oil pressure

Reply

  #1  
Old 08-22-09, 04:47 PM
Member
Thread Starter
Join Date: Jun 2008
Location: Eastern Georgia
Posts: 486
Received 0 Votes on 0 Posts
Hemi oil pressure

Alright Dodge guys its Hemi time!

I am working on a 2004 Dodge 1500 2 wheel drive with the 5.7 Hemi in it. Someone was working on it before me and could not solve the problem, so some of my info is second hand.

What I was told: The truck was running fine, then it was run low in oil, low enough to make the oil pressure gauge bottom out, ane the engine to cut off. The oil and filter was changed, then you could drive the truck for a few miles before hearing the single tone to check gauges and the op gauge would be on the bottom, accompanied by the engine rattle. The oil pressure sending unit next to the oil filter was changed to try to fix this.

What I have seen for my self: When I first started working on the truck I ran it in the shop for about 20 minutes at varying engine speeds, then I drove it and sure enough within 2 miles I got the tone and 0 oil pressure reading on the gauge. I got out and listened to the engine, no bearing noise, but the lifters were very noisy. Drove back to the shop no oil pressure on gauge noisy lifters but no knocking. At the shop cut the truck off and restarted at once, oil gauge came up right away, lifters still noisy. A phone call confirmed that 20w50 oil had been put in at the change, I dropped this out and refilled with 5w30 as per owners manual. While under the truck I found the plug on the sending unit was not plugged on all the way, fixed that problem. Started truck, lifters quited down in about 45 seconds, proceded to drive truck for about 10 or 15 miles without incident.

Now the questions: Could the wrong oil have caused all that?
Is there another oil pressure sending unit that I have not found? Any one got any other ideas what might have caused this incident? Thanks in advance for any help, and I am sorry for the long post
 
Sponsored Links
  #2  
Old 08-22-09, 06:55 PM
Unclediezel's Avatar
Member
Join Date: Dec 2006
Location: Northeastern PA.
Posts: 2,230
Received 0 Votes on 0 Posts
Wrong oil?????ABSOLUTELY WILL CAUSE ALL OF THAT.

Just double check, I believe the correct oil as per MFR is 5w- 20..??? But I could be wrong.........

Lifters on the hemis are always Noisy......Nature of the beast....But a "Clatter" is not normal....

The kid at "Goofy Lube" was afraid of loosing his job, so he loosened the sender, in the hopes it would shut off the warning......But it didnt....
 
  #3  
Old 08-23-09, 12:02 PM
Member
Thread Starter
Join Date: Jun 2008
Location: Eastern Georgia
Posts: 486
Received 0 Votes on 0 Posts
Not the oil. If I run the engine hard on the road the oil pressure will drop, i can stop and shut down the engine, then restart it right away and the pressure will return. Do you think the pressure relief valve in the oil pump could be sticking?
 
  #4  
Old 08-24-09, 06:02 PM
Unclediezel's Avatar
Member
Join Date: Dec 2006
Location: Northeastern PA.
Posts: 2,230
Received 0 Votes on 0 Posts
A thought just occurred to me......

How much oil did you use to fill it?????

Hemis take 7 Quarts.......
 
  #5  
Old 08-24-09, 08:06 PM
Member
Thread Starter
Join Date: Jun 2008
Location: Eastern Georgia
Posts: 486
Received 0 Votes on 0 Posts
oil level is correct, I even looked under the truck to see if it was running out before I put in the last quart.
 
  #6  
Old 08-24-09, 11:27 PM
Member
Join Date: Jun 2009
Location: California
Posts: 214
Received 0 Votes on 0 Posts
OIl ?

From what you described I don't believe using 20/50 over 10/40 or any other combination would cause what you describe. I have a problem with a noisy top end as thats where a low pressure situation is usually first noted. It takes a lot more pressure to maintain a lifter function than oil shear at a bearing. I vote on the relief valve, do you have access to a dyno where it can be ran for a bit?
Bill
 
  #7  
Old 08-25-09, 05:29 AM
Member
Thread Starter
Join Date: Jun 2008
Location: Eastern Georgia
Posts: 486
Received 0 Votes on 0 Posts
No dyno, but it is driveable, I think it is the relief valve because when the pressure goes away the gauge does not just drop like an electrical fault, it kind of falls off gently like the pressure is bleeding off somewhere. All of this is academic now because the owner drove it yesterday, and came back with a very pronounced lower end (connecting rod) knock under load, even with full oil pressure, so looks like I need an engine now.
 
  #8  
Old 08-25-09, 06:46 AM
Member
Join Date: Jun 2009
Location: California
Posts: 214
Received 0 Votes on 0 Posts
Lower end

If you are skilled enough you could remove the pan and inspect the lower end bearings and mic the crank to verify the situation. Remove the rod caps and then the bearings, under the lower bearing insert an inspection will reveal what has happened as to damages and cause. We used to repair engines like that all the time ohhhhh many moons ago.
Bill
 
  #9  
Old 08-25-09, 02:27 PM
Member
Thread Starter
Join Date: Jun 2008
Location: Eastern Georgia
Posts: 486
Received 0 Votes on 0 Posts
All the bottom end parts, crank, rods, bearings, etc. are only available at factory prices. 600.00 for crank, 85.00 for rod bearings, 130.00 for main bearings, 200.00 for rod, 125.00 for oil pump. By the time I buy enough parts to fix it I can buy a used or reman engine.
 
  #10  
Old 08-25-09, 03:28 PM
Member
Join Date: Jun 2009
Location: California
Posts: 214
Received 0 Votes on 0 Posts
Prices

Didn't use to be so expensive for basic parts, it was the labor that cost.
Bill
 
  #11  
Old 08-25-09, 04:20 PM
Unclediezel's Avatar
Member
Join Date: Dec 2006
Location: Northeastern PA.
Posts: 2,230
Received 0 Votes on 0 Posts
Here is a situation that Boggles my mind......

Chrysler Corp makes you fight for every nickel of a warranty claim...
Waterpump is covered...gasket is not...Ball joints and tie rods are covered , but alignment is not.....Transmissions must be assessed at more than 70% of replacement cost, before I can request a reman unit.....

I remember as a Youngster in the business, replacing crankshafts, camshafts, replacing bearings, replacing pistons and rings......But now, an engine comes in with a knock, and its under warranty......

REMOVE AND REPLACE......We are not allowed to "Rebuild " engines.......I find this odd , being at a Chrysler Dealership, and fighting over 3 dollars for a water pump gasket, while the "CRATED ENGINES" are stacked up in MY BAY.....

As Im thinking..... I have seen Quite a Few "SLUDGING" issues on the Hemi's...2 in particular with the pick up screen packed solid..... If you get the opportunity to drop the oil pan....Check the pick up tube.......Running low on oil isnt exactly the same as Gasoline, where the sediment gets sucked off the bottom of the tank, But close......While the truck is running, The pan is almost empty anyway, since most of the Volume of oil is circulating, but any deviation from this "Running Level" can disrupt things quite a bit.....(Hence why I reminded you of the 7 quart oil capacity)

Jasper , ATK, and a host of others make Excellent options for replacements....Yeah .. I know its a Big Ticket...but anything that goes wrong is now SOMEONE ELSES HEADACHE..... Most of these companies offer a 3/36 warranty if not better....
 
  #12  
Old 08-25-09, 05:21 PM
Member
Thread Starter
Join Date: Jun 2008
Location: Eastern Georgia
Posts: 486
Received 0 Votes on 0 Posts
Thing that bothers me Unc, a person has to pay to transfer the powertrain warranty if they buy the vehicle used. Just another way to get out of paying for a covered repair.
 
  #13  
Old 08-25-09, 06:40 PM
Unclediezel's Avatar
Member
Join Date: Dec 2006
Location: Northeastern PA.
Posts: 2,230
Received 0 Votes on 0 Posts
Originally Posted by wire twister View Post
Thing that bothers me Unc, a person has to pay to transfer the powertrain warranty if they buy the vehicle used. Just another way to get out of paying for a covered repair.
Simply put, There is no way of knowing if the previous owner maintained it or not...Just cause' it has clean oil and a new air filter when you buy it, doesnt mean its always been treated that way.
The way around that, is if you buy a Trade in from a Dealership, they will usually be willing to absorb that cost into the price of the car, if you use THEIR service department for the repairs...Which of course you would, since its under warranty anyway...
Private owner is a bit tougher, but if it makes or breaks the deal...100$ can be "Sucked up".
 
Reply

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description: