Go Back  Offshoreonly.com > Technical > Do It Yourself, Boating on a Budget
Why I'm I losing oil pressure? 502 new engine >

Why I'm I losing oil pressure? 502 new engine

Notices

Why I'm I losing oil pressure? 502 new engine

Thread Tools
 
Old 07-23-2012 | 11:21 PM
  #1  
Thread Starter
Registered
 
Joined: Jul 2011
Posts: 126
Likes: 0
From: Pensacola FL
Default Why I'm I losing oil pressure? 502 new engine

Heres the deal.

Block, Crank and Rods 80hrs since new. and oil pump.

Just installed complete new bearings top to bottom.

New srp pistons and rings.

3" x 18" oil. Cooler and -12 oil fittings and lines.

Ran the engine 1.5hrs total time. 45 mins idle and 45 running no more than 4000k max. Most at 3500.

Ran 15 mins 3800 rpms. Backed off throttle and pressure went to 0

Idle. Cold 45
Idle warm 40

Cruise. 25-35
3800 had 40.

Running wix racing filter. Royal Purple 20-50 syn.

Engine temp 150-160
Oil temp never went over 195

Cut open the filter. Light silver dust. Seems light standard break in.

It does/ did have 11psi relief valve. Ordered 30 psi today.

Thanks OSO
YellowFever is offline  
Reply
Old 07-24-2012 | 12:09 AM
  #2  
Registered
 
Joined: Aug 2005
Posts: 6,306
Likes: 1
From: Between A Womans Leggs in IL
Default fixx

Originally Posted by YellowFever
Heres the deal.

Block, Crank and Rods 80hrs since new. and oil pump.

Just installed complete new bearings top to bottom.

New srp pistons and rings.

3" x 18" oil. Cooler and -12 oil fittings and lines.

Ran the engine 1.5hrs total time. 45 mins idle and 45 running no more than 4000k max. Most at 3500.

Ran 15 mins 3800 rpms. Backed off throttle and pressure went to 0

Idle. Cold 45
Idle warm 40

Cruise. 25-35
3800 had 40.

Running wix racing filter. Royal Purple 20-50 syn.

Engine temp 150-160
Oil temp never went over 195

Cut open the filter. Light silver dust. Seems light standard break in.

It does/ did have 11psi relief valve. Ordered 30 psi today.

Thanks OSO
just for ****s try another brand's filter..had a issue on a dirt track engine last weekend and we went from wix to a fram and picked up 30 psi of pressure..
FIXX is offline  
Reply
Old 07-24-2012 | 08:25 AM
  #3  
Full Force's Avatar
Gold Member
20 Year Member
Gold Member
 
Joined: Oct 2005
Posts: 11,691
Likes: 217
From: Olmsted Falls,Ohio Marblehead,Oh
Default

is it HV pump? if not it's not going to have much more then 45-50 and that is scary to me, but a lot of them run ok with that if the clearances are ok, but oil temps tell you everything..... so keep an eye on em..
Full Force is offline  
Reply
Old 07-24-2012 | 11:04 AM
  #4  
HiPerf2000's Avatar
Registered
 
Joined: Oct 2000
Posts: 4,082
Likes: 2
From: N.E.
Default

are you able to change that relief valve in the boat ?? i thought you had to thread a bolt and slap hammer them out, then press back in to install ??
HiPerf2000 is offline  
Reply
Old 07-24-2012 | 08:04 PM
  #5  
Thread Starter
Registered
 
Joined: Jul 2011
Posts: 126
Likes: 0
From: Pensacola FL
Default

Hiperf2000
Yes I changed it in the boat. Didn't improve the pressure.

Turns out the sender was getting oil behind the diaphragm and maxed the pressure at 40 psi. after a 20 min 3800 run. The sender was full behind the diaphragm. Then at idle, it's showed 0.

New sending unit 60 at idle cold. 55 warm.
2500rpms over 70psi.

Yea for me
YellowFever is offline  
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 On
Pingbacks are On
Refbacks are On



Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

Copyright © 2026 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.