Go Back  Offshoreonly.com > Technical > General Q & A
500EFI Overheat >

500EFI Overheat

Notices

500EFI Overheat

Thread Tools
 
Old 05-30-2018 | 11:02 AM
  #1  
Thread Starter
Registered
15 Year Member
 
Joined: Jun 2010
Posts: 4,806
Likes: 891
Default 500EFI Overheat

had an odd issue with starboard motor this past weekend. It would overheat at idle and cool down during cruise/WOT. Anyone ever have this issue? Where should I start?

some things I have ruled out by logic, let me know if you agree/dis-agree. Don’t think it’s a blockage because at cruise/wot the water pressure would spike and I would think flow go down and overheat. By that same logic I have kinda ruled out t stat.

Im thinking it’s an impeller issue or leak maybe in strainer cover pulling in air? The flow difference is noticeable when compared to port motor at idle.
1MOSES1 is offline  
Reply
Old 05-30-2018 | 03:11 PM
  #2  
cigrocket's Avatar
Registered
20 Year Member
 
Joined: Feb 2004
Posts: 2,590
Likes: 173
From: Endicott, NY
Default

Impeller is worn or housing. Not drawing enough when idle, when cruising water is being forced in and it will cool. Sometimes the slightest scratching or wear in the housing will cause 5-10 psi difference. Just my opinion. Should be easy fix. Buy kit and install. 1/2 hour job tops. Soap the impeller when installing
cigrocket is offline  
Reply
Old 05-30-2018 | 03:26 PM
  #3  
Thread Starter
Registered
15 Year Member
 
Joined: Jun 2010
Posts: 4,806
Likes: 891
Default

Originally Posted by cigrocket
Impeller is worn or housing. Not drawing enough when idle, when cruising water is being forced in and it will cool. Sometimes the slightest scratching or wear in the housing will cause 5-10 psi difference. Just my opinion. Should be easy fix. Buy kit and install. 1/2 hour job tops. Soap the impeller when installing
appreciate the feedback. Already have the kit on order. Will start there and report back.
1MOSES1 is offline  
Reply
Old 05-30-2018 | 03:40 PM
  #4  
F-2 Speedy's Avatar
Platinum Member
Community Builder
10 Year Member
Platinum Member
 
Joined: May 2012
Posts: 11,418
Likes: 3,938
From: Midwest & T-Rock
Default

Id order two.....spare one on the boat never hurts
F-2 Speedy is offline  
Reply
Old 05-30-2018 | 04:25 PM
  #5  
cigrocket's Avatar
Registered
20 Year Member
 
Joined: Feb 2004
Posts: 2,590
Likes: 173
From: Endicott, NY
Default

Originally Posted by F-2 Speedy
Id order two.....spare one on the boat never hurts
good call, I installed a brand new housing recently, it had a hairline crack in the boss cavity the way it was manufactured. Leaked and threw water all over the place when spinning faster then idle....lol. Good to have spares.
cigrocket is offline  
Reply
Old 06-01-2018 | 03:12 PM
  #6  
Thread Starter
Registered
15 Year Member
 
Joined: Jun 2010
Posts: 4,806
Likes: 891
Default

Pulled apart the pump. Everything looked good. We replaced it anyways. Haven’t had the chance to dunk it back in. We did notice that there are significant cracks in the sea strainer lid. See picture. Wondering if that could lead to pulling in air. Ordered a new lid already.
1MOSES1 is offline  
Reply
Old 06-01-2018 | 03:15 PM
  #7  
Thread Starter
Registered
15 Year Member
 
Joined: Jun 2010
Posts: 4,806
Likes: 891
Default

Attached
1MOSES1 is offline  
Reply
Old 06-01-2018 | 04:44 PM
  #8  
Registered
20 Year Member
 
Joined: Jan 2006
Posts: 3,598
Likes: 1,168
From: taxachusetts
Default

Originally Posted by 1MOSES1
Pulled apart the pump. Everything looked good. We replaced it anyways. Haven’t had the chance to dunk it back in. We did notice that there are significant cracks in the sea strainer lid. See picture. Wondering if that could lead to pulling in air. Ordered a new lid already.
switch lids,,see if it follows.good luck,hope it gets sorted out.
sutphen 30 is offline  
Reply
Old 06-01-2018 | 04:58 PM
  #9  
F-2 Speedy's Avatar
Platinum Member
Community Builder
10 Year Member
Platinum Member
 
Joined: May 2012
Posts: 11,418
Likes: 3,938
From: Midwest & T-Rock
Default

I had a similar issue with mine no cracks but the outer lip of the lid that holds the O-ring in place had deteriorated, I rebuilt them both
F-2 Speedy is offline  
Reply
Old 06-01-2018 | 10:41 PM
  #10  
Thread Starter
Registered
15 Year Member
 
Joined: Jun 2010
Posts: 4,806
Likes: 891
Default

1MOSES1 is offline  
Reply


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.