Go Back  Offshoreonly.com > Technical > General Q & A
496ho fuel problem >

496ho fuel problem

Notices

496ho fuel problem

Thread Tools
 
Old 06-24-2007, 04:35 PM
  #1  
Member #9
Charter Member
Thread Starter
 
hp500efi's Avatar
 
Join Date: Oct 2000
Location: Pewaukee, WI
Posts: 4,273
Likes: 0
Received 4 Likes on 2 Posts
Question 496ho fuel problem

Out boating today and docked. When leaving 1/2hr later, port motor no start. No big deal, limped back to launch and was just out checking motor. Pulled plugs....dry as a bone...pulled water seperator and it is full of gas, cycled fuel pump via the key while the hose was off of the water seperator and pump works and spits fuel. I DO NOT have factory inline fuel filters so I am wondering where do I go from here.

I did some searching here of other fuel related problems and my guess is I have a bad main pump or plugged somewhere. I did pull the cowling and pressed the schader valve on the fuel rail and I have fuel there (came squirting out).

The fuel cooler/pump looks extremely difficult to get at and remove.

How difficult is it to remove the injectors..any advice.

Thanks in advance!

Jeff
__________________
Member of the Liquid Jungle
hp500efi is offline  
Old 06-25-2007, 11:24 AM
  #2  
Registered
 
fountain27ho496's Avatar
 
Join Date: Jun 2002
Location: waterford,mi
Posts: 374
Likes: 0
Received 0 Likes on 0 Posts
Default

Pull the booster pump. Alum. 6" long behind seperator. Screen will be clogged with crap. 1 hr or less. Just did it again last week and it was packed. JC
fountain27ho496 is offline  
Old 06-25-2007, 12:08 PM
  #3  
Rough Seas Lie Ahead
Gold Member
 
Reckless32's Avatar
 
Join Date: Feb 2002
Location: Virginia Beach, VA
Posts: 2,465
Likes: 0
Received 0 Likes on 0 Posts
Default

Jeff, sent ya PM on cleaning the injectors.

To verify the boost pump thoroughly, you will need to do a pressure test on the fuel rail. Should be between 38-43 psi. I had one on each engine die last year within weeks of each other. When bad they will start in the mid 30 psi, then drop quick to around 20-25 making the motor run like crap and die. But you'll still get a little spurt of gas from the hose.

Pour your separator fuel into a jar or glass bowl and allow to sit for awhile, then check the fuel's condition if not already.

Clean the boost pump screen as suggested. Then clean the injectors as I described in the PM.

Start the engine and begin to feel around the exhaust manifolds to see that each cylinder is warming up (firing) nicely, otherwise a dead plug or wire.

The simple simon approach to the process of elimination is to keep in mind the three things a motor needs: Combustion/compression, fuel, and ignition.

Barring a sensor gone bad which you need a scantool to check, or and alrm (which typically fuel issues won't trigger) it's most likely fuel thanks to the Ethanol craze.

Good luck.
Reckless32 is offline  
Old 06-26-2007, 08:03 AM
  #4  
Gold Member
Gold Member
 
Rage's Avatar
 
Join Date: Sep 2005
Location: Missouri
Posts: 1,987
Likes: 0
Received 0 Likes on 0 Posts
Default

Sounds like a better fuel filter in the gas feed line is needed to catch the crap before it gets to the boost pump?
Rage is offline  
Old 06-26-2007, 09:15 AM
  #5  
Rough Seas Lie Ahead
Gold Member
 
Reckless32's Avatar
 
Join Date: Feb 2002
Location: Virginia Beach, VA
Posts: 2,465
Likes: 0
Received 0 Likes on 0 Posts
Default

The inline wasn't there in the first production models. it came later after some fuel issues.

Problem is they only catch the really large chunks of crap and pass the small stuff that can damage/clog the boost or injectors.

In the manual it says not to install any after market filters because the system is designed to flow properly on the current design? The main problem is the fuel doesn't hit another filter except a screen, until it already passes thru the fuel boost pump THEN to the separator.

You just have to keep an eye on the fuel's condition, and change spearators more frequently, and add additives such as Pri-G, StarTron, and Stabil.
Reckless32 is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
hp500efi
General Q & A
9
07-03-2007 11:08 AM
288sunny
General Q & A
47
02-26-2007 09:32 AM
tfarmer
Sonic
10
04-18-2006 09:58 PM
Rage
General Q & A
13
01-14-2006 05:53 AM
wms
General Q & A
6
06-14-2004 10:17 PM

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



Quick Reply: 496ho fuel problem


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

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.