Go Back  Offshoreonly.com > Technical > General Q & A
496HO Not Spinning up... >

496HO Not Spinning up...

Notices

496HO Not Spinning up...

Old 04-18-2007, 02:04 PM
  #1  
Rough Seas Lie Ahead
Gold Member
Thread Starter
 
Reckless32's Avatar
 
Join Date: Feb 2002
Location: Virginia Beach, VA
Posts: 2,465
Likes: 0
Received 0 Likes on 0 Posts
Default 496HO Not Spinning up...

Took mine for a quick lap last weekend, and I found my starboard engine not wanting to do it's fair share getting up onplan or running. Pushing wide open the stbd only spun up to approx. 3500 rpm while the other was doing all the work and working hard at 4500. Starts/idles fine and no alarms not does it act like the guardian kicking in.

Any thoughts?

I'm gonna check the fuel pressure first, pull the fuel separators and check the fuel condition (had a bad gas problem last summer thanks to Ethanol) then pull a couple of plugs to see what shape they're in (215 hours).
Reckless32 is offline  
Old 04-18-2007, 02:13 PM
  #2  
Gold Member
Gold Member
 
Dave M's Avatar
 
Join Date: Oct 2000
Location: Hollywood, MD, USA
Posts: 5,652
Received 122 Likes on 77 Posts
Default

I'd start by connecting it to a scan tool.
Dave M is offline  
Old 04-18-2007, 02:25 PM
  #3  
Registered
 
Knot 4 Me's Avatar
 
Join Date: Jun 2005
Location: Central IL
Posts: 8,360
Received 742 Likes on 400 Posts
Default

Make sure you didn't have any plug wires come off.
Knot 4 Me is offline  
Old 04-19-2007, 03:34 PM
  #4  
Rough Seas Lie Ahead
Gold Member
Thread Starter
 
Reckless32's Avatar
 
Join Date: Feb 2002
Location: Virginia Beach, VA
Posts: 2,465
Likes: 0
Received 0 Likes on 0 Posts
Default

I went thru a fuel/ethanol problem last year and had to replace both boost pumps, and numerous separators before it started running fine. Also had it scanned and it read out fine. Now it sat over the winter and now this.

I'm hoping after doing the stupid-simple stuff mentioned above it'll be fine. If not, then I'll have another go-around on the scanner.
Reckless32 is offline  
Old 04-19-2007, 06:40 PM
  #5  
Registered
 
H2Xmark's Avatar
 
Join Date: Apr 2001
Location: beaumont tx
Posts: 1,703
Likes: 0
Received 0 Likes on 0 Posts
Default

if its left over winter fuel you are running change the filters and add some fresh fuel to it
H2Xmark is offline  
Old 04-19-2007, 09:36 PM
  #6  
Registered
 
Join Date: Jan 2005
Location: Hampton Falls ,NH
Posts: 67
Likes: 0
Received 0 Likes on 0 Posts
Default

Have experienced issues with the injectors, there is a very fine screen at the top of the injector, they clog. This paticular boat was an older one repowered with a 496. The ethanol loosened up sediment in the tank it went through all filters and to the injectors. No codes found & had perfect fuel pressure, removed injectors, blew the screens out and it ran fine.
Old Ride is offline  
Old 04-19-2007, 09:46 PM
  #7  
Registered
 
Join Date: Jul 2005
Location: evansville In
Posts: 482
Likes: 0
Received 0 Likes on 0 Posts
Default

Just had a similar prob. on a 496. Make sure all cyl. are firing! Simple test if you can get to the bottom of your exhaust manifolds, Touch each one before it is warmed up and you might find one of them colder than the rest.I scanned the injectors,everyone passed...ohmed every injector,all passed...Cut each cyl. one by one and #4 was it....swapped #2 and #4 injector and then #2 was not firing! But every scan tool test said it was working fine..
speedreeder is offline  
Old 04-20-2007, 09:50 AM
  #8  
Rough Seas Lie Ahead
Gold Member
Thread Starter
 
Reckless32's Avatar
 
Join Date: Feb 2002
Location: Virginia Beach, VA
Posts: 2,465
Likes: 0
Received 0 Likes on 0 Posts
Default

Well I'm basically hoping this ios my issue. Early january I fired it up to flush again, circulate the oil, and charge batteries while on my lift. I had took the practically empoty approach to winterization. I went thru roughly 10-12 separators last season to clean out my tank in my 2005 boat. The last spearator change showed good clean fuel when poured into a jar.

Anyway, while running it the one motor died and I'm assunming it ran out of gas. I rpomptlt went and got a five gallon can of fuel, mixed all the potions avaialble off the shelf, and put it in. I then fired it back up. I noticed it started idling crappy and decided to check it again later. Now it's later. I'm hoping when it ran dry, it in fact clogged up the separator maybe with some remianing bottom garbage from last season since it was well settled by then from lack of movement.

In the meantime I will use your tips for checking the injectors once all else fails.

Speedreeder once you found your issue, what was you fix? New injector harness? If so how much?
Reckless32 is offline  
Old 04-20-2007, 10:37 AM
  #9  
Registered
 
Dave_N's Avatar
 
Join Date: Jan 2005
Location: Newport Beach,CA
Posts: 573
Likes: 0
Received 1 Like on 1 Post
Default

Given the fuel issues that you have had, checking/replacing the injector screens is an excellent idea.

Dave
Dave_N is offline  
Old 04-21-2007, 08:53 AM
  #10  
Rough Seas Lie Ahead
Gold Member
Thread Starter
 
Reckless32's Avatar
 
Join Date: Feb 2002
Location: Virginia Beach, VA
Posts: 2,465
Likes: 0
Received 0 Likes on 0 Posts
Default

Sounds good to me to check regardless. So what's the basic 101 backyard mech approach to accessing the screens and blowing them out?
Reckless32 is offline  

Quick Reply: 496HO Not Spinning up...


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.