Go Back  Offshoreonly.com > Technical > General Q & A
Twin 525s, different fuel consumption, is this normal? >

Twin 525s, different fuel consumption, is this normal?

Notices

Twin 525s, different fuel consumption, is this normal?

Thread Tools
 
Old 04-06-2015, 07:37 PM
  #1  
Registered
Thread Starter
 
Join Date: Jun 2011
Location: Guelph, Ontario, Canada
Posts: 136
Received 5 Likes on 4 Posts
Default Twin 525s, different fuel consumption, is this normal?

I bought a 2005 Fountain 35 with 525s last year (160 hrs on engines) and noticed starboard engine consistently burns 7% (stb tank takes more fuel at fill ups) more than port side. Boat ran great and both engines reach max rpm. Port engine drives hydraulic steering. Is this normal or should I be looking for a problem?
greg800le is offline  
Old 04-06-2015, 10:32 PM
  #2  
Registered
Platinum Member
iTrader: (3)
 
Join Date: May 2013
Location: Long Island, NY
Posts: 1,754
Likes: 0
Received 6 Likes on 6 Posts
Default

Had similar experience with my 38 with reverse stagger 525's. I don't think there was a problem but did notice slightly higher fuel consumption.
HyFive578 is offline  
Old 04-06-2015, 10:32 PM
  #3  
Registered
 
Join Date: Aug 2006
Posts: 71
Likes: 0
Received 1 Like on 1 Post
Default

A friend had a Gladiator did the same thing. He had it for about 5 years. It was the same from the day he bought it to the day he sold it. No problems, one just sucked more fuel. I think his was closer to 15% difference.
ondtip is offline  
Old 04-07-2015, 06:20 AM
  #4  
Registered
iTrader: (30)
 
Join Date: Dec 2004
Location: hampstead nh
Posts: 3,194
Likes: 0
Received 5 Likes on 5 Posts
Default

my cig is the same way ,,port motor always uses more ..always putting more fuel in port tank at fill up ..been that way since new 2003 38 gun
motors run perfect though ..checked everything several times scanned motors ect
smokin' gun is offline  
Old 04-07-2015, 02:51 PM
  #5  
Registered
 
Join Date: Jan 2005
Location: Katy, TX
Posts: 623
Received 15 Likes on 10 Posts
Default

And presume you 525 guys have many hours of dependable performance from your 525efi without major top end work or other? I know there are many threads on this, so just taking advantage here of a captive audience. I am a new 525 owner, I think 107 hours on mine. Just serviced out, all fluids, mech fuel pump, etc. Looking forward to my first summer with her. Got her in Aug 2015, storage about a month later...Started her twice during off season so far (that's winterization in Texas). Ha!
imartin is offline  
Old 04-07-2015, 03:17 PM
  #6  
Registered User
Gold Member
 
bcfountain's Avatar
 
Join Date: Apr 2007
Location: prince george,va
Posts: 1,474
Likes: 0
Received 0 Likes on 0 Posts
Default

my 10meter port motor uses about 8% more than my starboard.and there carbed motors and not injected.
bcfountain is offline  
Old 04-07-2015, 03:25 PM
  #7  
VIP Member
VIP Member
 
VoodooRob's Avatar
 
Join Date: Jul 2011
Location: Cleveland Ohio
Posts: 1,993
Received 46 Likes on 23 Posts
Default

Originally Posted by imartin
And presume you 525 guys have many hours of dependable performance from your 525efi without major top end work or other? I know there are many threads on this, so just taking advantage here of a captive audience. I am a new 525 owner, I think 107 hours on mine. Just serviced out, all fluids, mech fuel pump, etc. Looking forward to my first summer with her. Got her in Aug 2015, storage about a month later...Started her twice during off season so far (that's winterization in Texas). Ha!
Change the impellers and housings often, I do mine twice a year. The key with header longevity on these engines is keeping them as cool as possible at all times. Wouldn't be a bad idea to pressure check your headers and make sure the header bypass mod has been done.
VoodooRob is offline  
Old 04-07-2015, 03:39 PM
  #8  
Registered
 
Join Date: Jan 2005
Location: Katy, TX
Posts: 623
Received 15 Likes on 10 Posts
Default

Yes, new impellers were installed as well, fuel filter, new serp belt, everthing. Yes, the bypass mod was done too as part of the Merc recall. Can hold the headers as the boat idles and after a run. Thanks!

And to contribute to the thread, not just hijack it (LOL), Baja has a single tank so cant ascertain uneven fuel pull. I do have vessel view that can show fuel psi, etc per engine and wil look next time.

Last edited by imartin; 04-07-2015 at 03:47 PM.
imartin is offline  
Old 04-07-2015, 06:57 PM
  #9  
Registered
Thread Starter
 
Join Date: Jun 2011
Location: Guelph, Ontario, Canada
Posts: 136
Received 5 Likes on 4 Posts
Default

Good to hear 7% difference is not unusual. I bought the boat mid season and went through it changing all fluids, filters (including inline fuel filter) & mechanical pumps. Headers & impellers inspected, ecu scanned and all good. Ran great, even smoother at idle than my old 454 Mag MPI. It wasn't until the second fill up I noticed the starboard tank always needing more fuel. At the end of the season out of the 4 last fill ups I noticed the starboard tank took a total of 885 liters and the port took 828 liters (approx. 7% difference). I'm pulling it out of storage in a few weeks and want it 100% for this season. I now have 190 hrs. In addition to motor & drive oil, engine & water separator changed in fall, I'm changing the impellers, pulling the drives to check alignment & lube shifter cable / coupler drive spline etc. Please let me know if any other maintenance is recommended. Also, what is the "header bypass mod", and does the 2005 model year need it. I want my headers to last (after checking prices last year). Thx
greg800le is offline  

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