Cruisers Forum
 


Join CruisersForum Today

Reply
 
Thread Tools Rate Thread Display Modes
Old 04-02-2016, 22:13   #1
Registered User

Join Date: Jun 2013
Location: Antioch CA
Boat: Cal 39
Posts: 189
Black Fuel

I have a Perkins 4-108 in my 1971 Cal 39. The original engine was a Perkins 4-107. My fuel turns black after it has returned from the high pressure pump. It is obviously getting lubricating oil in it. Years ago when I was doing deliveries I had a boat where the oil level on the dipstick rose and there was lube oil in the fuel going to the injectors. A mechanic in Santa Cruz told me not to worry for the remainder of the delivery to Southern California because "a diesel engine can burn lube oil just fine."It is NOT diesel bugs or any other thing in the tanks. I have had the tanks scrubbed and the fuel polished. The boat has two fuel tanks. I put clean fuel in one tank and put the return fuel in the other. The clean tank stays clean. The "return" tank has black fuel. I'm not sure, but I think that lube oil is getting into the fuel in the high pressure pump, but having the pump rebuilt seemed to do nothing. The engine runs fine. It does not smoke (except upon startup for a few seconds). It's been this way for the last 8 years, including a couple Baja Bashes (and attempts of repair by mechanics in San Diego). Is there anbody on this forum that has had a similar problem? And how was it solved?
__________________

__________________
secrabtree is offline   Reply With Quote
Old 04-02-2016, 22:23   #2
Now on the Dark Side: Stink Potter.
 
CSY Man's Avatar

Cruisers Forum Supporter

Join Date: Aug 2003
Location: Ft. Lauderdale
Boat: 2001 Albin 28TE.
Posts: 3,398
Images: 115
Re: Black Fuel

If there is mixing of fuel and oil going on, have an oil sample tested to see if any fuel ends up in the crank case.
Had 6% fuel in the oil of my 4-108 but from a bad lift pump.
__________________

__________________
Life is sexually transmitted
www.odincharters.com
www.susanhanssen.com
CSY Man is offline   Reply With Quote
Old 06-02-2016, 07:21   #3
Registered User

Join Date: Jan 2008
Location: Med
Boat: Island Spirit 401 Catamaran
Posts: 313
Re: Black Fuel

I had a similar problem. The diaphragm pump on a Universal (Kubota) engine was sucking crank case oil into the fuel. The pump was located before the primary fuel filter which got fouled very quickly.

I had an inline electric backup fuel pump in place so I by-passed the mechanical pump and solved my problem until I could replace the mechanical. To stop the mechanical from simply pumping oil out of the crank case, i looped a hose from the intake to the output fittings on the pump.

Hope it is not your high pressure pump.
__________________
Ostinato is offline   Reply With Quote
Old 06-02-2016, 07:58   #4
Registered User

Join Date: Nov 2013
Location: Nice, France
Boat: Hunter Marine 38
Posts: 281
Re: Black Fuel

AFAIK the high pressure pump is lubricated by the diesel fuel only. Must be the diaphragm pump.
__________________
sailormed is offline   Reply With Quote
Reply

Tags
fuel

Thread Tools
Display Modes Rate This Thread
Rate This Thread:

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 Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Black Iron Fuel Tanks clarity36 Construction, Maintenance & Refit 40 01-08-2013 05:48
Black Taylor Made Fender Cover Turns Black from Sun ospreyman Product or Service Reviews & Evaluations 2 19-07-2011 10:38
Bloom Black Box Fuel Cell Ahnlaashock Electrical: Batteries, Generators & Solar 10 20-06-2010 13:43
BMW diesel and black steel diesel fuel tanks johnpair Engines and Propulsion Systems 12 08-01-2009 15:30



Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -7. The time now is 17:46.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.