Reply
 
Thread Tools Display Modes
 
Old 11-05-2013, 10:32 AM   #1
Guru
 
Dougcole's Avatar
 
City: Carrabelle, FL
Country: USA
Vessel Name: Morgan
Vessel Model: '05 Mainship 40T
Join Date: Jan 2008
Posts: 800
tracing mystery fuel leak

I have a small fuel leak that I can't find on my port motor, a 240hp yanmar, 4LHA stp.

After we crossed from Tarpon Springs to Carrabelle a few weeks back, I found approx. 2 oz of fuel on the diaper under the motor. The run took about 10 hours at 2,800 to 3,000 rpm, which is a little better than 15 knots.

I've been trying to find the leak, so far I have run the boat at idle up to 1,800 rpm, and there is nothing. I'm afraid to run the engine any faster than that without a load.

the fuel was all on the inboard side of the motor, under the injection pump. No spray at any of the injectors, no leak anywhere that I could find. I let it idle for 20 minutes, nothing.

Thoughts?

Thanks as always,
Doug
__________________
Advertisement

Dougcole is offline   Reply With Quote
Old 11-05-2013, 11:10 AM   #2
Guru
 
Xsbank's Avatar
 
City: Pender Harbour, BC
Country: Canada
Vessel Name: Gwaii Haanas
Vessel Model: Vancouver Shipyards Custom Aluminum 52
Join Date: Sep 2013
Posts: 2,447
I have used foot powder, the kind in an aerosol can, to trace leaks. Liquids leave tracks in it and it smells nice. Easy to clean up. And your engine won't get athlete's foot.
__________________

Xsbank is offline   Reply With Quote
Old 11-05-2013, 12:30 PM   #3
Guru
 
City: Pensacola
Country: USA
Join Date: May 2012
Posts: 748
Quote:
Originally Posted by Dougcole View Post
I have a small fuel leak that I can't find on my port motor, a 240hp yanmar, 4LHA stp.

After we crossed from Tarpon Springs to Carrabelle a few weeks back, I found approx. 2 oz of fuel on the diaper under the motor. The run took about 10 hours at 2,800 to 3,000 rpm, which is a little better than 15 knots.

I've been trying to find the leak, so far I have run the boat at idle up to 1,800 rpm, and there is nothing. I'm afraid to run the engine any faster than that without a load.

the fuel was all on the inboard side of the motor, under the injection pump. No spray at any of the injectors, no leak anywhere that I could find. I let it idle for 20 minutes, nothing.

Thoughts?

Thanks as always,
Doug
I would look at the fuel injector pump. There is a habit of vibration working the banjo fitting loose. Mine was only seen when engine was running.
Blue Heron is offline   Reply With Quote
Old 11-05-2013, 11:11 PM   #4
Guru
 
C lectric's Avatar
 
City: Somewhere
Country: , Canada
Vessel Name: Island Pride
Vessel Model: Palmer sedan 32'
Join Date: Oct 2007
Posts: 1,868
I've used the blue Scott paper towels for leak chasing. There is distinct colour change if something wet touches it which a white towel cannot do.

i ike the foot or talcum powder. I may try that next time to boot.
C lectric is offline   Reply With Quote
Old 11-06-2013, 06:22 AM   #5
FF
Guru
 
FF's Avatar
 
Join Date: Oct 2007
Posts: 16,524
In FLA boat fuel is red died, off road (no road taxes) and white paper toweling works.
FF is offline   Reply With Quote
Old 11-06-2013, 06:52 AM   #6
Scraping Paint
 
City: Fort Lauderdale
Vessel Model: CHB 48 Zodiac YL 4.2
Join Date: Oct 2007
Posts: 3,804
Most diesel fuel flouresces to some degree. Use one of those little UV LED flashlights in subdued lighting and you may be able to track down the leak.

If your fuel doesn't glow in the dark or if you want to check the whole system quickly, add a couple of ounces of tracer dye to your tanks, and a different color dye to the coolant system. It doesn't take much to pinpoint even the smallest leak.
__________________

RickB is offline   Reply With Quote
Reply

Thread Tools
Display Modes

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





All times are GMT -5. The time now is 03:58 PM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2006 - 2012