Cruisers Forum
 


Join CruisersForum Today

Reply
 
Thread Tools Rate Thread Display Modes
Old 21-09-2013, 09:20   #1
Registered User
 
CoCoKnots's Avatar

Join Date: Jul 2011
Location: Colorado/CoCoa Beach
Boat: Irwin 42
Posts: 61
perkins 4-108 stalls at idle

I have a 1975 Perkins 4-108. This is my first Diesel engine... Please excuse me as this is unfamiliar territory. I had the injectors & alternator rebuilt 3 years ago. Replaced the starter a couple of months ago, which probably has nothing to do with my stalling issue... It starts fine & runs under load. It just stalls when I return to idle to change gears.
I have replaced the Racor filters, but the problem still persist. It's been a couple of years since I've changed the primary fuel filter on the engine. I do use fuel additive. I haven't used the boat very much at all during that time.

Could the primary filter be the cause of the stalling problem?... Or is this an indicator of a more involved problem.

I hate changing the primary filter. A mechanic told me of a screw-on upgrade available to replace the sandwich type currently located on the block. Does anyone have feedback or experience with the aftermarket filter bracket?
__________________

__________________
CoCoKnots is offline   Reply With Quote
Old 21-09-2013, 09:54   #2
Registered User

Join Date: May 2008
Location: daytona beach florida
Boat: csy 37
Posts: 2,844
Images: 1
Re: perkins 4-108 stalls at idle

yes, the primary is a pain in the butt, butt it has to be done. go thou and do it..
__________________

__________________
onestepcsy37 is offline   Reply With Quote
Old 21-09-2013, 10:49   #3
Registered User
 
CoCoKnots's Avatar

Join Date: Jul 2011
Location: Colorado/CoCoa Beach
Boat: Irwin 42
Posts: 61
Re: perkins 4-108 stalls at idle

Thanks OneStepCSY37
Are you (or anyone) familiar with the screw on mount modification ?
__________________
CoCoKnots is offline   Reply With Quote
Old 21-09-2013, 18:07   #4
Registered User
 
capttman's Avatar

Join Date: Apr 2011
Location: Satellite Beach Florida
Boat: Bruce Roberts 434
Posts: 716
Send a message via Skype™ to capttman
Us your idle low
__________________
Capttman

"When the bow be in the trees we'll be running out of seas"
capttman is offline   Reply With Quote
Old 21-09-2013, 18:13   #5
Registered User
 
CoCoKnots's Avatar

Join Date: Jul 2011
Location: Colorado/CoCoa Beach
Boat: Irwin 42
Posts: 61
Re: perkins 4-108 stalls at idle

Yes it is Capttman,
But the throttle lags all the way as I advance. After the engine dies in neutral I must start it again in gear with the throttle a little engaged to keep her running.
__________________
CoCoKnots is offline   Reply With Quote
Old 21-09-2013, 19:31   #6
Registered User

Join Date: Mar 2010
Location: Seattle
Boat: Camper & Nicholsons 38
Posts: 33
Re: perkins 4-108 stalls at idle

Check your injection pump - it typically has a screw (called the anti-stall device) that you need to adjust. If your engine dies when you reduce the RPM to idle, this is a likely suspect. Check your 4-108 manual for instructions on how to adjust the anti-stall device and the idle speed. As a test, you should be able to run your engine at rated continuous RPM (which is 3000 for the 4-108) and then drop it to idle over two seconds, and the engine should settle down at the idle speed correctly.

Van
s/v Rainshadow
__________________
afmstm is offline   Reply With Quote
Old 21-09-2013, 19:39   #7
Senior Cruiser
 
SkiprJohn's Avatar

Cruisers Forum Supporter

Join Date: May 2006
Location: Kea'au, Big Island, Hawaii
Boat: Cascade, Sloop, 42 - "Casual"
Posts: 14,192
Re: perkins 4-108 stalls at idle

I think something is interfering with your throttle control. You need to track it down starting at the engine and investigate every inch of the way and determine if your gear shifting lever and throttle lever are a drag on each other. Have a friend go through the shifting action and throttle action while you are down below looking at the fuel injection pump. Do it while the engine is not running just to see what's happening. Then, do it with the engine running and all your fingers and toes are out of the way of any moving parts, belts, pulleys, etc..

Your engine should idle around 800-850 rpm when you throttle back to shift. Any lower than that and it might die when you engage it in gear. Watch your tachometer or get an electronic tachometer so you can judge the idle speed. Idle speed is adjustable.
__________________
John
SkiprJohn is offline   Reply With Quote
Old 21-09-2013, 21:01   #8
Registered User
 
CoCoKnots's Avatar

Join Date: Jul 2011
Location: Colorado/CoCoa Beach
Boat: Irwin 42
Posts: 61
Re: perkins 4-108 stalls at idle

Thanks Van & John,
Tomorrow's project.
I didn't think about the injection pump.
__________________
CoCoKnots is offline   Reply With Quote
Old 22-09-2013, 10:05   #9
Registered User
 
brutb's Avatar

Join Date: Feb 2011
Location: Cocoa, FL
Boat: Wittholz 39' Cutter by Kanter, CSY 37 Cutter
Posts: 598
Images: 4
Re: perkins 4-108 stalls at idle

CocoKnots, I am on Merritt Island and have a 4-108 service manual if you need one and if you do not have a helper, pm me and I will try to assist.
SV Magic
SV Iron Jack
__________________
brutb is offline   Reply With Quote
Old 22-09-2013, 12:49   #10
Registered User
 
Dynamo1181's Avatar

Join Date: Jun 2010
Location: Bahamas - Maine
Boat: '88 Passport 41' Magic Moments
Posts: 197
Re: perkins 4-108 stalls at idle

I will be in Melbourne for 5 mos starting 11/1. Would be glad to help. I have been intimate with my 4-108 for more than 20 yrs. PM if you need a hand.
A
__________________
.............< Alan >..............
><((((> .`.><((((>
........AD4HE & KD4LGZ........
Dynamo1181 is offline   Reply With Quote
Old 25-09-2013, 18:55   #11
Senior Cruiser

Cruisers Forum Supporter

Join Date: Mar 2007
Location: Santa Cruz
Boat: Boatless Again
Posts: 4,310
Re: perkins 4-108 stalls at idle

Its most likely the injector pump--if adjusting the anti-stall to factory specs doesn't solve the problem, you probably need to take the injection pump off and have it rebuilt--tell the rebuilder your symptoms so he double-checks the governor.
__________________
donradcliffe is online now   Reply With Quote
Old 25-09-2013, 21:15   #12
Senior Cruiser
 
River Cruiser's Avatar

Cruisers Forum Supporter

Join Date: Jul 2011
Location: UMR mm 283 /winter in Kansas
Boat: Bayliner 3870 41' oal.
Posts: 817
Is there any other problem other than the stalling at idle rpm, if you bring the throttle slowly to the idle will it still die? If you have no other symptoms out of the ordinary it may be the low idle adjustment isn't set correctly. The low rpm & the high rpm are adjustable, you'll need a photo tach to adjust it.
__________________
River Cruiser is offline   Reply With Quote
Old 03-10-2013, 19:03   #13
Registered User

Join Date: Feb 2013
Location: On the water
Boat: 1976 Schucker 444
Posts: 14
Re: perkins 4-108 stalls at idle

I have a 1975 Perkins 4-108I can't seem to bleed the system completely
The engine looses prime when reved up and has caused me major problems. I have keep the engine running fairly well by running it around 1400 RPM and it has been running and starting right up. Today I started it and it reved up after being in idle and lost prime and wouldn't start. I have gone through every line and it SEEMS to be getting air in between the pump and the main filter. I suspect that the fuel pump isn't keeping up and needs to be rebuit? I took it off and cleaned it and put it back in and got the engine to start but the idle is all over the place. Maybe starving for fuel, then getting it?
I'm in Beaufort NC trying to head south and just spent all my cruising $ on getting ready to go. I'm so frustrated. Any ideas and how hard would it be to rebuild the fuel pump? That diaphragm looks a little tricky and I inspected it and put it back together just cleaning what I could.
__________________
S/V Ever After
Facebook.com/ever.after.9406 - FaceBook
SailOnEverAfter is offline   Reply With Quote
Old 04-10-2013, 00:42   #14
Senior Cruiser
 
SkiprJohn's Avatar

Cruisers Forum Supporter

Join Date: May 2006
Location: Kea'au, Big Island, Hawaii
Boat: Cascade, Sloop, 42 - "Casual"
Posts: 14,192
Re: perkins 4-108 stalls at idle

After you bleed your engine or replace fuel lines those little copper washers become flatter and sometimes allow air to get into your system. Replace a few at a time and trace your fuel system from one fuel line connection to the next. Eliminate each area by bypassing using a can of clean fuel with a fuel line into it. If you find where it loses prime, i.e. fuel filter, replace o rings and washers and top it off and start again. Any little crack in a line or loose fitting or even your fuel tank pickup tube can cause what you experience.
__________________
John
SkiprJohn is offline   Reply With Quote
Old 17-08-2015, 08:18   #15
Registered User

Join Date: Aug 2015
Posts: 2
Re: perkins 4-108 stalls at idle

I have exactly the same problem and have been unable to trace the source. I have adjusted the idle higher and worked with the anti-stall device without success. I note one post that suggests having the high pressure pump overhauled, but would like to know if anyone has had success without going to that amount of work pulling things apart.
__________________

__________________
paldrich is offline   Reply With Quote
Reply

Tags
perkins

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




Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -7. The time now is 12:34.


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.