Runaway diesel - Page 5 - SailNet Community

   Search Sailnet:

 forums  store  


Quick Menu
Forums           
Articles          
Galleries        
Boat Reviews  
Classifieds     
Search SailNet 
Boat Search (new)

Shop the
SailNet Store
Anchor Locker
Boatbuilding & Repair
Charts
Clothing
Electrical
Electronics
Engine
Hatches and Portlights
Interior And Galley
Maintenance
Marine Electronics
Navigation
Other Items
Plumbing and Pumps
Rigging
Safety
Sailing Hardware
Trailer & Watersports
Clearance Items

Advertise Here






Go Back   SailNet Community > On Board > Gear & Maintenance
 Not a Member? 


Like Tree4Likes
Reply
 
LinkBack Thread Tools
  #41  
Old 05-22-2013
captbillc's Avatar
ancient mariner
 
Join Date: Jul 2008
Location: duluth ,minnesota
Posts: 422
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 7
captbillc is on a distinguished road
Re: Runaway diesel

running away means the engine continues to speed up . if you don't stop it , it will fly apart. it is a scary situation .
__________________
Liberals are people who care about others. Freethinkers are not constrained by the myths of religion.
Reply With Quote Share with Facebook
  #42  
Old 05-22-2013
Senior Member
 
Join Date: Oct 2011
Location: Victoria b.c.
Posts: 1,552
Thanks: 2
Thanked 18 Times in 18 Posts
Rep Power: 3
Capt Len is on a distinguished road
Re: Runaway diesel

So a large eastcoast dragger is coming into a crowed port. The oiler, trying to get a head start on shore leave has removed,cleaned and rinsed (with diesel fuel) the air filters .He re installs.Wow. suddenly engine is way past governed RPM. Take her out of gear and probably disintegrate or do a fancy two step in small places. Excessive RPM can be interesting. My best experience was a friends hot chevy . Carb linkage over centered and pressure plate bounced off the pavement , came back up through the radio , dashboard and windshield into the night.Presence of mind (turn off the key) would have helped.

Last edited by Capt Len; 05-29-2013 at 11:36 PM.
Reply With Quote Share with Facebook
  #43  
Old 08-15-2013
Senior Member
 
Join Date: Sep 2010
Posts: 246
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 4
steel is on a distinguished road
Re: Runaway diesel

I don't think anyone mentioned this, but you can use a CO2 fire extinguisher to stop a run away diesel.
Bruce_L and Lateen Luffer like this.
Reply With Quote Share with Facebook
  #44  
Old 08-15-2013
Senior Member
 
Join Date: May 2012
Location: Lund British Columbia
Posts: 100
Thanks: 0
Thanked 1 Time in 1 Post
Rep Power: 3
Bob142 is on a distinguished road
Re: Runaway diesel

As long as you are not in danger of hitting anything you are better to leave it turning the prop as disengaging will allow the engine to rev higher and faster...
__________________
Bob142
Desolation Sound
Maple Leaf 48

Any storm in a port...
Reply With Quote Share with Facebook
  #45  
Old 08-15-2013
zeehag's Avatar
snake charmer, cat herder
 
Join Date: Nov 2008
Location: refitting a formosa in exotic tropical locations....
Posts: 1,636
Thanks: 4
Thanked 23 Times in 23 Posts
Rep Power: 6
zeehag is on a distinguished road
Re: Runaway diesel

Quote:
Originally Posted by chucklesR View Post
Run away on oil has happened to me once.
I put too much oil in while changing it (boat wasn't level while on the hard), then on my first time out decided to test throttle to max RPM. Frothed it right up. Huge clouds of blue smoke and no throttle control all of a sudden.

The governor doesn't do a thing, it only shuts off/restricts the diesel fuel - so the engine continues to get a full load of 'fuel' from the oil froth.
The fuel shutoff (mechanical and electrical both) does exactly as much good as the governor, none.

Since it's got PLENTY of fuel there and air coming in the engine just does what it is designed to do and runs at full out to use all the fuel coming in, and of course more fuel means higher rpm.

The only way to stop it is to choke air (a rag in the intake) or decompress the engine by tripping the lever on the engine.
You'll need to recognize the condition of run away quick - spinning parts at 4000+ RPM can quickly destroy an engine.

Having had it happen to me just once was enough. I keep a rag zip tied in the the air intake area as well as a zip tie (red) on the decompression lever. It's hard enough to stick your face and hand into a engine compartment with an engine that might be exploding in seconds - doing that and then having to look around for a rag/lever doubly sucks.
if the problem is with the fuel delivery system, as mine seems to have been,maybe, the engine will stop running when all injectors are cracked. my engine is perkins .. they are difficult to cut air.

runaway diesel is also caused by engine using its own lube oil to run and continues to increase rpms until overheat and detonation. this one must cut off air flow or ditch compression so it stops or it will detonate and you can lose boat. this cause is not fixed by cracking injectors, i have been advised.

this is mainly caused by excessive blowby, excessive cylinder wear, ring failure...worn, broken, cracked....
mine so far seems to have been fuel delivery initiated.
__________________

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

formosa 41 and ericson 35mII
cruising tropical mexico at present, working my way southward



To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Last edited by zeehag; 08-15-2013 at 11:41 PM.
Reply With Quote Share with Facebook
  #46  
Old 08-16-2013
Melrna's Avatar
Crazy Woman Boat Driver
 
Join Date: Apr 2004
Location: New Bern NC
Posts: 783
Thanks: 16
Thanked 12 Times in 9 Posts
Rep Power: 11
Melrna will become famous soon enough
Send a message via AIM to Melrna Send a message via Yahoo to Melrna
Re: Runaway diesel

I would not use a rag as it can get sucked up and destroyed into the engine. Instead I would use a piece of wood or something hard over the intake.
zeehag likes this.
__________________
Melissa Renee
Moondance
Catalina 445, Hull #90
Reply With Quote Share with Facebook
  #47  
Old 08-16-2013
Junior Member
 
Join Date: Feb 2007
Location: Central Coast of California
Posts: 8
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 0
goehner2 is on a distinguished road
Re: Runaway diesel

We had an old carrydeck crane with a diesel engine that became notorious for not shutting down or overrunning. We installed a ball valve just down stream of the the air filter so we could stop the engine. If your filter housing is threaded to the air intake tube, it would be an easy install, assuming you have room for the valve.
MedSailor likes this.
Reply With Quote Share with Facebook
  #48  
Old 08-16-2013
TQA's Avatar
TQA TQA is offline
Bombay Explorer 44
 
Join Date: Apr 2009
Posts: 2,435
Thanks: 0
Thanked 33 Times in 29 Posts
Rep Power: 6
TQA is on a distinguished road
Re: Runaway diesel

The two scenarios for engine runaways are

1 Pneumatic governor usually the single pipe. I have seen an old Mercedes boat engine with one of these. If the pipe breaks or the diaphragm fails they will runaway. You can pull the stop control and the engine will stop.

2 Any engine where the crankcase breather feeds into the inlet manifold. If there is any significant frothing of the crankcase oil and it passes through whatever trap is fitted you get a runaway. Pull the stop control and the engine will not stop you have to cut off the air supply.

If I got a runaway and could not get to the air inlet to stuff a rag in I would pull the decompressor if my engine had one. What ever damage would be done would be less than the catastrophic failure you get from a runaway. Worth doing a dry run to find if you need to remove something to block the inlet. Perkins diesels often have a filter that I would need to be removed before applying the rag.

While I have never witnessed a runaway that actually resulted in an engine failure that was catastrophic I have taken the breakdown truck to a Commer 2 stroke that had run away and so had the driver. There were bits everywhere and one of the pistons was embedded in a brick wall many yards away.

Last edited by TQA; 08-16-2013 at 06:15 PM.
Reply With Quote Share with Facebook
  #49  
Old 08-16-2013
Member
 
Join Date: Sep 2010
Posts: 39
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 0
foggysail is on a distinguished road
Re: Runaway diesel

Years ago I had a run away in my Hunter 30 powered with a 12HP Yanmar better suited for rice patties. I over filled the crankcase. Started the engine, things seemed fine and then it started to race even though I pull the fuel lever all the way back

Yeah, I knew what could happen so I quickly put the transmission in gear and let the boat do wide circles until the run away stopped. No damages
Reply With Quote Share with Facebook
  #50  
Old 08-16-2013
Cap-Couillon's Avatar
Noah's Bosun
 
Join Date: Jan 2013
Posts: 103
Thanks: 2
Thanked 18 Times in 17 Posts
Rep Power: 2
Cap-Couillon is on a distinguished road
Re: Runaway diesel

Have used the CO2 fire extinguisher method to kill a runaway. It works, but make sure its CO2 not dry-chem. Just as an aside, here is a vid of a 1930's Rapp Semi-Diesel (2 stroke) running away from an overfilled crankcase.
__________________
"I reckon I got to light out for the Territory ahead of the rest, because Aunt Sally she's going to adopt me and sivilize me, and I can't stand it. I been there before." (H. Finn 1884)

Onboard - Solitaire
Reply With Quote Share with Facebook
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

 
Posting Rules
You may post new threads
You may post replies
You may post attachments
You may edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Runaway Diesel Flybyknight General Discussion (sailing related) 10 12-15-2012 10:28 AM
Recommend addition to Runaway Diesel article. scraph Announcements and Suggestions Box 1 03-02-2010 12:49 AM
runaway boat Karletto Learning to Sail 10 08-26-2008 10:55 AM
Runaway Diesel.. or not? jr438234606 Gear & Maintenance 9 06-13-2006 02:02 PM
Runaway Diesel Engine Ben Hilke Gear and Maintenance Articles 0 07-19-2004 08:00 PM


All times are GMT -4. The time now is 10:59 PM.

Add to My Yahoo!         
Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
SEO by vBSEO 3.6.1
(c) Marine.com LLC 2000-2012

The SailNet.com store is owned and operated by a company independent of the SailNet.com forum. You are now leaving the SailNet forum. Click OK to continue or Cancel to return to the SailNet forum.