Yanmar 3GM30 salt water in intake manifold - 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? 
  #1  
Old 03-31-2008
Junior Member
 
Join Date: Mar 2008
Posts: 9
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 0
Peregrina is on a distinguished road
Yanmar 3GM30 salt water in intake manifold

My 1983 3GM30 which I start weekly got difficult to start two weeks ago...I finally got it to start as if it were cold (I am in Puerto Rico) by opening the throttle all the way. Last week, when I tried to start it, it wouldn't even turn over, and, thinking it might be a bad starter connection, I went to visually inspect it...and saw seawater dripping from the air filter above the starter. I apparently had what we used to call a "liquid lock" on radial engines...using the levers to decompress the cylinders, I was able to turn the engine over and that way get rid of the water, then returning to compression, got it to start. I closed the seacock before I shut it off, to avoid leaving it full of water, and I called a mechanic who said he thought it was the syphon arrangement that connects the exhaust manifold with the mixing elbow (which was replaced about 6 months ago) He replaced that, and we started the engine (again full throttle). He said that was probably because it was wet.... That was on Thursday. Yesterday, Sunday, I tried to start it and it wouldn't turn over. The intake manifold was so full of water that it had overflowed and there was water in the air filter. I got it started the same way as before (full throttle after purging it), but I know that if I haven't damaged the engine yet I soon will. Can anyone suggest what the hell is going on?

Thanks,
Chuck (Peregrina, a Freedom 32)
Reply With Quote Share with Facebook
  #2  
Old 03-31-2008
toewsrus's Avatar
Junior Skipper
 
Join Date: Mar 2007
Location: New Hampshire
Posts: 22
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 0
toewsrus is on a distinguished road
Sea Water in the engine. Water Lock, Liquid Lock, whatever you call it, it's not good and will ruin your engine. I have the 3GM30F as well. does yours have an F at the end of the model number, meaning it's freshwater (antifreeze) cooled, or is it strait seawater cooled and no F?

I went to a 3 day Yanmar course last week, I think it was one of the first things he told us: don't crank your engine longer than 20 seconds total (5 seconds now, 5 later, 5 later on and then 5 more) (or 20 seconds all at once). If you do, the muffler must be drained. The seawater will accumulate and not get pushed out by the cranking engine. It's a running engine's exhuast pressure that pushes the seawater overboard.

Liquid Lock will bend or break your connecting rods. I'm not sure of the extent of your damage. But if it's running, I would start with an oil change, then another, and probably a good once over by your mechanic.

If it's not a freshwater cooled (No F after the 3GM30) and the water is coming in by itself and not because of over cranking, I would suspect a blown gasket or crack in the head or block. Either way it involves major engine work.

Please let us know how it goes!
__________________
Mike


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



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


The slight variations in spelling and grammar have been added in order to enhance this post's individual character and beauty and in no way are to be considered flaws or defects.

Let's Roll
This is the Great Adventure
Reply With Quote Share with Facebook
  #3  
Old 03-31-2008
MedSailor's Avatar
Closet Powerboater
 
Join Date: Mar 2008
Location: Anacortes PNW
Posts: 2,552
Thanks: 81
Thanked 54 Times in 46 Posts
Rep Power: 7
MedSailor is on a distinguished road
What makes you think you have a liquid lock? If you have sea water dripping on the starter and it got PROGRESSIVELY harder to start you might just have corrosion on the starter/solenoid connections. This is very easy to diagnose. First, look at the connections. Do they look corroded?

Take a multimeter and test your voltage at the battery posts. Hopefully it is 12.8V. Then test it on the two posts of the solenoid. Is it 12.2? That would make the engine start sluggishly.

To fix take off and clean the connections. Oh and fix the saltwater leak. I would recommend removing the battery cables at the battery first though as I once touched both poles of the solenoid with a metal wrench. It instantly arc-welded the wrench to the posts and began starting the engine. Scared the %%$$!!! out of me!

You also may have corrosion in the starter. I once submerged my yanmar starter in sea water (don't ask) and it was pretty straight forward to "carefully" pull it apart, clean it and put it back together using the exploded diagram from the yanmar manual.

Hope this helps.

MedSailor
Reply With Quote Share with Facebook
  #4  
Old 03-31-2008
jrd22's Avatar
Courtney the Dancer
 
Join Date: Nov 2000
Location: San Juan Islands., WA, USA
Posts: 3,817
Thanks: 3
Thanked 15 Times in 15 Posts
Rep Power: 14
jrd22 will become famous soon enough
We have the same engine and I once got seawater in the cylinders while trying to bleed the injection system before I knew it could happen(actually flooded the engine 2-3 times before figuring it out-kind of a high stress situation). The engine was OK (this happened several years ago) but got progressively harder to start over the next year or so. We eventually had the injectors reconditioned and it helped the hard starting quite a bit. The salt water is really hard on the injector nozzles, they don't atomize the fuel properly making it harder to ignite. I don't understand how you are continuing to get water in the engine if you have your seacock closed after you shut the engine down. Is there any way water can be siphoning back through the exhaust system?

Good luck,
John
__________________
John
SV Laurie Anne

1988 Brewer 40 Pilothouse

Reply With Quote Share with Facebook
  #5  
Old 03-31-2008
Junior Member
 
Join Date: Mar 2008
Posts: 9
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 0
Peregrina is on a distinguished road
John:
Thanks for replying...I suspect the ever-more-difficult starting may be what you describe with respect to the injectors...but before I can fix those I have to figure out where the water is coming from. I have actually been closing the seacock before shutting down the engine to try and avoid having water retained in the manifold...but where's it coming from? The hose that connects between the exhaust manifold and the mixing elbow is routed in a high curve to theoretically preclude syphoning...so far I'm not getting water in the engine oil, but that'll be the next thing if my rings seize up.... Is a puzzlement.
Chuck
Reply With Quote Share with Facebook
  #6  
Old 03-31-2008
Junior Member
 
Join Date: Mar 2008
Posts: 9
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 0
Peregrina is on a distinguished road
Mike:
Which came first, the slow starting or the chicken? Or the egg? After reading what you point out about the 20-second cranking, I think you've answered where the salt water's coming from. But this engine was rebuilt about a year ago, and we used it last summer upwind to St. Thomas on the way to Virgin Gorda, and later at Thanksgiving on the way to St. John...but now instead of asking where the water's coming from I should be asking why's it starting so hard...what fouled the injectors?
Reply With Quote Share with Facebook
  #7  
Old 03-31-2008
Senior Member
 
Join Date: Sep 2006
Posts: 2,209
Thanks: 0
Thanked 1 Time in 1 Post
Rep Power: 9
Rockter will become famous soon enough
Well, you are either syphoning, or you have breached the exhaust manifold barrier between coolant and combustion exhaust.
I trust you have a siphon break? If so, make sure it's working. Check the wee non-return valve on it.
If that does not work, then take the exhaust manifold off there and you should see the leak path across the gasket(s). The gasket will not leak inward when running, but it will when shut down. If the drip was fairly fast out of the air filters, I would not suspect the exhaust gasket.
Reply With Quote Share with Facebook
  #8  
Old 03-31-2008
Senior Member
 
Join Date: Nov 2002
Location: New York
Posts: 5,573
Thanks: 0
Thanked 14 Times in 14 Posts
Rep Power: 14
bubb2 has a spectacular aura about bubb2 has a spectacular aura about bubb2 has a spectacular aura about
Check your vented loop
Reply With Quote Share with Facebook
  #9  
Old 03-31-2008
Junior Member
 
Join Date: Mar 2008
Posts: 9
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 0
Peregrina is on a distinguished road
Rocter:
Thanks! I was away from the boat (I live in the mountains) and had a mechanic check the siphon...he took out a pvc that was mounted between the exhaust manifold and the mixing elbow...no valve whatsoever in that...and installed another "antisyphon" loop...which looks pretty much the same to me; a short hose going up, a fitting, and another coming down to the elbow, with a small tube clipped to the firewall with one end open. I confess I don't understand how that works, and my Yanmar documentation doesn't show anything like that. It was actually more than a drip; there was water standing in the manifold and what was dripping was leaking out of the filter cover....
Chuck
Reply With Quote Share with Facebook
  #10  
Old 03-31-2008
jrd22's Avatar
Courtney the Dancer
 
Join Date: Nov 2000
Location: San Juan Islands., WA, USA
Posts: 3,817
Thanks: 3
Thanked 15 Times in 15 Posts
Rep Power: 14
jrd22 will become famous soon enough
If the water you saw dripping from the air cleaner and in the intake manifold was saltwater then I don't think you have a leak into the coolant jacket. When trying to start it leave the seacock closed until it fires off then open immediately, running the engine is the best thing you can do for it right now to get oil on the cyl. liners and rings. Have you been able to run the engine since installing the siphon break, has it stopped the water from filling the engine?

John
__________________
John
SV Laurie Anne

1988 Brewer 40 Pilothouse

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
Windward performance deseely General Discussion (sailing related) 21 04-01-2012 02:42 PM
Potable Water tdw Provisioning 31 08-11-2007 07:30 AM
Flushing/testing/preping an old water system on a new old boat tenuki Gear & Maintenance 8 04-19-2007 10:33 PM
Salt Water Cooling System failure. rclampitt Gear & Maintenance 4 07-28-2002 09:26 PM
Water Ballast/Manufacturer RSJ Boat Review and Purchase Forum 6 03-07-2002 05:59 PM


All times are GMT -4. The time now is 10:47 AM.

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.