Cooling system problems. Need some help. - 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 > Engines > Diesel
 Not a Member? 

Diesel This is a forum dedicated to diesel engines and their applicable accessories.


Reply
 
LinkBack Thread Tools
  #1  
Old 08-03-2009
Beersmith's Avatar
Sailing to surf
 
Join Date: Nov 2008
Location: St. Augustine, FL
Posts: 208
Thanks: 1
Thanked 0 Times in 0 Posts
Rep Power: 6
Beersmith is on a distinguished road
Unhappy Cooling system problems. Need some help.

I recently purchased a 1975 Downeaster 38' Cutter, re-powered in 1994 with a Yanmar 4JH2E. It only has about 900 hours on the engine, but has been sitting unused for a few years now. I live in Orlando, FL but the boat is in Inglis, FL near Crystal River in the Big Bend area at the sellers dock. He is being kind enough to let me keep it there until I get it in shape to take it elsewhere. So I am limited to making weekend trips up there for now.

When we did the sea trial, the engine performed just fine. We ran it up and down the river for almost 3 hours with no problems at all. I had not taken her out since then (about a month) and have just been doing a lot of cleaning and work replacing the running rigging. Two weekends ago I decided it was time to take her out on the river (its on the Withlacoochee River) and show some friends a good time. Before we went out, I checked all fluids, cleaned out the raw water strainer and topped off the coolant. I noticed there was no rubber gasket or anything on the cap of the raw water strainer, just a metal plate. I didnt think much of it at the time, but now I wonder if there should be one.

The engine ran just fine for about an hour up the river. At one point, I revved it up to 2,800 rpms to see how it responded at cruising speed. Soon after my heart sank as I noticed steam (of course I first thought it was smoke and we were burning down) gushing out of the engine room. I quickly shut it off and had to release the anchor for the first time on the boat (something I needed to learn soon, but in less stressful circumstances).

The cap on the expansion tank for the cooling system had popped off and the cooling water was steaming everywhere. I also noticed that the air silencer had popped off and was hanging by a hose. I had checked it before we left and may have not secured it correctly. So I topped off lost coolant and let the engine rest for a while.

It was getting dark soon and we needed to get back. The engine cranked up just fine but after a short while the temperature was running high. Right before we got to the dock the cap on the expansion tank popped off and once again steam goes everywhere.

We had to go back to Orlando for the week so I did some research and stupidly realized that I didn't check if water was flowing out of the exhaust at all. I had also remembered that the belt was pretty loose, so those were first on the list to check when I came back. I would make sure to double check how I closed the water strainer.

So I go back to the boat this previous weekend. I tighten the belt after much hassle and checked to make sure the raw water strainer is tightly sealed. I then started the engine and first checked to see if any water was coming through the exhaust....none . So my guess is that the problem lies in the raw water circuit somewhere, correct?

I planned on checking and replacing the impeller, of which the previous owner already had a new spare. I soon realized that the impeller is in a hellish place where I can only fit one arm with barely enough room to move a tool. Removing the cover plate for the impeller was tricky, but I did it without loosing my cool. Then I realized that I would not be able to take the impeller out with any ease. I hoped to use the 2 screwdriver method to pry it out, but there was no way I could get two of them in there. I spent the majority of my day getting frustrated over figuring out how to get the impeller out, and didn't get much else done.

The only other thing I checked was to make sure there was nothing blocking the through-hull. I popped the inlet hose from the raw water strainer and was able to suck water through, so that was clear at least.

After leaving my dad asked if I checked to make sure the impeller was even turning after the engine was on...no, I didn't check .

The boat is old, but the engine is the one thing I was happy to have working fine. This completely has left me in the dumps emotionally, and then to cap it off I got cut to part-time at work this week amidst a bunch of lay-offs. Im lucky I still have the job, but loosing 20% of my salary takes away the extra money I was using each month to get the boat in shape.

So that is where I am. What steps should I take this weekend while I am there? I assume to make sure the impeller is even turning by running the engine with the cover off? Do I start to just pull hoses at various points along the circuit to see if water is flowing? Am I limited to buying an impeller puller or is there a cheaper tool I don't know about?

Any help isolating the problem would be appreciated. I hope I can get this done without paying someone to come out to the boat. I am willing to learn and do the hard work, but need some sage wisdom.

Thanks!
__________________
My boat rebuild/sailing blog:
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
Reply With Quote Share with Facebook
  #2  
Old 08-03-2009
HerbDB's Avatar
Senior Member
 
Join Date: Sep 2000
Location: Eastern Pennsylvania
Posts: 203
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 14
HerbDB is on a distinguished road
You have done a pretty good job of troubleshooting the problem. Since water is getting past the thru hull, and the water strainer is clear, the the problem is most likely the water pump.

You fixed the loose belt, so that leaves the impeller as the likely problem.

On my boat, I can get to the pump fine, but the pump cover is on the back side, so I have to remove the pump to change the impeller. I disconnect the hoses and remove the pump on its bracket.

It's easier to change the impeller working on a table. Be sure to lube the new impeller (olive oil works well) before you put it in. Make sure you retrieve any broken impeller blades that might be loose in the case or output hose.
__________________
Herb DuBois
Beneteau 36CC
Split Decision
Reply With Quote Share with Facebook
  #3  
Old 08-16-2009
Member
 
Join Date: Aug 2009
Posts: 78
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 6
flatracker is on a distinguished road
I recently had

I recently had a brand new, maybe 10 hours on it, Yanmar impeller spin the center hub. It looked perfect the first time I checked it. If this is the case, replace it with a Johnson brand impeller. Easy to spot, as the Johnson has a screw which goes all the way through the impeller, not just the pin. Apparently this is not a real unusual happening, so from now on I will only have the Johnson impellers on my boat.
__________________
Dream like you will live forever. Live like you will die tomorrow. ( James Dean )
Reply With Quote Share with Facebook
  #4  
Old 08-16-2009
Selkirk's Avatar
Senior Member
 
Join Date: Feb 2009
Location: Tupelo, MS
Posts: 190
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 6
Selkirk is on a distinguished road
Quote:
Originally Posted by Beersmith View Post
........................I then started the engine and first checked to see if any water was coming through the exhaust....none . So my guess is that the problem lies in the raw water circuit somewhere, correct?...............
Absolutely! You should be thrilled that your problem has revealed itself in this way because then you will know when you have fixed it.
And I'm betting that you never, ever leave the dock again without making a casual glance over the stern.....
__________________
When you come to a "Y" in the road, take it....Yogi Berra
Reply With Quote Share with Facebook
  #5  
Old 08-16-2009
Junior Member
 
Join Date: Aug 2009
Posts: 27
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 0
lordpoltimore is on a distinguished road
i take it that this engine is cooled by sea/river water pumped around the engine , as to a close system were it has a heat exchanger ????
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
Raw Water Cooling System Questions morgantheship Gear & Maintenance 19 11-17-2008 07:07 PM
12v system and 24v system on 1 boat at same time? BigCatOne Gear & Maintenance 5 05-21-2007 07:55 PM
Outboard cooling system happyseidlemannowner Gear & Maintenance 6 05-04-2006 11:28 AM
Sailing with E-Mail Kathy Barron Cruising Articles 0 09-04-2000 08:00 PM


All times are GMT -4. The time now is 12:45 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.