Cruisers Forum
 


Join CruisersForum Today

Reply
 
Thread Tools Search this Thread Rate Thread Display Modes
Old 01-05-2020, 14:58   #1
Registered User

Join Date: Feb 2013
Location: Rio Dulce, Guatemala
Boat: Seafarer36c
Posts: 5,533
cooling problem

At any rpm below about 1500 while in gear, the salt water flow stops at some point. Above that it works perfect. After a lot of trouble shooting all I know is, if I disconnect the hose at the output of the pump even for a second, water starts flowing thru the system again. Before you can hear it in the exhaust note, you can feel the pump start to warm up. You would think it might be the impeller, but it was good and the flow is great at higher rpm. There is no blockage in the elbow.
It is a Perkins 4-107.
__________________

Ecos is offline   Reply With Quote
Old 01-05-2020, 15:01   #2
Moderator
 
a64pilot's Avatar

Cruisers Forum Supporter

Join Date: Oct 2013
Location: Jacksonville/ out cruising
Boat: Island Packet 38
Posts: 30,569
Re: cooling problem

Try the pump cover, it may be sucking air or worn, if worn flip it over, also the strainer cap, it too could be sucking air
__________________

a64pilot is offline   Reply With Quote
Old 01-05-2020, 15:11   #3
Registered User

Join Date: Feb 2013
Location: Rio Dulce, Guatemala
Boat: Seafarer36c
Posts: 5,533
Re: cooling problem

The pump cover is as flat as I could make it. Almost no water leaks thru the pump when it's not running. I have a new wiz bang strainer and it does not leak air. The whole system is below the water line and there are no leaks.
Ecos is offline   Reply With Quote
Old 02-05-2020, 01:16   #4
Registered User

Join Date: Jun 2014
Location: Dover, Tasmania
Boat: Pugh windstar 54 Van De Stadt 57 aluminiun ketch
Posts: 30
Re: cooling problem

Does it only happen while in gear? Is there a heat exchanger for the gearbox?
south4320 is offline   Reply With Quote
Old 02-05-2020, 04:40   #5
Senior Cruiser

Cruisers Forum Supporter

Join Date: May 2013
Location: Oregon to Alaska
Boat: Wheeler Shipyard 83' ex USCG
Posts: 2,791
Re: cooling problem

The pump is sucking air from somewhere. It could be the shaft seal, or the cover. Or the impeller or gear drive is slipping on the shaft at low rpm.
Lepke is offline   Reply With Quote
Old 02-05-2020, 05:10   #6
Moderator
 
a64pilot's Avatar

Cruisers Forum Supporter

Join Date: Oct 2013
Location: Jacksonville/ out cruising
Boat: Island Packet 38
Posts: 30,569
Re: cooling problem

Almost no water leaks? Does that mean there are some? I ask as air of course is much less dense than water, and a leak that will only let a small amount of water leak will allow a lot of air.

Did the problem start when something was changed? Like the new strainer?
a64pilot is offline   Reply With Quote
Old 02-05-2020, 08:51   #7
Registered User

Join Date: Feb 2013
Location: Rio Dulce, Guatemala
Boat: Seafarer36c
Posts: 5,533
Re: cooling problem

Almost no water gets past the impeller unless it's turning and the cover fits pretty well. There are no external water leaks, I think the pump is in good shape.
You guys make it sound like an air leak, which is good news cuz I should be able to find it and it won't cost anything.
Ecos is offline   Reply With Quote
Old 02-05-2020, 09:20   #8
Registered User

Join Date: Feb 2013
Location: Rio Dulce, Guatemala
Boat: Seafarer36c
Posts: 5,533
Re: cooling problem

Quote:
Originally Posted by south4320 View Post
Does it only happen while in gear? Is there a heat exchanger for the gearbox?
There is no heat exchanger for the Gear and I have never been able to get a fault in neutral. The problem happens when we motor slowly or motor sail.
When I remove the pump output hose with the engine running, there is a very brief moment when there is no water flow and then it flows as it should.
__________________

Ecos is offline   Reply With Quote
Reply

Tags
cooling

Thread Tools Search this Thread
Search this Thread:

Advanced Search
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


Similar Threads
Thread Thread Starter Forum Replies Last Post
Another Frigoboat Cooling Problem skipgundlach Plumbing Systems and Fixtures 60 02-07-2014 05:39
Baffled by Raw Water Cooling Problem Greg Shakeshaft Engines and Propulsion Systems 23 07-05-2013 17:36
Yanmar cooling problem bobsyouruncle Engines and Propulsion Systems 5 23-12-2011 23:23
Circulation Cooling Problem Mabuhay Engines and Propulsion Systems 4 05-04-2011 11:26
Westerbeke W50 Cooling Problem daedaluscan Engines and Propulsion Systems 5 27-03-2010 21:24

Advertise Here


All times are GMT -7. The time now is 22:58.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2020, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2020, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.