Cruisers Forum
 


Join CruisersForum Today

Reply
 
Thread Tools Rate Thread Display Modes
Old 05-12-2011, 20:47   #1
Registered User

Join Date: Dec 2010
Posts: 40
Losing Coolant - Need Some Advice

Hello all, I have an issue. I have a Perkins prima 50 that looses about a cup of radiator fluid an hour. I have tried dyeing the coolant a very dark color to see if it would come out my exhaust system, but as my exhaust pumps out raw water at a few gallons a minute I couldn't tell if there was any change in color. The engine runs great exept for this issue. There is a small amount of white smoke at the start up but none after a couple of minutes of running. I have a very dry bildge, and have found no sign of coolant in my engine pan. The oil looks to be in great shape and not cloudy at all. This has been going on for over a month now and I really want to get it fixed. Does anyone have any good ideas? Tomorrow I am going to try and rent a radiotor pressure tester, but I'm not sure what that will tell me other than that I am loosing radiator fluid which I already know. Any help would be appreciated.
__________________

__________________
keao is offline   Reply With Quote
Old 05-12-2011, 20:57   #2
Registered User

Join Date: May 2011
Location: Canada
Boat: Chrysler 26
Posts: 4
Re: Loosing coolant need some advice

pressure test the heat exchanger. a leak there means coolant is joining cooling water and exiting through exhaust
__________________

__________________
coma is offline   Reply With Quote
Old 05-12-2011, 21:03   #3
Senior Cruiser
 
osirissail's Avatar

Cruisers Forum Supporter

Join Date: Feb 2009
Location: A real life Zombie from FL
Boat: Gulfstar 53 - Osiris
Posts: 5,416
Images: 2
Re: Loosing coolant need some advice

+1 for "coma" - Perkins usually have copper tube heat exchangers that rapidly dissolve if not kept properly "zinc'ed."
__________________
osirissail is offline   Reply With Quote
Old 05-12-2011, 21:26   #4
Senior Cruiser
 
delmarrey's Avatar

Cruisers Forum Supporter

Join Date: Mar 2003
Location: Now in Blaine, WA
Boat: Modified Choate 40
Posts: 10,702
Images: 122
Re: Losing Coolant - Need Some Advice

+2 Pressurise the coolant system with the exhaust elbow off. I suspect the H E as well.
__________________
Faithful are the Wounds of a Friend, but the Kisses of the Enemy are Deceitful! ........
A nation of sheep breeds a government of wolves!

Unprepared boaters, end up as floatsum!.......
delmarrey is offline   Reply With Quote
Old 05-12-2011, 21:39   #5
Registered User
 
marc2012's Avatar

Join Date: Apr 2008
Location: abbeville la
Boat: seawind II Patience
Posts: 542
Re: Losing Coolant - Need Some Advice

When my hx went out raw water was getting into the coolant.marc
__________________
marc2012 is offline   Reply With Quote
Old 05-12-2011, 21:52   #6
Registered User

Join Date: Aug 2009
Location: Boston, MA
Boat: Beneteau Oceanis 43 & S2 6.9
Posts: 963
Re: Losing Coolant - Need Some Advice

Is there any issue starting the engine after its been running for awhile.

I'm not an expert on engines, certainly not boat engines, but I did have a coolant issue with a snowmobile we have and one of the rubber header gaskets was bad. Engine would run, but was awful starting up after being used - especially when it was only shut off for a short time. It was clear that it was burning coolant though due to the smell and smoke, but it was much less noticeable when the engine had been sitting.
__________________
maytrix is offline   Reply With Quote
Old 05-12-2011, 22:24   #7
Registered User

Join Date: Dec 2010
Posts: 40
Re: Losing Coolant - Need Some Advice

Thanks for all the suggestions. I will give the pressure tester a try while the exhaust elbow is off.
I do not believe there is any salt water getting into the coolant. An old timer recommend me tasting it ( no swollow) if it's sweet and not salty it's good. If it's salty at all bad news.
__________________
keao is offline   Reply With Quote
Old 06-12-2011, 03:22   #8
Moderator Emeritus
 
Ex-Calif's Avatar

Cruisers Forum Supporter

Join Date: May 2007
Location: Singapore
Boat: Maxi 77 - Relax Lah!
Posts: 11,514
Images: 4
Re: Losing Coolant - Need Some Advice

If it's ethelyne glycol I wouldn't taste it. I'd get my kid to taste it...

+3 on the HE.
__________________
Relax Lah! is For Sale <--- Click
Click--> Custom CF Google Search or CF Rules
You're gonna need a bigger boat... - Martin Brody
Ex-Calif is offline   Reply With Quote
Old 06-12-2011, 03:50   #9
Registered User
 
Jamel's Avatar

Join Date: Oct 2009
Location: Beautiful South West Western Australia
Boat: Catalina 42 Pacific cruise to Australia
Posts: 223
Re: Losing Coolant - Need Some Advice

The clue that I would encourage you to follow is the white smoke at startup. There may be a small hole developing at the cylinder headgasket that allows your coolant to enter a cylinder in smal lamounts. At startup this maybe evident by the smoke but once running and engine heated that smoke dissapears.The coolent evaporates with the heat and very little finds its way to the oil.
__________________
Jamel is offline   Reply With Quote
Old 06-12-2011, 04:06   #10
Moderator Emeritus
 
Ex-Calif's Avatar

Cruisers Forum Supporter

Join Date: May 2007
Location: Singapore
Boat: Maxi 77 - Relax Lah!
Posts: 11,514
Images: 4
Re: Losing Coolant - Need Some Advice

A head gasket leak is a possibility but the HE is an easier check.

Head gasket leaks -
Coolant to cylinder - Presurizes coolant system, bubbles may be seen with coolant cap removed, low compression test
Coolant to oil pressure passage - oil in coolant sytem
Coolant to oil drain passage - Water in oil
Coolant to intake port - Maybe undetecable, possible rust build up in valve guide area.
Coolant to exhaust port - Probably undetectable

Rule of thumb for pressures -

Cylinder pressure - highest
Oil pressure - Second
Coolant pressure - third
Oil return - lowest

Leaks flow from high pressure to low pressure.

1 - It is very, very unlikely that coolant will flow across a headgasket failure into the cylinder.
2 - If enough water to cause white smoke leaked into the cylinder while "static" and did not flow past the rings into the oil sump, it would surely cause a hydraulic lock upon trying to start the engine.
__________________
Relax Lah! is For Sale <--- Click
Click--> Custom CF Google Search or CF Rules
You're gonna need a bigger boat... - Martin Brody
Ex-Calif is offline   Reply With Quote
Old 06-12-2011, 06:19   #11
Senior Cruiser
 
colemj's Avatar

Cruisers Forum Supporter

Join Date: Oct 2005
Location: Presently on US East Coast
Boat: Manta 40 "Reach"
Posts: 10,049
Images: 12
Re: Losing Coolant - Need Some Advice

Check the rubber end caps connecting the heat exchanger to the manifold tank and separating the fresh and raw water systems. There are two hose clamps - the smaller one clamped to the heat exchanger tube bundle and the large clamped to the manifold tank. If they are not clamped properly, the raw and fresh sides will mix. These are a bit tricky to seat correctly, and are the most common cause of coolant loss in these engines.

The part I am describing is the two rubber caps on the top of this picture - one on each side of the tank.

Mark
Attached Thumbnails
Click image for larger version

Name:	veneen-varusteet-ja-varaosat-volvo-penta-409670_b_053e5a8e9a2b4688.jpg
Views:	518
Size:	32.2 KB
ID:	34476  
__________________
www.svreach.com

You do not need a parachute to skydive. You only need a parachute to skydive twice.
colemj is offline   Reply With Quote
Old 06-12-2011, 06:56   #12
Registered User

Join Date: Jul 2009
Posts: 774
Re: Losing Coolant - Need Some Advice

It could be the tube stack, but more likely the head gasket as your dye would color the exhaust outflow. Check your oil, taste for salt; if it's good make a salad.
__________________

Seahunter is offline   Reply With Quote
Old 06-12-2011, 07:12   #13
Senior Cruiser
 
colemj's Avatar

Cruisers Forum Supporter

Join Date: Oct 2005
Location: Presently on US East Coast
Boat: Manta 40 "Reach"
Posts: 10,049
Images: 12
Re: Losing Coolant - Need Some Advice

Check those rubber end caps before tearing anything apart. They are, by far, the most common cause of coolant loss in these engines. Make sure you have a good seal on both the tube stack and the manifold tank - particularly check the seal on the tube stack.

You will not see a change in exhaust color (without fluorescent dye and a UV light) if the leak is a cup of coolant per hour - that is a thimble full per minute.

The tube stack is not copper and the design does not have a zinc.

A pressure test will most likely lead you astray into tearing apart and replacing a heat exchanger. If the rubber boots are not set correctly, the pressure test will fail but you will assume the heat exchanger is bad and go about spending a lot of money and time fixing it for no reason.

Head gasket coolant leaks are the least likely cause of loss of coolant in most engines, and definitely this engine.

I'm not sure why everyone is jumping to a catastrophic failure conclusion when there is a known, simple issue with a coolant system component of these engines.

Mark
__________________
www.svreach.com

You do not need a parachute to skydive. You only need a parachute to skydive twice.
colemj is offline   Reply With Quote
Old 06-12-2011, 08:03   #14
Registered User
 
svHyLyte's Avatar

Join Date: Mar 2006
Location: Tampa Bay area, USA
Boat: Beneteau First 42
Posts: 3,434
Images: 25
Re: Losing Coolant - Need Some Advice

You might obtain some water soluable UV dye and add a few drops to your cooling system and then check your raw-water output with a "Black Light". Odd's are, however, that either the rubber gaskets are bad or you dod have a leak in the HX tube bundle.

FWIW...

For an example of UV Dye Testing see:
__________________
"It is not so much for its beauty that the Sea makes a claim upon men's hearts, as for that subtle something, that quality of air, that emanation from the waves, that so wonderfully renews a weary spirit."
svHyLyte is offline   Reply With Quote
Old 06-12-2011, 20:39   #15
Registered User

Join Date: Dec 2010
Posts: 40
Re: Losing Coolant - Need Some Advice

Thanks for all the hel everyone.
Mark I think you may have hit the nail on the head. I pulledthe Hx out and it looks in great shape (not saying it's not leaking though) but he end caps sure do looked cracked and fatigued. I'm looking onto getting them replaced. Once I get new ones I will rig something together to check the hx while it's out. I'll keep you updated.
__________________

__________________
keao is offline   Reply With Quote
Reply

Tags
coolant

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


Similar Threads
Thread Thread Starter Forum Replies Last Post
Coolant Leak Troubleshooting assfortress Engines and Propulsion Systems 13 26-10-2011 10:27
Sailing Sept. 1 from BVI (Tortola) to Panama - Advice, Please Panamajames Atlantic & the Caribbean 12 17-07-2011 11:00



Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -7. The time now is 07:13.


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.