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Coolant in Engine Pan

Apr 5, 2019
31
Catalina 310 323 Avanti Brooklyn, NY
I have noticed (as did the previous owner) an occasional small amount of coolant in the engine pan area after engine run. My rig is equipped with a recovery tank so no overflow. I removed the HX and had it cleaned/pressure tested OK. Inspected and replaced all engine hoses, even though no leaks were detected.
I’ll have it up and running tomorrow afternoon. Fingers crossed
 
Last edited:
Jan 22, 2008
7,032
Beneteau 323 Annapolis MD
Sounds like my 3YM20. Recently when working with the rear egine cover off, I noticed something I had not seen in the months since I've had the coolant on the floor pan. The hose that carries the overfow from the HX filler neck to the recovery tank... There is a hose clamp that is under the pressure cap and it may prevent full seating/sealing of the cap. Or maybe the is not tight?
 

JRT

Feb 14, 2017
1,329
Catalina 310 211 Lake Guntersville, AL
Same issue, some reading here says probably related to overflow hoses and connection. I still haven't found it yet.
 
Feb 5, 2004
3,660
Tartan 3800 Westport, MA
The hose that carries the overfow from the HX filler neck to the recovery tank.
You heat exchanger has a filler neck? I'm only aware of those on radiator tanks, like the wet exhaust manifolds, or remote radiator tanks. (I have both.)
 
Jan 22, 2008
7,032
Beneteau 323 Annapolis MD
You heat exchanger has a filler neck? I'm only aware of those on radiator tanks, like the wet exhaust manifolds, or remote radiator tanks. (I have both.)
I was writing from memory... and heat stroke.
 
Mar 16, 2007
1,314
Catalina 310 Anacortes,Wa
I also replaced my recovery tank, it was cracked and leaking and had coolant in the engine recovery base area.


paulj
:hook2:
 
May 24, 2004
5,854
CC 30 South Florida
Vibration plus changes in temperature and pressure give rise to small momentary leaks from time to time.
 

KZW

May 17, 2014
638
Catalina 310 #307 Bluewater Bay, FL
I bought my boat in Jul 14. I'm the third owner. The level in the tank never moved, not even when I drained the fluid from the manifold to change it. I investigated, and found the hole in the fixture where the hose plugs into the manifold doesn't go through. It looks like it was never drilled out. The face is totally smooth. In the picture posted by Paulj, it looks as if some foreign material may have plugged the hole.

Paulj, what size drill bit did you use?
 
Mar 16, 2007
1,314
Catalina 310 Anacortes,Wa
I bought my boat in Jul 14. I'm the third owner. The level in the tank never moved, not even when I drained the fluid from the manifold to change it. I investigated, and found the hole in the fixture where the hose plugs into the manifold doesn't go through. It looks like it was never drilled out. The face is totally smooth. In the picture posted by Paulj, it looks as if some foreign material may have plugged the hole.

Paulj, what size drill bit did you use?

What did you do for a hole ?
paulj
:hook2:
 

KZW

May 17, 2014
638
Catalina 310 #307 Bluewater Bay, FL
What did you do for a hole ?
paulj
:hook2:

I've lived without one. That being said, I'm planning to drill out now that I know someone else did so and the diameter of hole they drilled.

The good news is the recovery take level stays remarkably consistent. The bad news is the cap on the manifold must be removed to check the coolant level.
 
Mar 16, 2007
1,314
Catalina 310 Anacortes,Wa
I've lived without one. That being said, I'm planning to drill out now that I know someone else did so and the diameter of hole they drilled.

The good news is the recovery take level stays remarkably consistent. The bad news is the cap on the manifold must be removed to check the coolant level.


My advice do not drill the hole.
So many others have not responded to not checking to see if they have a hole drilled thru.
I did not have a problem for 12 years but I just had to drill the hole :yeah:.


paulj
:hook2:
 
Feb 5, 2004
3,660
Tartan 3800 Westport, MA
I say drill the hole. Lack of a hole is an oversight by the manifold manufacturer.


Here is a schematic of a radiator pressure cap. The cap can't work properly without the hole. Your leak may be due to the system becoming over-pressurized.

Note there are two valves, both ported to the overflow vent on the left: a pressure valve and a vacuum valve.
 

KZW

May 17, 2014
638
Catalina 310 #307 Bluewater Bay, FL
My advice do not drill the hole.
So many others have not responded to not checking to see if they have a hole drilled thru.
I did not have a problem for 12 years but I just had to drill the hole :yeah:.


paulj
:hook2:
After drilling the hole, does it work, as advertised?
 
May 20, 2016
2,792
Catalina 36 MK1 Everett, WA
I say drill the hole. Lack of a hole is an oversight by the manifold manufacturer.


Here is a schematic of a radiator pressure cap. The cap can't work properly without the hole. Your leak may be due to the system becoming over-pressurized.

Note there are two valves, both ported to the overflow vent on the left: a pressure valve and a vacuum valve.
Thee overflow tank wasn’t bringing fluid back into the manifold. Then I realized the cap only had the pressure valve and no vacuum. Trip to Napa cured the problem
 
Sep 30, 2008
1,426
Catalina 310 Quincy, MA
I have noticed (as did the previous owner) an occasional small amount of coolant in the engine pan area after engine run. My rig is equipped with a recovery tank so no overflow. I removed the HX and had it cleaned/pressure tested OK. Inspected and replaced all engine hoses, even though no leaks were detected.
I’ll have it up and running tomorrow afternoon. Fingers crossed
For years, my engine has leaked a small amount of coolant, usually when it is at rest. At the beginning of this season, I tightened all the clamps on all the hoses on the engine. None of them had seemed loose at all, but now there is no more leak!
 
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Jan 7, 2011
1,459
Oday 322 East Chicago, IN
For years, my engine has leaked a small amount of coolant, usually when it is at rest. At the beginning of this season, I tightened all the clamps on all the hoses on the engine. None of them had seemed loose at all, but now there is no more leak!
This worked for me too.