Coolant Level Question

[KenKrawford]

My boat/engine are only 7 months old and I have added coolant twice to the reservoir. Each time the level was about 1/2 " below the ADD line. There is no evidence of a coolant leak around the engine and the temperature stays at 170.
Do I have a problem or should I just forget it and leave it as is?

[LONGHAWK]

I too have experienced something similar. I have not found any leak and I cannot explain the "loss". I have added coolant and a bit of water to or three times over the last 16 months. The reservoir would be down to the add mark.
Sam
LONGHAWK #173

[Triumph]

Same here... but now it seems to have stablized. This was something i experienced that has stopped. I changed the internal zinc, and have recently run the engine hard. Can't expalin it .

[Bills]

From day one my coolant level is fine during the summer, however, during the winter the bulk of the coolant drains out of the reserve and into the engine bildge. After convincing my dealer that this was not resonable he fixed it. Now it leaks both summer and winter. Amazing. The leak does not seem to involve the engine given the engine coolant seems to always be full and its just the reserve tank that drains. Its only 1/2 broke.

[Allsail68]

Is your coolant level problems when your boats are on the hard? I just returned from checking my boat and the level was down to the add mark. Never had problem in the water/summer. This my first year of storage.

Just wondering if it is caused by angle of storage or temperature or what??

[KenKrawford]

No, my boat stays in the water all year.

[Allsail68]

I am assuming that if it is leaking from the engine it will draw down the reservoir tank accordingly? I know one post said their engine was full, but that would be the case until the reservoir emptied, correct?

[LONGHAWK]

I finally found where some of my coolant was going. I noticed a small "trail" of stains (apparently from the coolant with the anti-freeze solution). It was on the fiberglass pan in front of the engine, just under the water pump. Seems there is some sort of intermittent / small leak there. Anyone else experienced this?

[Allsail]

I just returned from a trip to check on my boat in Annapolis and found the level down about 1/2 inch. This is the second 1/2 inch drop since the cold weather commenced. It is draining to the engine bilge. Did not do it during the summer; therefore, it could be a metal fitting that is shrinking in the cold and causing the slow leak.

U can pressurize the system or wrap suspect fittings with paper towel and check for discoloration when u return to boat to try find these slow leaks.

When my boat was commissioned in the spring the coolant level was down and later found coolant in bilge.

I have placed this item on my dealer warranty list.

[yodagwb]

Allsail


When you find out where the leak is please let me know. I have been fighting with this for 3 yrs and still can't figure out where the leak is. It use to only leak during cold weather (in or out of the water), now that the dealer fix it it leaks year around into the bilge. The radiator is always full even when the reserve tank is completely empty. I guess I will have to go after it with a black light and see if I can track it. I am sure the leak is prior to where the coolant enter the radiator. You just wouldn't think it should be this hard to find.

[Last Boat]

This is my first winter and I have a good heater. My bildges under my engine were dry a short time ago, I now have Engine Coolant in my bildges. I don't see any signs of where the leadage could have come from. Is this like a virus, once you hear about it, you get it? If it is not the cold, how about the lack of use?
Nelson Gainey
Last Boat
C350 #345

[LONGHAWK]

OK, I finally found and fixed my leak. I would occasionaly find coolant in the pan under the engine. I found a very small abraded spot on the clear coolant recovery line. It had touched the engine near the thermostat housing. It was pliable and did not leak as much when warm, but would leak more when the tubing got cold / stiff. I went to an automotive store and bought a replacement hose (about 6 feet in a kit , clear vinyl, advertized as resistant to acids, etc, made by a radiator supply company). Cost about $3 bucks. My problem is apparently fixed.

[Chanticleer]

I really appreciate these forums. They have helped immensely in caring for maintenance items, etc... Last month I brought my boat up from Mobile, AL via the Tennessee Tombigbee waterway. Several 10 hour days under power. I had to add coolant a couple of times as I noticed the level dropping in the reservoir. I had no idea where it was going. I believe my problem is identicle to Longhawk's. I found a weak spot in the clear tubing where it was resting on top of the engine. I'm going to replace with heavier hose tomorrow, and hopefully solve the mystery. Thanks again for sharing.

[Hans Grasman]

Alex and all y'all
I agree this is a great forum but.......... now we seem to know that the coolant loss may be caused by a leaky tube from the coolant reservoir and what are we doing about it?

At this point I think we should pass this on to Catalina for verification and have them send an action item to this forum on how to fix it.
So I am calling on our C350 facilitator, Bill Cullen, to approach Catalina.
I have also been watching this coolant thing for 3 years and could not figure out where the stuff went.

Thank you all for following thru.
Hans
Belcourt #165
PS what are we doing about the fridge/freezer? That is still an open item.

[Richard Ad]

This is MYSTERY. I too have been battling this for 3 years. Last year I replaced my brittle hose that goes to the reservoir with a hefty automotive hose and it was good all summer but in the winter (on the hard this year) I'd got red coolant in my engine bilge. My reservoir was empty by February so I took it off, cleaned it, and checked for cracks or leaks… and found none. During the winter I’d tighten the hose clamps at the heat exchanger and everywhere else I could think where thermal expansion/contraction of different materials might allow a leak. Even with no coolant in the reservoir and the bilge cleaned out I’d still get new coolant in the bilge. I traced the stream running down the sloped engine bilge up to somewhere near the heat exchanger (port side). Coolant level is all the way to the top of my engine manifold pressure coolant cap.

Does anyone know if a faulty manifold pressure cap could cause this to happen??? And, has anyone found the real answer?

[KenKrawford]

Richard, I started this thread over 6 years ago and still haven't fixed the problem. One possible solution that has been suggested (but I havent's checked this yet) is to examine the area around the hot water heater hose connections. Coolant from the engine circulates through the heater and may be leaking out of one of the connections.
If you slay this beast, let us know!

[wolfe10]

My suggestion is to use a pressure tester on the cooling system. Pump it up and see what leaks.

Brett

[sailorbob]

It seems this problem is universal (ha!) to our boats. Most summers, I don't find antifreeze in the engine bilge, but I always do in the winter. My dealer thinks this is about pump seals in the winter and is just a fact of life. Like some of you, I found that the overflow hose to the reservoir didn't stand up well to heat, vibration and rubbing on the engine and suspected it may have been the source of the leak, so I replaced it with a new hose; I got the Universal/Westerbeke part and cut it to fit. Even with a new hose, I still have antifreeze accumulating in the engine bilge over the winter. This winter in fact, not only did the reservoir empty out, but the level in the manifold went down some, too. Is there a better hose, one that withstands heat, chemicals and friction better but is still transparent? Since I still have antifreeze in the bilge, I am not confident that the hose is the leak source.

When I replaced the hose, I refilled the overflow reservoir but never got all of the air to leave the hose, so I don't think antifreeze ran back into the manifold. The reservoir level did not seem to change last season as the engine warmed and cooled. I bought a replacment manifold cap this winter. I will top up the manifold and the reservoir with Dex-Cool 50/50 after launch and see what happens with levels, but my bet is that the cap is not the reason levels in the reservoir do not rise and fall as the engine heats and cools. I would think that heating expansion would drive antifreeze up the hose into the reservoir, driving the air out in the process, and that cooling would pull antifreeze out of the expansion tank into the manifold, but neither of those is happening.

The leak and the air in the overflow line may be basically unrelated problems, but they involve some of the same components. Amazing to me that no one has solved the winter leak problem. And it doesn't sound like it's about seals in the cold, since southern boaters like Ken and northern boaters like me all experience the problem. Long periods of non-use make seals shrink??

As I posted this comment, I saw Brett's suggestion about a pressure tester- how do we laymen get our hands on such a device? Brett - doesn't your engine leak antifreeze?

Bob
Second Wind #301

[wolfe10]

Bob,

No, ours does not leak.

But it is quite possible that this is temperature related. The boat has lived either in FL, TX or in transit to the Bahamas-- so no very low temperatures.

Don't know if it is worth buying a pressure tester. But, some auto parts houses rent tools. Certainly worth a check. And because the system is more likely to leak at cold ambient temperatures test is during the next cold spell.

Brett

[KenKrawford]

Auto Zone loans pressure testers.