An orange liquid saga…
When we arrived at Las Olas in Fort Lauderdale, it seemed hot down below. When I opened the engine compartment a wave of engine coolant scented humidity at about 120 degrees F hit me. When the engine cooled enough, I pulled the engine cover off and found the engine had burped about a half cup of coolant onto the chemical absorbent pads we keep under the engine. When I topped off the coolant tank it took about a half cup as it hadn’t started pulling enough vacuum to suck coolant from the make-up tank.
The cooling system went on the “Watch List.”
We motored about an hour leaving Las Olas. We motor-sailed two hours into West End on our crossing. We motored out of the marina and sailed to Mangrove and then on to Great Sale. We motored about six hours to Spanish Cay, and since have motored in and out of anchorages. We watched the engine like a hawk.
While the temperature gauge seemed to read high and then did a cha-cha between right on and a tad low, only tiny burps — droplets were found…nothing like Las Olas.
When we arrived here in Marsh Harbour, the make up tank was full and the coolant tank was down by two glugs*. I topped it off; I carefully seated the cap and made a note to buy coolant to augment the 3 gallons we have aboard. We closed the engine cover and got on with the hard life of wintering in the (sub)tropics.
Thursday, I opened the engine cover for a reason now forgotten. The make up tank was missing at least two cups of coolant. When I pulled the cap, the coolant tanks was ten glugs low (about 1/2 cup). There was some coolant on the pads, but not 1/2 cup.
I removed the various covers and such and started looking hard. I detensioned the belt and did a wobble and spin test on the coolant circulation pump — no wobble, it spun like a record turntable, and nothing was coming from (nor it appeared, had ever come from) the weep hole. But I did find droplets. Aha!!
No-ha! they were lingering gravitational laggards from prior events. Swabbing the area with shop towel removed them, and they were not replaced.
I decided I needed to pressure test the system — and of course out of about 200 lbs of tools I didn’t have a “Stant” tester. I walked to NAPA. The listed them as in stock but didn’t have one. I walked to another supplier (round trip about four miles) and they had the top of the line Stant kit with enough adapters to cover every liquid cooled engine on the planet and only wanted $238 USD for it. I walked back to the boat.
I did more thought experiments. I decided to call for help on the Cruisers Net.
Friday morning during “open mike” on the Net I asked if anyone had a coolant system pressure tester. I got an affirmative answer from a boat in our marina!!
When the Net was over, I walked down to the savior boat and after a suitable chat, walked back to the boat with a tester. The short of it was I found a hose clamp allowing a leak past a barbed fitting on the water heater return line. One eighth turn took care of that, and as I had suspected, I discovered the tank cap no longer could sustain the 13.8 psi pressure it was designed for. All told the process took about 90 minutes. Not much later I ordered a tester ($68 USD) from Amazon, and we will pick it up from Green Cove Springs when we get back.
But we still had the question of where did the make-up tank coolant go with the engine not running, getting warm, creating a demand vacuum…
Then it dawned. Every night Janet heated the water heater. This would cause the coolant in the loop from the engine to the hot water heater to get hot and thermally flow back toward the engine. If there was a vapor lock in the cooling system which are not uncommon in weak cap situations, when this coolant cooled it would create a vacuum and sip coolant from the make-up tank over the ten days of not looking in the engine compartment. Maybe. But I have no other plausible story so we’ll stick to that one till proven wrong.
So now a new Cap. It is a 13.8 psi cap. Those are not sold in the automotive supply chain. I called the local Yanmar guy who doesn’t have it in stock…but can get it eventually…it’s the Bahamas…
So I called our boatyard in Galesville and had them ship one. The Fedex charge will be several multiples of the $18 USD Cap price, but it will come in duty free and fast.
We love this cruising life, but we begin to see how one could pull a barge behind with spares…
* A GLUG is the amount of coolant a 1.5l re-used plastic rum bottle delivers as it makes way for the bubble coming in. GLUGS, therefore, vary due to angle of pour, barometric pressure, boat movement, etc.
A GLUG is the liquid analog to an Emeril Lagasse “BAM!”
First GLUGS are often over enthusiastic (OEG). An OEG can range from a DRIBBLE to a !(&$*@^ HAND ME A TOWEL–NOW!
The metric equivalent to a GLUG is LE GLUG,
a DRIBBLE is UNE STRIE LAIDE HUMIDE D’ORANGE,
a !(&$*@^ HAND ME A TOWEL–NOW! is a !(&$*@^ DONNEZ-MOI UNE SERVIETTE, VITE, VITE! (Notice the precursor pre-cursing is a cognate.)