kingfisher23
New Member
Technical information: Sea Ray 310 Express running twin MerCruiser 5.7L straght-drive inboards with closed-loop cooling. Engines are (to the best of my knowledge) 1981-vintage and have just slightly less than 2000 hours on them. Well-maintained, from what I can gather. PO was a navy mechanic and did all his own work. Except for the RPM issue, engines were running great before the weekend.
WELL my RPM issue went on the back burner this weekend. We had the family out on Sunday to check out the boat and have a little Labor Day Weekend celebration. I knew my RPMs weren't acting right but the engines still push the boat ok. We loaded up with people and cruised about 5 miles north of the marina to anchor in a little cove for the afternoon. Good times ensued, everyone loves the new boat. Swimming, eating, sitting in the sun, etc. All around, a great time.
Then we headed back south. Boat was making what I could consider "normal" speed given the history of low WOT and the number of people on board. One of my more astute passengers noted a faint exhaust smell coming from the boat. I (perhaps foolishly) put it off as a symptom of someone who has never been on a boat before. :smt021
I started to hear a small ticking sound that seemed to be coming from the starboard engine. It was very quiet, so much that I at first mistook it for a rattling cotter pin on my pilot bench. I had just recognized the sound as a potential problem when the starboard engine RPMs started to waver. We were cruising at 3200, and the tach showed the engine dipping to 2200 or so. I immediately backed off the throttles.
At that moment, I heard a loud "pop" that came from the starboard section of the compartment. I also noticed that I was WAY over temp (engines normally run at 180, gauge was pegged at 240). I don't know if this was a gradual overheat or a sudden one. I wasn't paying as close attention to my gauges as I should have been.
I immediately shut the engines down and opened the compartment hatch. Some steam was swirling around and there was antifreeze in the bilge area. :smt100
With a full complement of passengers on board (some of whom were notorious panickers), I made the executive decision to not investigate further until I had cleared the vessel. I nursed her home on the port engine and tried to hide the inevitable panic of a first-time engine malfunction. We made it in safely, though getting into the slip with only one engine running needs to go on my list of maneuvers to practice.
After everyone said their goodbyes I opened up the engine compartment to survey the damage. The temp gauge still read very high on the starboard engine. I began to suspect the raw water impeller of damage. Not really knowing what else to do, I hooked up my dock hose to the raw water inlet and started to flush the engine. In an effort to possibly diagnose the problem, I cranked the engine. It started up fine, but seemed to be running rough. I also noted a large amount of white steam coming from the exhaust port that smelled like antifreeze. I've had a small amount of white steam coming out of the exhaust on both engines since I bought the boat (August 1), but this was excessive. I shut it down pretty quickly. I continued to monitor the engine temp gauge for the next few hours until it cooled all the way down.
Monday morning bright and early, I set out to check the starboard impeller. I managed to get the water pump off and opened up, to find that the impeller was just fine. Got everything put back into place and tightened with only minor cuts and swearing. I noted that the heat exchanger on the starboard had no coolant visible under the cap, and the overflow tank was empty. I refilled both.
Here's where the real fun starts. :wow: I went to start the engine up and the starter turned over but the engine wasn't making the normal sounds. "Deeper" is how I would describe them. And from what seems to be the center of the engine, I get a loud "knock" sound while the engine is trying to turn over. I didn't hold the key in the ignition position for long enough to see if the knock was repetitive or a one-time thing. :smt089
I enlisted the help of a fellow marina resident who had rebuilt his own MerCruiser last year to come look at my issue. Same thing. Deep sounds, loud knock, no starting. He also noticed a small amount of bubbling coming from the side of my heat exchanger.
:huh:
So I had a local service tech come out this morning to check things out. His off-the-bat diagnosis was a busted head gasket or a cracked head. No solid quote on price to fix. He did note that there did not appear to be any water in the oil, which I take is a good thing. After speaking to his service manager on the phone this afternoon, I walked away with a quote of "at least $1000 if it's the gasket, but it could be a lot more once we get into it." He was pretty clear on a turnaround time of 30 days, and he offered a trailer and tow vehicle to get the 31' x 12' x 11,000lb boat to his shop and back.
I have another local place coming to give me a second opinion (I got two recommendations from my slip neighbors) sometime end of next week. When describing the problem over the phone, the second service tech said that I might be looking at an engine that is simply worn out. This would, I assume, necessitate repowering the boat.
!!!SO!!!
Long story short, my cruising season is over. I still have a very pretty view from my floating deck, and the marina doesn't meter electricity or water. So my lake apartment is still livable.
But I have some decisions to make, and for that I'm enlisting the help of you fine CSR members.
Does a blown head gasket make sense, given the chain of events? What should I be expecting from a cost standpoint?
If I decide to repower with a brand-new 5.7l MerCruiser, do I need to be worried that mixing a new engine and an old engine is a recipe for disaster? That is, should I look to replace both engines in one haul-out-and-take-it-to-a-dealer shot?
On the good side, I ran some numbers today. Given that I was quoted $10,500 for two new drop-in engines with installation, I could replace both and still come in below the NADA Used Boat Value given what I paid for the boat. And I removed the stupid-looking "flying saucer" TV antenna that has been driving me crazy. So there's that.
Evan
----------------------------------------
WELL my RPM issue went on the back burner this weekend. We had the family out on Sunday to check out the boat and have a little Labor Day Weekend celebration. I knew my RPMs weren't acting right but the engines still push the boat ok. We loaded up with people and cruised about 5 miles north of the marina to anchor in a little cove for the afternoon. Good times ensued, everyone loves the new boat. Swimming, eating, sitting in the sun, etc. All around, a great time.
Then we headed back south. Boat was making what I could consider "normal" speed given the history of low WOT and the number of people on board. One of my more astute passengers noted a faint exhaust smell coming from the boat. I (perhaps foolishly) put it off as a symptom of someone who has never been on a boat before. :smt021
I started to hear a small ticking sound that seemed to be coming from the starboard engine. It was very quiet, so much that I at first mistook it for a rattling cotter pin on my pilot bench. I had just recognized the sound as a potential problem when the starboard engine RPMs started to waver. We were cruising at 3200, and the tach showed the engine dipping to 2200 or so. I immediately backed off the throttles.
At that moment, I heard a loud "pop" that came from the starboard section of the compartment. I also noticed that I was WAY over temp (engines normally run at 180, gauge was pegged at 240). I don't know if this was a gradual overheat or a sudden one. I wasn't paying as close attention to my gauges as I should have been.
I immediately shut the engines down and opened the compartment hatch. Some steam was swirling around and there was antifreeze in the bilge area. :smt100
With a full complement of passengers on board (some of whom were notorious panickers), I made the executive decision to not investigate further until I had cleared the vessel. I nursed her home on the port engine and tried to hide the inevitable panic of a first-time engine malfunction. We made it in safely, though getting into the slip with only one engine running needs to go on my list of maneuvers to practice.
After everyone said their goodbyes I opened up the engine compartment to survey the damage. The temp gauge still read very high on the starboard engine. I began to suspect the raw water impeller of damage. Not really knowing what else to do, I hooked up my dock hose to the raw water inlet and started to flush the engine. In an effort to possibly diagnose the problem, I cranked the engine. It started up fine, but seemed to be running rough. I also noted a large amount of white steam coming from the exhaust port that smelled like antifreeze. I've had a small amount of white steam coming out of the exhaust on both engines since I bought the boat (August 1), but this was excessive. I shut it down pretty quickly. I continued to monitor the engine temp gauge for the next few hours until it cooled all the way down.
Monday morning bright and early, I set out to check the starboard impeller. I managed to get the water pump off and opened up, to find that the impeller was just fine. Got everything put back into place and tightened with only minor cuts and swearing. I noted that the heat exchanger on the starboard had no coolant visible under the cap, and the overflow tank was empty. I refilled both.
Here's where the real fun starts. :wow: I went to start the engine up and the starter turned over but the engine wasn't making the normal sounds. "Deeper" is how I would describe them. And from what seems to be the center of the engine, I get a loud "knock" sound while the engine is trying to turn over. I didn't hold the key in the ignition position for long enough to see if the knock was repetitive or a one-time thing. :smt089
I enlisted the help of a fellow marina resident who had rebuilt his own MerCruiser last year to come look at my issue. Same thing. Deep sounds, loud knock, no starting. He also noticed a small amount of bubbling coming from the side of my heat exchanger.
:huh:
So I had a local service tech come out this morning to check things out. His off-the-bat diagnosis was a busted head gasket or a cracked head. No solid quote on price to fix. He did note that there did not appear to be any water in the oil, which I take is a good thing. After speaking to his service manager on the phone this afternoon, I walked away with a quote of "at least $1000 if it's the gasket, but it could be a lot more once we get into it." He was pretty clear on a turnaround time of 30 days, and he offered a trailer and tow vehicle to get the 31' x 12' x 11,000lb boat to his shop and back.
I have another local place coming to give me a second opinion (I got two recommendations from my slip neighbors) sometime end of next week. When describing the problem over the phone, the second service tech said that I might be looking at an engine that is simply worn out. This would, I assume, necessitate repowering the boat.
!!!SO!!!
Long story short, my cruising season is over. I still have a very pretty view from my floating deck, and the marina doesn't meter electricity or water. So my lake apartment is still livable.
But I have some decisions to make, and for that I'm enlisting the help of you fine CSR members.
Does a blown head gasket make sense, given the chain of events? What should I be expecting from a cost standpoint?
If I decide to repower with a brand-new 5.7l MerCruiser, do I need to be worried that mixing a new engine and an old engine is a recipe for disaster? That is, should I look to replace both engines in one haul-out-and-take-it-to-a-dealer shot?
On the good side, I ran some numbers today. Given that I was quoted $10,500 for two new drop-in engines with installation, I could replace both and still come in below the NADA Used Boat Value given what I paid for the boat. And I removed the stupid-looking "flying saucer" TV antenna that has been driving me crazy. So there's that.
Evan
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