Cobaltchat.com

Hi All,

I was out for a fall ride in my new 2023 Cobalt R6 Surf, enjoying the day when the engine suddenly cut out—so far, only 20 hours on it! No weird sounds, no alarms. I tried to restart it, and it wouldn’t turn over. I opened the engine compartment, and it was definitely hot in there, though there were no warning lights on the dash before it died. I was distracted by the strong wind and how close I was drifting to shore, so I didn't check the engine temperature gauge. Instead, I focused on calling for assistance before I ended up on the rocks.

Here is the dealers report:

We are still working away on the R6. We have been in touch with Volvo and sent them all of the info they require to move forward.

There are no counts of an overheat stored on the engine, however the port exhaust manifold paint shows signs of being extremely hot and we believe it has cracked internally causing the engine to hydrolock which is what you experienced when the boat shut down on you. You also did mention how hot it got.

Again, no sign of why it may have overheated as the impeller itself is still in perfect condition, coolant level is up to spec, and everything with the cooling system checks out.

I told them that repairing the engine was not an option under any circumstances. There will be damage that might not become apparent until later on. They need to simply install a new engine. Is that a reasonable request?

Mike

Seems like it might be a reasonable ask based on what we know so far. It's a good sign that the dealer said it's clear it got very hot - they seem to be on your side. I suspect they will find something missed during construction once they start digging deeper, and the cause will become apparent. Please do keep us posted on how things progress!

Thank you for the reply. I'll update you here as I learn more.

I'm no expert mechanic, but here is what I do know:

I've seen engines overheat and to the point of paint bubbling that is HOT -- that engine is done. It may run, but over the long haul you will have problems. A new engine at this point is the only good solution.

Who knows why it overheated, but what likely hydro locked it is when the engine shutdown, the excessive heat in the exhausted system caused it to literally siphon water back through the exhaust. Hydro locking is the major problem, but the cold water coming into the hot exhaust and cylinders probably did just as much damage.

The good news is dropping a new engine in that boat is easy / costly, but easy. It will not be detectable from factory. Hopefully this is what VP/Cobalt do for you.

Keep us posted.

Our Dealer was commissioning a new Cobalt ( not ours) and on sea trial engine let go cracking the block Catastrophic failure like yours. I spoke with the disappointed owner and he explained without any hesitation the dealer pulled an engine out of a new cobalt that was the same and put it in the new owners boat. Delayed delivery by two days. Never a problem at our dealership they make certain you are satisfied !

Thank you for the replies - I'll update when I hear more

First- that totally sucks. I hope they stand behind it. Hard to remember in the heat of the moment, but next time you find yourself drifting towards shore, you can always toss an anchor out until you can readily assess the situation. I learned that many years ago and always have an anchor ready to deploy. I can usually throw one out in less than 60 seconds if need be.

I just received notice that Volvo is replacing the entire block and manifolds under warranty! Great news. They still do not have a good explanation as to why there was an overheat with no warnings and what exactly happened...

Glad you got a good resolution to it, and the team of people behind the boat made it right. Thanks for reporting back!

Yes thanks for the update,mjc…
Great news.

Glad that Volvo is taking care of it. We had our lower unit fail on our 2018 R5 Surf last June. My daughter was driving it at 6mph in 40 feet of water when it just stopped. I didn’t 100% believe her at first but there were zero nicks in the props when we pulled it out at the repair shop on the lake.

This is some of what they found when they took the lower unit apart. It was like a milkshake with metal when they opened it up so clearly water had gotten in the lower unit. The props had hit bottom hard enough a couple of summers earlier to bend the prop shaft so likely a seal got damaged and was letting water in.

The new lower unit was $14.5k plus shipping and another $1,500 in labor.

The good news is had it all back in the water 3 days later and we put another 185 hours trouble-free hours on it the remainder of the summer.

Am thinking about moving up from A28 to an R8 surf, but these threads on catastrophic failures on Volvo powered surf boats is making me nervous. How common of a problem is this?