Tough start to my season -might need repowering. Thoughts?

luvinlife

Without going into too much detail, the Volvo 5.7 GXI in my 2006 FV 270 has hydrolocked and could have serious damage. The yard is going to pull the engine on Monday and pull the port side head to see what’s up. The engine has a bit over 700 hours on it and had the starboard head fail (and replaced) last year after that side hydrolocked. I’ve mentally prepared myself that repowering is a distinct possibility. Right now I just want it back on the water as the nice weather is here in Rhode Island.

I’m thinking if that’s the case, to look at closed cooling and maybe a 350 mag this time or a 383? I think it will bolt right on. I’m thinking long block rather than crate motor. Thoughts? 

aero3113

@luvinlife , we’re your exhaust manifolds leaking? I would think that’s what caused yours heads to fail.

luvinlife

The yard pulled and inspected the risers prior to launch and validated they were fine. Seems awfully coincidental it hydrolocked on my first trip. The mechanic that pulled and reset them initially thought the gasket failed. There is water in cylinder #3. They ran pressurized water through the engine, bypassing the hoses and water poured out of the cylinder. They said it could possibly be the head or block but it was not the gasket.  I’m not convinced the riser gasket was not the culprit. 

aero3113

The risers can be fine and still have a leaking exhaust manifold. It happened to me last season. 

luvinlife

That’s what I think happened, the gasket was improperly installed or defective. Hard to really know or prove though.

aero3113

Your exhaust manifold could be corroded allowing water into the cylinder. Not just the gasket.

luvinlife

I had them inspect the exhaust manifolds and risers as a preventative measure prior to launch and they said they were fine. Replaced in 2017. 

PickleRick

Even new manifolds risers from oem manufacturer need to be double checked with ba$**** file or at least straight edge before install.  Im not familiar with volvo but mercrusier oem needs checked.  I put a new set on my 235 before selling at nearly 900 bucks they were not 100% true.  The oem riser gasket may have been thick enough to seal but I wasn't going to roll the dice as I had the time to true the mating surfaces.  

I have no experience with the 383 but the guys on the marine engine forum swear by them in small block applications.  More torque means maintaining same cruise speed as old motor but at a lower rpms.  This can result in less fuel used.  The 383 is identical to the 350 as same block/heads/accessories are all the same.



I personally think boats over 26 ft deserve a big block! 

Not sure if you've gotten any quotes yet but Michigan motors (maybe with a z) has a stellar reputation for new and reman chevy blocks from short blocks to drop in packages.  


My manifolds and risers were replaced as premaintance, still sold for 100 bucks locally.

skuter99

If I were swapping motors I would definitely go for the stroker 383 over the mag 350

luvinlife

Thanks. I’ll strongly consider that! 

J3ff

volvo to merc? Dont know that I would do that after seeing how crappy merc "quality" is.. 

Michael T

Agree with @PickleRick regarding his big block comment. @luvinlife if a big block is not in your future I highly recommend the 383. I had a 383 in a Rinker (pictures have been posted on here several times) and as @PickleRick stated their torque curve line would be a game changer for your boat a REFRESHER for sure!.

Aqua_Aura

I have said it before but I originally wanted a Merc however now owning a Volvo and seeing the issues with Merc I am very happy. 

69fastback

Did it hydrolock while you were moving across the water, or did you try to start it and it was hydrolocked?  

Also, a 383 won’t let you cruise at the same speed and lower RPMs. It’s a mechanical ratio. A certain amount of engine RPMs equates to the prop turning a certain RPM, which pushes the boat the same speed. That doesn’t change unless you change gearing, regardless of the power. 

Aqua_Aura

Wouldn't the 383 have more torque allowing for a bigger prop pitch thus allowing the boat to move quicker in the water for the same given RPM?

69fastback

Aqua_Aura said:

Wouldn't the 383 have more torque allowing for a bigger prop pitch thus allowing the boat to move quicker in the water for the same given RPM?

Sure, if you change the prop pitch. 

Aqua_Aura

I guess I was assuming that would be done. If you didn't then you would probably over rev the engine. 

PickleRick

But small block chevy motors sound cool above 5500 rpms!!

J3ff

I have been trying to find someone with 24p blades on their 383 270 to compare my 22p with, but so far have had no luck. I feel like the boat is under propped.. with a 383 and 22's

RiverRat232

I would love to see someone drop a couple of these in a cruiser.
https://www.mercuryracing.com/engines/sterndrives/dual-calibration-15501350.html

Aqua_Aura

That would be nice especially since you can turn them down to 1350HP for that pleasure cruise experience 🤣

PickleRick

Using the pleasure key fob for inexperienced guests on the boat sounds almost as bad as the old Johnson outboard commercials

RiverRat232

Aqua_Aura said:

That would be nice especially since you can turn them down to 1350HP for that pleasure cruise experience 🤣

2700 HP of "pleasure cruising" 

oscar1

I will pick the new 6.2 liter 350hp over any other motor today.

Michael T

Not over a 383.

luvinlife

Don’t think the 6.2 is a clean swap with the outdrive

Black_Diamond

Lucky that 112 octane fuel needed is only $14/GALLON. 🤑🤑🤑🤑🤑

Warranty:

10 Hour Warranty At The 1550 Power Level (At 2000 RPM Or Above) Or 1 Year, Whichever Comes First.