New engines- Good buy or disaster?

strick · **Posted:** Thu Aug 29, 2013 2:12 pm

Here's a fun one... Hoping some of the mechanically inclined members have some feedback. I'm looking to buy a V318 or V338. Seller (nice an cooperative guy) has 2006 V318 with brand new Merc 350 engines. His story goes that this summer his 275 hr boat blew a starboard engine as a result of water in the gas. Replaced the engine as an insurance claim, and not trusting the port engine since it had been sucking the same gas, voluntarily spent the dough to replace that one as well. New engines are GM, not a knockoff brand. They have a 1 year warranty. all new risers and exhaust parts. These statements were verified in a conversation with the marina that did the work. He's selling the boat now with 5 hours on it (which seemed odd to me since he just sunk all that money into it) in order to do some land traveling, supposedly. Pictures look very clean. Outdrives are the original ones with 275 hours on them. SO.... what do you think? Should this boat be considered? Or, is it a nightmare waiting for a new owner?

jsimon · **Posted:** Thu Aug 29, 2013 2:36 pm

Well... my take,

if there are reciepts to back up the story, and the survey and sea trial go well, then maybe, but

I dont like the 06 model year (not knocking anyone that has one) becuase of the puzzle steps, the tv in the galley cabinet and no folding arch.

These items may be able to be overlooked if the price is right, but at least be aware

Good luck in your desicion

rpengr · **Posted:** Thu Aug 29, 2013 3:06 pm

I don't know why "water in the gas" would blow an engine. But a rusted exhaust manifold/riser could allow water in the engine. Either way, replacement engines would fix it.

GM does not make gasoline marine engines per se... some other company takes a GM engine and converts it into a marine engine (including Volvo, Mercury, and many aftermarket companies). Aftermarket companies either convert a new engine, or a used engine is rebuilt and converted. So what company did the "new" engines come from? I would find out so you can search for what their reputation is. There is a couple companies out there that are not reputable.

You will want to know if all the engine components new (starter, intake, distributor, alternator, etc)?

Are there any signs that the boat was flooded/sunk?

It does sound like a strange story. Maybe he is disappointed in the performance compared to how it ran before? Maybe spending all that money made him loose interest in further boating?

LouC · **Posted:** Thu Aug 29, 2013 3:30 pm

I agree it does seem odd, engines don't blow because of water in the gas but of course if you get water in a cylinder you can bend a rod due to hydrolocking. And after all that expense, he is selling it...One thing to ask about is who provided the engines, are they really NEW as in new block+heads+internal parts and manifolds, or are they re-man engines? There is a big difference. Ask to see receipts for everything.

firecadet613 · **Posted:** Thu Aug 29, 2013 3:47 pm

Water in the gas will not make it past the cool fuel module. I had this issue on my sea trial, and the motors wouldn't run until we fixed the water in the fuel issue.

I don't buy this story. Who in the right mind spends that much cash to replace an engine that doesn't need it?

PM me if you need more details about the water in the fuel or the cool fuel system.

ric · **Posted:** Thu Aug 29, 2013 5:14 pm

Water in gas doesn't hurt an engine, ever. It can hurt a fuel system, but we're talking about usually a fuel pump and or injectors/carb rebuild needed.

There is no such thing as a marine engine. The longblock in your boat is a standard automotive engine with some boat parts bolted onto it (intake manifold, carb, ignition, exhaust, accessories, etc). Please, leave the wives tales out of this.

I would look into if the boat was sunk/hurricane boat.

strick · **Posted:** Thu Aug 29, 2013 5:18 pm

Thanks for the input so far! Will inquire about receipts & who provided the engine. Said they are "new, mercruiser brand engines, not remanufactured". The mechanic at the marina that did the work said (and forgive me if I get the terms wrong) it was improper (premature?) detonation which blew out the crankcase and bent the piston in the engine. Basically destroyed the engine and spilled oil in the bilge, but did not cause any damage to the hull / integrity of the boat. He said that normally the engine electronics would alter the operation of the engine to adjust for that, but the boat was being operated at WOT & that is why it blew. Again, I am an investment advisor not a mechanic by trade, so my I am relying on my somewhat limited engine knowledge here...

ric · **Posted:** Thu Aug 29, 2013 6:26 pm

Both ethanol and water are octane boosters, they squash detonation and both systems are used in forced induction cars and trucks. It's virtually impossible to explode a non-forced induction engine due to detonation. It would have to be severe detonation over a long time (bad injector) and even then it would just burn a piston/rings and you'd notice the smoke and lack of power. Bend rods and holes in the block sound like it sucked in water from an exhaust manifold or an oil pump failure or something nutty. Either way, it's got new engines now.

If they just replaced the block (usually) I'd definitely check the plugs for signs of lean burning on a piston.

rpengr · **Posted:** Thu Aug 29, 2013 9:35 pm

ric wrote:

There is no such thing as a marine engine. The longblock in your boat is a standard automotive engine with some boat parts bolted onto it (intake manifold, carb, ignition, exhaust, accessories, etc). Please, leave the wives tales out of this.

Ric,
If you're referring to my comment, then you need to read it more carefully. I was pointing out that although GM crate engines are used, it is another company that is the builder. The 1 year warranty would come from the builder, not from GM. And as you have pointed out, the builder even selects the camshaft.

If the replacement engines are Mercruiser, then that is great!

Maybe he was disappointed to find out that it is not recommended to run around at full throttle all the time.

ric · **Posted:** Thu Aug 29, 2013 10:32 pm

You an drive around at full throttle all day every day. If you can afford a new engine yearly.

88Liberator261 · **Posted:** Fri Aug 30, 2013 3:45 am

As for the original post - for those of us who buy used cars trucks bikes boats what-have-you there are things some can accept and others rule out immediately - different for each individual based on things such as condition, history, price, mechanical ability, number of times you were burnt (or not), or wanting something that is as close as possile to stock....

It takes alot of questions/answers to overcome a suspicion that an altered/repaired vehicle is being represented correctly - hell - that an "unaltered" item is legit. If there isn't a significant reason (a big price reduction) to purchase this boat then I would most likely keep looking for one with less of a story. However, for such a big purchase an independent survey by a reputable company would be the only way to sort this out.

Off topic - can't say I completely agree with Ric's over-simplification of marine engines. Marine engines can be build with different bearing tolerances, different ring gaps, improved oil flow, which are done for reasons relating to the loads the motors see in boating (including more time at WOT), or the cooling system used...in addition to the bolt on parts you mention. These engines are "built" for marine applications and they are better suited because of it, therefore they are called marine engines...nothing to do with the "original long block". I suppose it's just a different way to apply a definition. Just my $.02.

ric · **Posted:** Fri Aug 30, 2013 6:22 am

88Liberator261 wrote:

Off topic - can't say I completely agree with Ric's over-simplification of marine engines. Marine engines can be build with different bearing tolerances, different ring gaps, improved oil flow, which are done for reasons relating to the loads the motors see in boating (including more time at WOT), or the cooling system used...in addition to the bolt on parts you mention. These engines are "built" for marine applications and they are better suited because of it, therefore they are called marine engines...nothing to do with the "original long block". I suppose it's just a different way to apply a definition. Just my $.02.

They're not. It's spec for spec exactly no different than a standard automotive longblock. The longblock includes the block, crank, rods, pistons, rings, bearings, heads, valves, valve springs, etc. Mercruiser and Volvo are known for swapping out cams to lower HP so they can sell different engine packages.

rpengr · **Posted:** Fri Aug 30, 2013 7:59 am

strick wrote:

Thanks for the input so far! Will inquire about receipts & who provided the engine. Said they are "new, mercruiser brand engines, not remanufactured". The mechanic at the marina that did the work said (and forgive me if I get the terms wrong) it was improper (premature?) detonation which blew out the crankcase and bent the piston in the engine. Basically destroyed the engine and spilled oil in the bilge, but did not cause any damage to the hull / integrity of the boat. He said that normally the engine electronics would alter the operation of the engine to adjust for that, but the boat was being operated at WOT & that is why it blew. Again, I am an investment advisor not a mechanic by trade, so my I am relying on my somewhat limited engine knowledge here...

Hi strick,
Looking forward to hearing more. If these are brand new Mercruiser engines, properly installed, then you probably have something very good there. Especially if they can get the warranty transferred to you.

This is a big purchase, so paying for a marine surveyor (at your expense) would be well worth it... either before you make an offer, or a satisfactory survey as a condition of your offer/contract.

www.iFourWinns.com

New engines- Good buy or disaster?

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