550 with 6v92 DDEC

[mquiet]

Can I get the good the bad the ugly. Engines have 1600 hours. They seem to be well maintained. The DDEC controller was just upgraded in 2013. Listing has 1250 horses, but Searay did not make this, so I would have to assume they meant each engine is rated at 606hp. I do appreciate the help. I am trying to work between the Cat 3196 with the Aftercooler issues and these with being too small an engine for the weight of the 550.

 

[dcpringle]

I've heard that the DDEC are louder than the Cats when running, but i don't know this first hand.... I'd be looking at availability of parts and service in your area. I know with Cats, they have a large network for both.

 

[All's Well]

You may want to call Dwayne Dehart and get his opinion (910) 452-7878. Dwayne is President at Bell Hart marine and he was the best tech that Marine Max had a decade ago, he's very familiar with the Sea Ray line.

 

[fwebster]

Actually, the 6V92 powered 550DB is a very good performer. It is a big heavy boat, but the 2 stroke Detroits are big torque engines and they handle the 55 very well. The 55 has big wheels and moves a lot of water and is pretty intimidating in tight spots until you get the hang of anticipating the boat and thinking ahead of her. Sea Ray has incorporated a cool design idea into the 55…….the wetted part of the hull stops about 3 feet short of the transom, so you have a 55 ft boat with a lot less than a 55 ft. wetted hull when she is hooked up and running.

Detroits are 2 stroke engines so, for every revolution, they have 2X as many combustion strokes as a 4 stroke engine. You can expect them to be loud, smokey and leak a lot more oil than the Cat comparison.

The biggest concern a shopper should have with 6V92's is that they stopped producing the 2 stroke engines years ago. Due to the 2 stroke design, the top end tends to wear quickly so an in-frame top end overhaul at 1500-2000 hours is common place. When Detroit Diesel was in production on the 2 stoke engines, a top end rebuild cost about $1500/cylinder………or about $9K per engine for a 6V92. Since parts are much more scarce and there is no factory supply, everything must come from the aftermarket and the parts today can run $7500-$8500 per cylinder. So, a top end, when you need it, can run $40-$50,000 if you don't cut any corners on machine work, parts replacement etc.

Detroits have been know to be dependable work horses. I personally don't find the added noise or smoke objectionable…………I have run a 55DB for our dealer a number of times and help a friend with a 54 Hat and a 43 Viking Open that are Detroit powered. My biggest issue with Detroits is that the prospect of a rebuild at less than 2000 hours adds a sizable layer of risk to an already expensive purchase.

 

[Skybolt]

Very nice post Frank.
Here's my 2 cents, I have 6v92 low profiles with the 9225 injectors. That means twin turbo's but running @ 475hp vs. the DDEC @ 550-600hp.

The DDEC had different types of injectors, according to my research over at Boat Diesel. From everything I have read rebuilds occur at 1K-2K hrs. You need to pull the inspection plates and see how much cross hatch is left and if the pistons show signs of over heating. If that all looks good the your ok for a while.

As for the power they provide, no problem there. MY boat when it was pulled this year was 34K lbs. I run a solid 20knts @ 1850rpm. 24knts @ 2000-2100 rpm, depending on the seas. WOT ~27knts. - absolutely crazy for a that type of boat. IMO. I am swinging 26x28's 3 bladed.

As Frank states they are loud, but the smoking should not be there unless something is wrong. The 71 series will smoke out a parking lot and still be fine. But the 92 series should not do that. They do spill some oil though, just the nature of the beast as Frank pointed out. My engines have dual Airseps which help a lot. But monthly cleaning is definitely needed, depending on use and how hard they are ran.

I love Detroit's, always have. They sound awesome, like they mean business. I grew up with Cat's and Detroit's so I am a little biased. I don't think you can go wrong with Cats myself. Just know they al have their issues. DDEC's tend to not last as long though.

 

[mquiet]

Thanks for the insight. It is helping with my decision making process


Sent from my iPhone using Tapatalk

 

[Gofirstclass]

My 550 has Cat 3406C's.

Before I bought it I was doing the homework on this particular boat and called SR about the engines. I was not at all familiar with diesels so made sure the guy I was talking with knew that. He said the comparison between the Cats and Detroits went like this--the Detroits smoke more, are louder, vibrate more and break more frequently. But he countered that with the fact that there are (at that time, 2010) parts for them just about everywhere in the world so the parts were relatively inexpensive to buy and repair costs on the engines would be lower than on a Cat.

The Cats, while they're more expensive to buy parts for and to repair, don't break nearly as often, run quieter, don't smoke and tend to be a preferred engine.

My experience with my boat is that the engines smoke for about the first 2-3 minutes then the smoke stops once they warm up just a tiny bit.

My myself, I'd pay a lot more attention to what Frank wrote about parts availability and costs to repair than what I wrote. He's the expert, I'm just a boater.

 

[mquiet]

GFC, you are spot on. I take what Frank always says very thoughtfully. I have talked with him in the past and he is very knowledgable. I have moved on from the DDEC's and continue forward. Thanks everyone.

 

[xravenx]

This thread reminded me that I have six (6) cylinder kits (p/n H23514261) new & unused in unopened boxes if anyone is interested. The cheapest I saw on ebay was $210.oo per kit. Been meaning to advertise them, kind of forgot about them.

John

 

[Skybolt]

This thread reminded me that I have six (6) cylinder kits (p/n H23514261) new & unused in unopened boxes if anyone is interested. The cheapest I saw on ebay was $210.oo per kit. Been meaning to advertise them, kind of forgot about them.

John

$135 Here , there are a lot for ~199 as well.