Detroit 6V92 DDECs

[Bertramp]

I have been offered a pair at a pretty good price that has 2000 hrs.
They are running takeouts that have already been removed.
I believe the rating to be 575HP

I have a series one 45C with Cummins 370s.

1. Approximately what should I expect an install cost .... (I know that I will need new shafts and props too) ?

2. What kind of performance would I get ..... and how much more fuel will I be burning ?

3. I've heard that they are good on fuel, will I get a better mpg ratio ?

thanks

 

[post42]

Bertramp, why are you thinking of changing your engines? I looked at that boat before you purchased it and as I remember the engines sounded pretty good. Just wondering, Chris.
________
Bmw m44 history

 

[SKYCHENEY]

If those have 2000hrs, they are probably ready for rebuild. My 6v92's are only 465 and have 3300hrs, but I doubt at the 575 rating they would hold up much more than 2000hrs.

It may make more sense to buy new engines to repower with.

 

[Genesis]

I wouldn't own DDECs at any price. If you're going to go with an electronic engine you want a modern one....

 

[DLCameron2]

These engines are probably worn out as Sky noted above, at that power rating some people call them grenades. Why not research a new pair of engines like Cummins or Yanmar? Cummins will have an ISL with a 500+ rating all new technology etc., Yanmar's highest rated engine is built by Scania and also is I am sure a quality piece. It will cost a lot to retrofit all of the electronics to your boat.......I would think new is better and much lower risk.

Why go thru all of the effort and end up with someone else's used problems?

DC

 

[SKYCHENEY]

I wouldn't own DDECs at any price. If you're going to go with an electronic engine you want a modern one....

Now that most of our truck engines are electronic, oh how we long for the days of the old mechanical diesel. Now if a sensor or wire goes bad, we have to call the tow truck. It used to be you just had to make sure it got fuel and air and it would run. I know the new engines are quiet and fuel efficient and they don't put out the amount of emissions that the old one's did, but they are expensive to operate too.

I would and am sticking with my old mechanical diesels in my boat. I don't think you can improve on that from a reliability standpoint. They'll always get you home, even if they're sick.

 

[Genesis]

Yeah, its kinda fun trying to call the "tow truck" when you're 100 miles offshore fishing........

 

[nor'easter]

I run them at 565 hp, 1995 DDEC 6V92s 2350 rpm in my 39 SX WOT under a full load. I cruise b/w 1650 at 17kts (35 gph) and 1850 at 23kts (42gph). 1600 hrs so far, 225 in last 19 months since I bought the boat and they run great. I use block heaters most AMs unless warm in the summer, they have grey/white smoke for 30 secs and clears. No smoke during operation. They get oil and filters every 100 hrs. The DDEC edm gives great monitoring of functions. The low idle is great for close quarters maneuvering, as it dropr rpms to 400 per side, and makes it easier and less touchy getting in to tight spaces.
I had one electrical glitch with stb transmission and would lose control briefly trying to shift from neutral. It was a pain, and it turned out to be a poor connection, but it was hard to find the cause.
I have similar impressions of these engines rated at the edge of the hp/disp curve, but they have treated me well. I also treat them well.

 

[Bertramp]

thanks folks .....
It sounds like this falls under the category of "the devil you know vs. the devil you don't" ..... I think I'll be content with my "oldies" ...... and stash the cash for new engines when needed.

 

[nor'easter]

Even though mine have run well for the short time I have owned them, I am sure that I wouldn't pick to repower with them. I think there is too much experience out there to ingore, IMHO. I started a thread a ways back on a repower of my boat the change out the 92s, but have decided to sell and move up because our boat doesn't have the accomodations for 2+ couples to cruise comfortably when I am not fishing.

 

[Captcoop]

I am not suggesting that you make the change but I had an offer much like you have and did some checking into the swap. The engines that were offered in my case did not include the computer control and at the time Detroit quoted the unit at about $40,000.00. I would make sure that you have a complete system. Good Luck

 

[Fanfare]

When I was repowering in 1993 or 94 I had the choice of 6-92TA in DDEC or mechanical. I finally opted for the old reliable that I knew how to fix. It turned out to be the correct decision. DDEC went through three different revisions before finally scrapping the concept. I wish it had worked because then our old Detroits would still be in production, but it was not to be. I figure that if Roger Penske couldn't make it work then nobody could.

 

[Genesis]

What ultimately killed Detroits was the EPA.

But - there's no escaping the fuel efficiency issue. Detroits will always lose to a 4-stroke in that department, simply because of the need for the blower. It eats horsepower and is always there, always on, and always costing you fuel.

Don't get me wrong - I love my Detroits. But if they ever have to come out of the boat for some reason, either the same engines will go back in or I will repower with something more modern - if I'm going to take the hit going electronic, with all that entails, I want the rest of the benefits as well.

 

[Maynard Rupp]

Karl, we used those blowers as supercharges on fuel dragsters. We tightened up the clearence between the beaters and the lower case, used after market tougher end plates, and overdrive the thing about 40%. We made some awesome horsepower for about 7 seconds. Those engines would do 3000 hp. with 400 cu.in. Nowdays they meke about 6000. Same old rule as diesels though. If you want more horsepower throw in more fuel and more air. Our nitromethane mix would run at a 1.8 to 1 ratio with air. A gasoline engine ratio is 13 to 1. We used about 1 gallon per second. They double that now and pay about $70.00 per gallon. And you thought Gigabite chews up fuel.

 

[Genesis]

Yep..... but there's no denying the parasitic robbery that those things consume. They're amazing devices those blowers, but there's a LOT of power being chewed up driving them - and that's fuel that you pay for but it don't move the boat.....

That's a big part of why the Detroits can never hit the numbers on fuel economy of the newer common-rail engines. I'm simply AMAZED at some of the reports I've gotten from people - things like 32gph at 25kts out of the 45C with the Cummins QSMs - and the QSLs are supposed to be even better!

For comparison, I burn 36gph at 18 kts with the Detroits..... that's a FORTY PERCENT difference in burn - and at a higher speed. I can do 25kts (in the corner) but I don't even look at the Floscans when I do WOT RPM tests.....

 

[jim rosenthal]

One of our members had a repower done last year by Jarrett Bay- new QSM11s into his 80s 45C, the newer hard-chine design. Impressively fast, economical, and he hadn't even finished dialing in the props when I saw it. If you ask me Cummins is pretty much the name to beat these days...folks doing open-checkbook updates are picing those engines. Luggers are also good, but for every ADA dealer there are probably ten Cummins dealers or more.

 

[REBrueckner]

A lot of speed and fuel consumption claims I hear elsewhere are crapola. I'm not suggesting newer engines don't get better fuel efficiency, clearly they do, but many claims must be taken with a grain of salt, especially when buying somebody elses boat!! One of the great things about this forum is that discussions are factual rather than "wishful".

 

[Genesis]

That's true..... I have floscans, so there's no hiding the truth from me...

 

[Bertramp]

I always wondered with flo-scans on diesels ... do they show the flow to engine or the net of flow to engine and the return ?

 

[Genesis]

There's two sensors - one for forward, one for return - they subtract off the return....