I'm in the process of looking @ boats in the 37'+ range and would prefer something with a diesel motor. Just curious to know which motors, if any, to avoid and why???? Im not really interested in flying up and down the Bay or River, more so concerned with reliability and fuel burn
Which Diesel Motor To Avoid
- Thread starter JUMPROPE
- Start date
In before Mr. Webster.
It's not so much which engines to avoid, it's a question of how well the engines have been maintained. A poorly maintained motor can cost well into the 5 digits to make right.
If you are looking for a boat larger than 55' or so, about the only engines I would avoid would be MANs. Not because they are unreliable, but the engines are expensive to maintain, and certified MAN mechanics are scarce.
It's not so much which engines to avoid, it's a question of how well the engines have been maintained. A poorly maintained motor can cost well into the 5 digits to make right.
If you are looking for a boat larger than 55' or so, about the only engines I would avoid would be MANs. Not because they are unreliable, but the engines are expensive to maintain, and certified MAN mechanics are scarce.
- Oct 12, 2006
- 1,974
- Boat Info
- "On Vacation"
2006 40 Sundancer
Raymarine E125 & HD Radar + Garmin 5208
- Engines
- QSB5.9 380 Cummins
My advice would be to stick with Cats or Cummins. Both engines have a track record of reliability and are known to be generally troublefree and efficient (with some minor exceptions esp. CATs before 2002). Have fun shopping for your new diesel boat - it's a very rewarding process once you find the right boat.
Gofirstclass
Well-Known Member
I knew very little about diesels before I bought my boat. The choices from Sea Ray were Detroits or Cats. What I learned was
--Detroits were a lot cheaper to buy, maybe cheaper to maintain but not by a lot, they tend to be noisier and smoke more than the Cats, and they break more often, but when they break they're much less expensive to fix.
--Cats are quieter, don't smoke and don't break as much. But when they do break, get out your wallet b,ecause it's gonna cost you a bundle.
I have Cat 3406C's. What I was told about them when I bought the boat (this from several sources) was that my engines with 1,100 hours was about the equivalent of 11,000 miles on an engine that was designed and built to run 1,000,000 miles in an over the road truck, so they were barely broken in.
I'm crossing my fingers on the repairs!
--Detroits were a lot cheaper to buy, maybe cheaper to maintain but not by a lot, they tend to be noisier and smoke more than the Cats, and they break more often, but when they break they're much less expensive to fix.
--Cats are quieter, don't smoke and don't break as much. But when they do break, get out your wallet b,ecause it's gonna cost you a bundle.
I have Cat 3406C's. What I was told about them when I bought the boat (this from several sources) was that my engines with 1,100 hours was about the equivalent of 11,000 miles on an engine that was designed and built to run 1,000,000 miles in an over the road truck, so they were barely broken in.
I'm crossing my fingers on the repairs!
Found a 1998 400 Sedan Bridge with Cats 3116 with approx 825hrs., one of the motors was rebuilt about 400 hrs ago. Just wanna gather all the info I can and make an informed decision. Any idea what the fuel burn may be for above mentioned boat??
CougarCruiser
Member
Stick with Cummins or Cats. Parts are plentiful, reasonable to maintain, and all are reliable when maintained properly!
FootballFan
Well-Known Member
You didn't mention whether you were looking for new or used.
If used - then condition of the motors are paramount. Engine survey is a must.
When I was going through the process Frank W. was invaluable. His knowledge is deep. Most of what I would type would just be trying to repeat things I learned from him, so will let him fill in the details of evaluating.
One point that I will add, the choice of engines will depend on the model (and in some cases the year) of the boat you select. If you are looking at a specific model, then in a lot of cases the choice of engines has already been made.
For example, we were looking specifically at 47DB's - they are only available with Cummins QSC600.
Mark
Are you flexible on the model to get a specific brand of engine (cat or cummins)?
Going to the Sea Ray website and looking at the specs for model and year will tell you what engine(s) were available for that year.
If used - then condition of the motors are paramount. Engine survey is a must.
When I was going through the process Frank W. was invaluable. His knowledge is deep. Most of what I would type would just be trying to repeat things I learned from him, so will let him fill in the details of evaluating.
One point that I will add, the choice of engines will depend on the model (and in some cases the year) of the boat you select. If you are looking at a specific model, then in a lot of cases the choice of engines has already been made.
For example, we were looking specifically at 47DB's - they are only available with Cummins QSC600.
Mark
Are you flexible on the model to get a specific brand of engine (cat or cummins)?
Going to the Sea Ray website and looking at the specs for model and year will tell you what engine(s) were available for that year.
boltman
Active Member
- Dec 28, 2005
- 1,507
- Boat Info
- 480 Sedan Bridge
"Sea Ray's Best Boat Ever Made"
- Engines
- 700 hp MANS Diesels Thundering Cathedrals of Torque!!
I have a Mans boat , love these engines, they are NOT more expensive to maintain , that is an absolute untrue .... What my oil is more expensive??? No it's not and they are Superior engines for sure. If you're into reliability , buy Man engines , they are right MAN mechanics are scarce they don't have to be near every port or waterway with a semi full of parts , like the others . IMHO
Boltman
Boltman
Yes, we're flexible on model. We started out looking at the 1997-1999 Sundancer 370 and came across Aft Cabins & Sedan Bridges that we really. If we get anything other then the 370 then Diesel motors are a most
BlueYonder
Active Member
I don't know if SeaRay ever used the Yanmar 6LY2A 440 motors. I would avoid this one. I know of several boats including the Formula 40 next to me that had a dropped valve that destroyed the motor. The 6LY2A is not rebuildable if the cylinder wall is damaged.
Gofirstclass
Well-Known Member
Jumprope, in light of what you wrote in post #10, I'd suggest you slooooow down, take a deep breath, then spend some time deciding which style of boat you want. That could easily take a few months. Look at lots of boats, walk around on them, see what you like and don't like about each of the various styles, and then (and only then, not before) should you start looking for a particular brand and model.
My advice is always to buy your second boat first. By that I mean that you should not rush into a boat purchase. Too many people get the hots to buy a boat, find one that they fall in love with it and buy it. They haven't done their homework and end up buying the wrong style of boat. After a year or two they realize it's not what they want or need and decide to trade it in on the one they should have bought first.
That gets VERY expensive and time consuming, so take your time now, avoid the mistake of buying the wrong boat first, and buy your second boat first.
Remember, the wrong boat, even at the best price in the world, is still the wrong boat.
My advice is always to buy your second boat first. By that I mean that you should not rush into a boat purchase. Too many people get the hots to buy a boat, find one that they fall in love with it and buy it. They haven't done their homework and end up buying the wrong style of boat. After a year or two they realize it's not what they want or need and decide to trade it in on the one they should have bought first.
That gets VERY expensive and time consuming, so take your time now, avoid the mistake of buying the wrong boat first, and buy your second boat first.
Remember, the wrong boat, even at the best price in the world, is still the wrong boat.
juggernaut1
Well-Known Member
- Apr 19, 2015
- 1,152
- Boat Info
- Boatless - sold Searay 38 Sundancer
- Engines
- 8.1’s
Yes I've heard the same as Regal boat owners will also attest - although the one in the following link had a failed rod bolt at 343 hours.
http://www.regalownersforum.com/forum/viewtopic.php?f=5&t=6067&start=0
Scary thing is that I was looking at that exact boat to buy which was for sale locally - did some research on the Regal owners club and found it had some "history". Some further research found these Yanmars to be problematic.
Bought the Sea Ray instead.
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MAN,s , CAT,s ,Cummins - i guess every of those manufacturers proudly prooved to build engines lasting tenths thousands of hours in commercial applications all over the globe. i would look more for the whole boat package and a well maintained machinery .
- Oct 6, 2006
- 12,155
- Boat Info
- 1996 450DA
- Engines
- 3116 Caterpillars
Which diesel to avoid..............I'm gonna get in trouble with this one !
First there is some out of date and slightly incorrect information above:
Caterpillar did have some problems with soft block castings and valves, both from trusted vendors, in the late 1990's. Caterpillar warrantied all engines that failed up to about 2004. The important thing to note here is that the engines that failed all did so at about 125 to 150 hours of service. That means that by now the average engine has 75-+ hours on it and is well past the time a failure from those known causes would occur. That isn't to say that poor maintenance or overheating won't cause an engine failure, just that a failure from one of the known causes is highly unlikely.
Detroit Diesel 2 stroke diesels are not cheap to repair any longer. These engines tend to need a top end overhaul at something like 1800 to 2000 hours. There was a time when that could be done for about $1500/cylinder. The 2 stroke Detroit went out of production a long time ago and there are only aftermarket parts available for them now. Repair parts are now pretty high and you can spend $5000-$7500/cylinder on an in-frame rebuild. A viking owner in our marina just spent $78K rebuilding a pair of 6V92's on a 43 Open where he had engine access. A member here on CSR spent $25K+ on a single 6V92 overhaul in a 500DA last year. But, Detroits are tough, work horse diesels that can give years of service as long as you are prepared for a short TBO (time between overhauls) and can afford the parts when that time comes.
Cummins makes good engines, but avoid the 6BTA (300hp) in heavy hulls. Generally this was the engine of choice for Sea ray in the under 40 ft category in the mid - late 90's. However, in boats over about 42 ft, these little guys have a little more than they can handle if you tend to run at higher cruise speeds.
MAN's are great engines, but if you are a new boat owner, you have about a $25K surprise coming at your first MAN scheduled service since it includes a partial tear-down to examine wear patterns in the cylinders. MAN service is also not nearly as available as Cat or Cummins. If you happen to be in an area with a good MAN dealer nearby, then these are great engines, but tell the guy who has to fly MAN technicians or parts in to a location with no MAN dealer that MAN's are not any more expensive to repair than other diesels and you will have an argument on your hands.
Yanmar's? Sea Ray only used them in a few smaller models, so for the OP's question on an older 37+ft boat, Yanmar's aren't a consideration.....but I am not a fan.
Other than the above considerations, Sea Ray only used tried and proven engines so there isn't a particular one to avoid. YOur biggest concern should be figuring out the right boat for you and then being sure that the Cat, Cummins or MAN engines in it have had the proper care and maintenance up till now.
First there is some out of date and slightly incorrect information above:
Caterpillar did have some problems with soft block castings and valves, both from trusted vendors, in the late 1990's. Caterpillar warrantied all engines that failed up to about 2004. The important thing to note here is that the engines that failed all did so at about 125 to 150 hours of service. That means that by now the average engine has 75-+ hours on it and is well past the time a failure from those known causes would occur. That isn't to say that poor maintenance or overheating won't cause an engine failure, just that a failure from one of the known causes is highly unlikely.
Detroit Diesel 2 stroke diesels are not cheap to repair any longer. These engines tend to need a top end overhaul at something like 1800 to 2000 hours. There was a time when that could be done for about $1500/cylinder. The 2 stroke Detroit went out of production a long time ago and there are only aftermarket parts available for them now. Repair parts are now pretty high and you can spend $5000-$7500/cylinder on an in-frame rebuild. A viking owner in our marina just spent $78K rebuilding a pair of 6V92's on a 43 Open where he had engine access. A member here on CSR spent $25K+ on a single 6V92 overhaul in a 500DA last year. But, Detroits are tough, work horse diesels that can give years of service as long as you are prepared for a short TBO (time between overhauls) and can afford the parts when that time comes.
Cummins makes good engines, but avoid the 6BTA (300hp) in heavy hulls. Generally this was the engine of choice for Sea ray in the under 40 ft category in the mid - late 90's. However, in boats over about 42 ft, these little guys have a little more than they can handle if you tend to run at higher cruise speeds.
MAN's are great engines, but if you are a new boat owner, you have about a $25K surprise coming at your first MAN scheduled service since it includes a partial tear-down to examine wear patterns in the cylinders. MAN service is also not nearly as available as Cat or Cummins. If you happen to be in an area with a good MAN dealer nearby, then these are great engines, but tell the guy who has to fly MAN technicians or parts in to a location with no MAN dealer that MAN's are not any more expensive to repair than other diesels and you will have an argument on your hands.
Yanmar's? Sea Ray only used them in a few smaller models, so for the OP's question on an older 37+ft boat, Yanmar's aren't a consideration.....but I am not a fan.
Other than the above considerations, Sea Ray only used tried and proven engines so there isn't a particular one to avoid. YOur biggest concern should be figuring out the right boat for you and then being sure that the Cat, Cummins or MAN engines in it have had the proper care and maintenance up till now.
bahamabreisus
Well-Known Member
- Oct 25, 2007
- 2,555
- Boat Info
- 370 dancer, previous 500,420,390,300 dancers
- Engines
- 454 CI MPI
Not to argue with Frank, but we had 4 cylinder kits and new head installed on our 8V92s a few years ago. Total bill was around $11K, that included valve adjustments on remaining cylinders and the other engine as well. The cause was bad fuel. The work was done by local Detroit dealer. The boats you are looking at, I think will only be available with Cats or Cummings.
dpmulvey
Active Member
- Dec 19, 2007
- 4,188
- Boat Info
- 1999/2007 330 Sundancer Hardtop.
- Engines
- 6.2 Merc Horixons
1.5:1 Velvet Drives
You are relatively new here, so first things first, Welcome Aboard. Now, in my usual fashion, I'll chime in from the opposite side of the coin. Good luck finding a diesel powered 37 in the US. Seriously. Most diesel powered boats that size are in the EU or Asia. Not to say they cannot be had, just hard to find.
In MD, you have roughly an 8 month season if you're really brave and enjoy the cold! Realistically, 6-7 months. If you are going to just putter the Potomac, gas would be a better choice. Gas engines can idle along all day with no problems. Diesels need to be stressed. Too much idle time is not good. I try to think of it in terms of total cost of ownership. Unless you are putting "X" hours on the boat per season, diesels are an annual loss.
There are those who will tell you resale value is better on a diesel. I don't believe that is true at 37 feet. Yes you will pay more upfront to get more in the end with diesels. However if in the end it's a wash in terms of net loss, I see no validity in the argument.
For example:
Assume 100 hours per season.
Assume 1/2 cruise 1/2 on plane for both hence low GPH Figures.
Never owned a diesel boat so I cannot speak to insurance differentials.
Loan Diesel = 700 per month = 8400 annual
Loan Gas = 500 per month = 6000 annual
Slip = 100 per month = 1200 annual
Elec/water = 30 per month = 360 annual
Oil change (D) = 100 every 100 hours = 100 annual
Oil Change (G) = 50 every 100 hours = 50 annual
Fuel (D) = 8 GPH @ 4 per gallon = 3200 annual
Fuel (G) = 12 GPH @ 4 per gallon = 4800 annual
TCO = 13620 (D)
TCO = 12410 (G)
Over all, Gas is cheaper. Diesel mechs are usually more expensive per hour. I can't speak as to the cost of parts that have similar duties like a raw water pump and the like.
If it's about safety, no comparison. Diesel is the only way to go. A fire on a boat is a tragedy anywhere. Diesel will burn but diesel vapors do not explode as readily if at all. I'll leave that to the pros for discussion. Diesel does not produce as much CO as gas so that's a plus.
Long winded but I HTH.
Good luck in your search.
In MD, you have roughly an 8 month season if you're really brave and enjoy the cold! Realistically, 6-7 months. If you are going to just putter the Potomac, gas would be a better choice. Gas engines can idle along all day with no problems. Diesels need to be stressed. Too much idle time is not good. I try to think of it in terms of total cost of ownership. Unless you are putting "X" hours on the boat per season, diesels are an annual loss.
There are those who will tell you resale value is better on a diesel. I don't believe that is true at 37 feet. Yes you will pay more upfront to get more in the end with diesels. However if in the end it's a wash in terms of net loss, I see no validity in the argument.
For example:
Assume 100 hours per season.
Assume 1/2 cruise 1/2 on plane for both hence low GPH Figures.
Never owned a diesel boat so I cannot speak to insurance differentials.
Loan Diesel = 700 per month = 8400 annual
Loan Gas = 500 per month = 6000 annual
Slip = 100 per month = 1200 annual
Elec/water = 30 per month = 360 annual
Oil change (D) = 100 every 100 hours = 100 annual
Oil Change (G) = 50 every 100 hours = 50 annual
Fuel (D) = 8 GPH @ 4 per gallon = 3200 annual
Fuel (G) = 12 GPH @ 4 per gallon = 4800 annual
TCO = 13620 (D)
TCO = 12410 (G)
Over all, Gas is cheaper. Diesel mechs are usually more expensive per hour. I can't speak as to the cost of parts that have similar duties like a raw water pump and the like.
If it's about safety, no comparison. Diesel is the only way to go. A fire on a boat is a tragedy anywhere. Diesel will burn but diesel vapors do not explode as readily if at all. I'll leave that to the pros for discussion. Diesel does not produce as much CO as gas so that's a plus.
Long winded but I HTH.
Good luck in your search.
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bahamabreisus
Well-Known Member
- Oct 25, 2007
- 2,555
- Boat Info
- 370 dancer, previous 500,420,390,300 dancers
- Engines
- 454 CI MPI
I couldn't agree more with DP. Our last boat was a 42DA with 454s. I cant tell you how many times I have said, I wish I still had the 42 with gas. I do understand the safety issues, but things were a lot less expensive with gas. Most of our running is done a low RPMs, which I know is an issue with the diesels. Unless you are planning extended cruising, double think the need for diesel. Our 42 would cruise easily low 20s' top out high 20s
swaterhouse
Well-Known Member
Agreed finding diesel on boats less than 42 is tough especially in the northeast, one of the many reasons we ended up with the 44. Maintenance is higher but the fuel burn is dramatically lower and in many cases the fuel is much cheaper. Where I buy fuel Diesel is at least a dollar cheaper than gas, that may not be the case everywhere but it does happen. Anywhere there is a large commercial marine operation they will have off-highway diesel that doesn't carry as much tax.
Even in DP's example above without potential price per gallon difference, me personally I would 100% pay the extra $1000/year for the added benefits (CO and explosion hazards being forefront). Besides I love the sound of the diesel and the torque output is amazing - super helpful when docking. Drop an engine in gear in a diesel and you feel the movement instantly.
Even in DP's example above without potential price per gallon difference, me personally I would 100% pay the extra $1000/year for the added benefits (CO and explosion hazards being forefront). Besides I love the sound of the diesel and the torque output is amazing - super helpful when docking. Drop an engine in gear in a diesel and you feel the movement instantly.
