Mainship 40 SB vs. Bayliner 3888

"Friction causes additional fuel burn... anytime you change direction of the thrust you add friction."

If you were to turn 15% of the hp into friction in this case that would equate to about 15+ hp being wasted as heat. At 2,544 btu per hp that comes out to over 38,000 BTU's of waste heat alone at a cruising speed which is quite an impossibility with the gear coolers supplied. Please point out some manufacturers specs showing that the V-drive will absorb 15% more than the typical 3-6% typically spec'd on each transmission I am aware of.

"The bridge can collapse the window system. See the Whidbey island accident. The Captain got scared, panicked and missed the inlet. The damage tells the story... IMO"

A boat is traveling in very heavy seas and hits a rock jetty real hard - this opens up a hole which totally sinks the boat is same rough seas at that jetty. The boat was submerged and 'banging' off the bottom for days until a dive crew could attach straps to 'some lifting points' to raise the totaled boat. When it was retrieved the photo taken shows that the fly bridge was collapsed.
Does this represent your total inputs on coming to the conclusion that the fly bridge is an issue with these boats?

Hope this helps
 
7.5% on each change of direction per my training instructor at the factory training school I attended. Add the poor weight distribution of a v-drive boat and then add the shaft angle required for v-drives and you'll find the other 7.5%. straight shaft 0, outboard (1 90 degree angle) 7.5% loss. Stern drive (2/ 90 degree angles 15% loss)Go ahead and argue all you want I learned from an expert... not boatered.

Yes, the Bayliner bridge structure sits on top of an aluminum frame, just look at it, which is supported with window glass. As for the collapse of the bridge... read the accident report. Hummm, well the boat that has a more modern hull and deck design, same builder, hit same rock with much different results.
 
"7.5% on each change of direction per my training instructor at the factory training school I attended. Add the poor weight distribution of a v-drive boat and then add the shaft angle required for v-drives and you'll find the other 7.5%. straight shaft 0, outboard (1 90 degree angle) 7.5% loss. Stern drive (2/ 90 degree angles 15% loss)Go ahead and argue all you want I learned from an expert... not boatered.

Yes, the Bayliner bridge structure sits on top of an aluminum frame, just look at it, which is supported with window glass. As for the collapse of the bridge... read the accident report. Hummm, well the boat that has a more modern hull and deck design, same builder, hit same rock with much different results."

Thank you for the response - It allows me to correctly file it for future use.

Hope this helps
 
Yes, there is a loss of energy in a gear box. The 7½ % is not reasonable in this case. Your using over 100 hp to get a 20,000 # boat running on plane. That would be 7½ hp or about 5 kW or energy heating that "direction changer". That would smoke your engine room. These transmissions are not water cooled.

That much energy loss does not stand to reason.
 
Normal loss through a gearbox is 1 to 2%. That's gears not automatic.

"Direct" drives (inboard) go through one gearbox the same as a Vee drive. One transmission. This is necessary to reduce the propeller speed from the much higher engine speed. Whatever the loss, your talking one gear change for either system.
 
"Yes, there is a loss of energy in a gear box. The 7½ % is not reasonable in this case. Your using over 100 hp to get a 20,000 # boat running on plane. That would be 7½ hp or about 5 kW or energy heating that "direction changer". That would smoke your engine room. These transmissions are not water cooled."

Hello RB - Thanks for the data on transmissions and parasitic losses. I am sorry to have to inform you that you were risking your life when you took your 38 Bayliner up and down the east coast with that fly bridge - just as we did with our 38. If your were out in very rough seas of 6' or more following a Maxum and hit the exact same rock that the Maxum did your fly bridge could have collapsed as a result of that hit.
I consider us very lucky boaters indeed.

Hope this helps
 
Smitty477 you should know...Your gear is equipped with an oil cooler that has seawater running through it as to prevent your engine room from smoking.

Risking life... drama queen? Yes, I would recommend the Bayliner 38 for east coast boaters who recreate less than 6' seas, but never, ever follow a maxum.
 
Back on point guys. The OP asked a legit question. The rest can go to NBR.
 
"Back on point guys. The OP asked a legit question. The rest can go to NBR."

David - excellent point which I agree with. I do not know RB but I have seen 100's of his other posts on a few other sites. Neither myself or RB currently own a 38 Bayliner but we each have had one that was cruised extensively (easily over 10,000 miles between us)as has most of the other 1,000+ 38's that were produced.
So we are in a pretty good position to answer questions about that boat and/or send the OP over to the BOC where there are many other current users out there. I have also cruised many number of miles with a gas version of that 40 Mainship so I can offer some information about that boats cruising manners as well as its fuel burn. Because the OP asked some specific questions I was able to answer them (such as parts or engine issues) in a more valuable way. At the same time the OP appears to be looking for factual answers so issues such as V drive efficiencies/friction are fair questions. I think it would be great if anyone could post any manufacturer or factual data on the V drive parasitic hp drain as that would help. The Mainship is heavier with a deeper V which costs fuel efficiency and the 38 Bayliner has prop pockets which help in shaft angles but disrupt clear water flow and I do not know the running shaft angles on the Mainship with its V drive.
I can say without a doubt that the 38 Bayliner with 175 Hino's will consistently get between 1.2-1.4 nmpg in neutral seas in the area of 14-15 knots as one cruising example. At hull speeds at or below 5 knots the boat will reach about 4nmpg and at say 7 knots you will be in the area of 2.5 nmpg exact numbers being very speed sensitive.

Thanks - and hope this helps
 
The Bayliner 3988 is the boat I'd recommend you consider. Most of them are powered with Cummins engines. The factory knew the design deficiencies in the 38 and improved the boat considerably in the new model. Personal opinion, I've owned both types... stay away from v-drives if you are seriously considering long range travel. It's a compromised design for the propulsion system and hull, which is fine in some applications. Think about it... I don't see many sport fishing inboards running v-drives rare in commercial applications too. You'll find v-drives common on floating condos, aft cabins, and express designs, because the trade off is deemed worth it by the buyers. The center of gravity has a huge effect on how a boat handles in open seas; keeping it low and near the center of the vessel is the goal and so straight shafts inboards have a significant benefit beyond the efficiency question.

I have had plenty of time running a 38 Bayliner, but will never own one, and I can say they are wet boats, green water on the deck and house, so the rise of the bow while underway in combination with helm position causes the lower station to become worthless for rough water navigation. Also, I would never recommend buying a 3888 unless it has Hinos. Don't even think about it! FYI Most boats are not of a pedigree worthy of spending money to repowering. IMO
 
If considering Cummins 6b engines please visit Tony Athens site at smbar(dot)com to read up on the problems and resolutions on those engines. In his tech tips section there is a wealth of knowledge on raw water pumps, turbo's, crankcase breathing, injectors, intercooler and over propping issues common with that Cummins series. If you get to the point where you are having the boat/engines surveyed remember that those engines are not sleeved and cannot be rebuilt in frame like some options can be.
Of course you can get a huge amount of information on the 38 or the 39 Bayliner over at the Baylinerownersclub forum as it has a very active bunch of current owners.

Hope this helps
 
IIRC, "The Other Gary" lives on a 3988 and it suits him well. I'm looking to step up and the only thing I don't like about the 3988 is the ladder to the bridge as opposed to steps on newer boats, BUT, I am rapidly approaching 60 and my knees have seen better days. Beyond that, a great boat.
 
Just in case everyone ignored it, the Mainship had issues with water backing up the exhaust. I'd research that carefully. I watched a vendor review a newly installed failed motor in disbelief. The owner's son said it happened when they came off plane.
 
After 20,000 miles of cruising the Atlantic ICW, the 3988 gets my vote as the biggest bang for the buck. The 3888 is there if you can't quite make the cost of the 39. The 40 foot Meridians which, more or less, replaced the similar sized Bayliners in the corporation's lineup is another step up in refinement and luxury.
 
"7.5% on each change of direction per my training instructor at the factory training school I attended.
Hmmmm When I went to school in the early 60s it was 3% per mesh. IMHO 15% loss is pretty far out. The advantages of the Vee Drive is in the ability to better utilize cabin space and most of all to get the engine noise out of the salon. Since we live in the cabin more then we are out riding around the Vee Drives have a place. I owned 10 boats over 30 feet. 7 were Vee Drive. Loved ever one of them except when changing out the packing. Having a Vee Drive would be my last reason for rejecting a boat. In all honesty I would probably turn down a straight drive because of less cabin room and noise.
 
boatbum
Thank you for the update... the boat has it's engines aft, the weight causes the stern to loose buoyancy when you pull back on the throttles, the deadrise combined with the placement of the engine put the motor low in the water, which makes ingestion more likely. However, it does make the cabin larger and keeps the noise down.
 
Two causes of water ingestion

Low exhaust elbows due to improper installation

Failure of water jacket on elbows allowing flow into engine. Again improper install or improper elbow design.

Both are much more common then they should be. Nothing wrong with the engines just the boat maker didn't know how to install them.
 
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