Nag Juice Posted February 1, 2017 Report Share Posted February 1, 2017 Maybe this is for Skip, but while discussing with other forum members I figured I'd post. Since older MAs are still in the population, they were constructed for 2 strokes. What did MBC do to compensate for the additional weight of 4 strokes? Was the transom reinforced? I know the TM Batteries were moved forward, but I saw a picture of an older MA yesterday with a newer heavier 4 stroke. The transom was cracked. Before the tree killed my first one, I was going to repower but being it was built well before 4 strokes, I'm curious if it would've held the additional weight or how much it would've squatted. The pictures are the same hull, just 75lbs difference in outboards. One is a 1997 the other is 2006. Link to comment Share on other sites More sharing options...
hurricane Posted February 1, 2017 Report Share Posted February 1, 2017 When you say older MA's, are you thinking pre 2000 models? I think the 2000 an newer models might have had 4 stroke weight in mind when they were built. I have the build sheet for my boat and an F150 was an option in 2003. Link to comment Share on other sites More sharing options...
Nag Juice Posted February 1, 2017 Author Report Share Posted February 1, 2017 Right. I'm just wondering when MBC started to realize weight might be an issue and took corrective actions Link to comment Share on other sites More sharing options...
hurricane Posted February 1, 2017 Report Share Posted February 1, 2017 Ya, it a good question. Link to comment Share on other sites More sharing options...
triplec Posted February 2, 2017 Report Share Posted February 2, 2017 Yeeowza 160 pounds is big diff! Wondered my self as well when the time comes to repower. My 96 150 2 stroke Yamaha manual says it weighs 440 and new F150 weighs in at 480 it looks like . Thats another 40 pounds in the worst place for weight distribution for sure but not 160 pounds either. Someone suggested tossing a bag of sand back there to get an idea. few pounds to the good if the oil tank goes away too I reckon. Interesting question Nag... Link to comment Share on other sites More sharing options...
Nag Juice Posted February 2, 2017 Author Report Share Posted February 2, 2017 Sorry, you're right. 410 pounds was my last Motor. I must've misread the weights before. Either way, I'm curious if there was any structural differences to compensate for the added weight. I shop for boats all the time and when I pitch MAs to people, the older engines come up with the weight differences etc. I'd like to be able to give/know concrete information about hull changes/modifications. Link to comment Share on other sites More sharing options...
wthree3 Posted February 2, 2017 Report Share Posted February 2, 2017 My 05 18.5 has C/K in the area of the spashwell. Don't know if that was done on all or just a few. Mine is also VARIS construction so it may be unique. I would think that the weight difference in engines is minor compared to the thrust and torque loads on the transom from the engine. The immediate throttle response of a 2 stroke may impart more load than the more gradual power of a four stroke. The absolute worse load on a transom has to be when your lower unit hits bottom and you come to a sudden stop. That probably accounts for more stress cracks in transoms than anything else. Link to comment Share on other sites More sharing options...
fsusteve Posted February 2, 2017 Report Share Posted February 2, 2017 And jack plates, adding a four stroke any different than a two stroke on a j/p? Link to comment Share on other sites More sharing options...
whichwaysup Posted February 2, 2017 Report Share Posted February 2, 2017 1 hour ago, wthree3 said: My 05 18.5 has C/K in the area of the spashwell. Don't know if that was done on all or just a few. Mine is also VARIS construction so it may be unique. I would think that the weight difference in engines is minor compared to the thrust and torque loads on the transom from the engine. The immediate throttle response of a 2 stroke may impart more load than the more gradual power of a four stroke. The absolute worse load on a transom has to be when your lower unit hits bottom and you come to a sudden stop. That probably accounts for more stress cracks in transoms than anything else. Correct me if I'm wrong, but is this really accurate? I was under the impression that outboards are not held in their running position mechanically, they pivot freely and are kept down by weight/force. When you run aground, the engine pivots up, minimizing the stress on the transom. If that's not accurate, let me know. BTW, Wthree3, sure would love to see pics of that 05 MA. Just to drool a little. On this topic overall, Nag and I have been arguing how much the weight actually matters (unless there is a jack plate involved), since the weight of an engine is applying downward force (vs. torque/twist) on the transom. I would have to think that even 160 lbs of static force on the transom would be of minimal impact vs. going from a 115 to a 150 HP engine, where the force is actually putting a non-linear force on the transom. A jack plate would obviously change the dynamics a bit, by putting the engine weight off the back of the transom and as a result increasing the impact of the force applied by the prop. All of these (brilliant) comments above are coming from an uneducated source and by the same brain that still thinks that electricity is completely incomprehensible, so feel free to educate me if you have facts and expertise! Link to comment Share on other sites More sharing options...
mulligan Posted February 2, 2017 Report Share Posted February 2, 2017 I am not an engineer but would guess you are going to put more stress on the transom by bouncing down the road at 60mph than you would running the boat no matter what the motor weights. Link to comment Share on other sites More sharing options...
wthree3 Posted February 2, 2017 Report Share Posted February 2, 2017 Smaller outboards are free to rotate up when in forward. Except they usually have a tilt lock that engages in reverse, otherwise the motor pops up when you gun it in reverse. Large outboards are locked in position all the time via the hydraulic tilt cylinder. Link to comment Share on other sites More sharing options...
wthree3 Posted February 2, 2017 Report Share Posted February 2, 2017 Here you go Whichwaysup.. Link to comment Share on other sites More sharing options...
whichwaysup Posted February 2, 2017 Report Share Posted February 2, 2017 Can you make sure I'm the first to know when you decide to sell that thing??? WOWSA!!! Link to comment Share on other sites More sharing options...
wthree3 Posted February 2, 2017 Report Share Posted February 2, 2017 Will do, but you may have a long wait. I can't think of another hull that I'd rather have that would be as versatile as this one. Link to comment Share on other sites More sharing options...
whichwaysup Posted February 2, 2017 Report Share Posted February 2, 2017 Based on my 1987 MA, I happen to know that these hulls last long past the 30 year mark. I'm patient. Link to comment Share on other sites More sharing options...
hurricane Posted February 2, 2017 Report Share Posted February 2, 2017 3 hours ago, wthree3 said: Smaller outboards are free to rotate up when in forward. Except they usually have a tilt lock that engages in reverse, otherwise the motor pops up when you gun it in reverse. Large outboards are locked in position all the time via the hydraulic tilt cylinder. The trim unit has a valve that releases pressure and allows the motor to tilt when an object is hit. I'm sure there is some stress, but it's not a direct solid immovable impact. I think after 04 maybe 05 all MA's were carbon fiber, I think that's kinda what killed them. The cost went up sales went down bay boats took over and the Redfisher was cheaper. Link to comment Share on other sites More sharing options...
Nag Juice Posted February 2, 2017 Author Report Share Posted February 2, 2017 I know my hatch lids are Carbon Fiber but not sure about the hull. I kind of doubt it with the way it rides. Link to comment Share on other sites More sharing options...
fsusteve Posted February 2, 2017 Report Share Posted February 2, 2017 Hatches are, don't believe hulls were until near the end of the production run Link to comment Share on other sites More sharing options...
hurricane Posted February 2, 2017 Report Share Posted February 2, 2017 From what I've seen the whole cap is carbon fiber. I don't think the hull is carbon either, but I don't know that for sure. Nag look in the bilge at the underside of the splashwell. Then wait till you try to drill it or cut it............ Link to comment Share on other sites More sharing options...
hurricane Posted February 3, 2017 Report Share Posted February 3, 2017 7 hours ago, wthree3 said: Here you go Whichwaysup.. Thats a fine lookin' boat! Link to comment Share on other sites More sharing options...
algi Posted February 4, 2017 Report Share Posted February 4, 2017 Hurricane are you out of tarpon springs and launch out of anclote?? Link to comment Share on other sites More sharing options...
algi Posted February 5, 2017 Report Share Posted February 5, 2017 2004 17MA 115 yamaha 2stroke Link to comment Share on other sites More sharing options...
hurricane Posted February 20, 2017 Report Share Posted February 20, 2017 On 2/4/2017 at 6:55 PM, algi said: Hurricane are you out of tarpon springs and launch out of anclote?? Sorry i just saw this. No I mostly fish outta Gandy or on the South Shore. Link to comment Share on other sites More sharing options...
fishmanjj Posted February 20, 2017 Report Share Posted February 20, 2017 On 2/2/2017 at 1:47 PM, wthree3 said: Here you go Whichwaysup.. VERY NICE LOOKING........... Link to comment Share on other sites More sharing options...
mminassian Posted February 22, 2017 Report Share Posted February 22, 2017 On 2/20/2017 at 1:14 PM, hurricane said: Sorry i just saw this. No I mostly fish outta Gandy or on the South Shore. I launch from the Harborage in St Pete, we should meet up sometime! Link to comment Share on other sites More sharing options...
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