MI Malahini Build, Post Flip.

Designs for inboard or outboard power

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vupilot
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Re: MI Malahini Build, Post Flip.

Post by vupilot » Tue Aug 06, 2019 7:48 pm

Congrats!!! Yes, let us know what problems you are having with the engine now. Been down that road as well on my 1975. Took a while to get it all worked out but got it running great eventually. First had a bad primer bulb brand new from the factory. The next year the fuel pump diaphragm. Then ran good for 2-3 years. Then chased a intermittent miss for 2 years that got a little worse each outing, turned out to be cracked coils on both cylinders. Somewhere in there I changed the switchbox and stator as well.

New outboards arent without issues either. My 1975 never left me stranded but my brand new 2016 Mercury did. The carb float is plastic and had just enough of a plastic burr from manufacturing to cause friction on the float hinge and hang up the float and kill the motor when coming off full throttle. Did it on 2 outings before I figured out what it was. But I will say, if you can swing a new motor its worth it.

As for the chop, you'll just have to slow down for the wakes.

footer
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Re: MI Malahini Build, Post Flip.

Post by footer » Wed Aug 07, 2019 4:14 am

Well, it appears I may have mixed the fuel a bit rich. I added some more straight gas to it and she started running right again. I also found my idle stop screw was stripped just enough to hold when I adjusted it, but slipped back after a bit.
I've owned several Harley's for the past 40 years, the first being a 1976 Harley Ironhead Sportster, that I rode for 27 years. So I'm used to working on the finicky mechanic's of old school engineering. But I got so spoiled by the newer fuel injected Harleys, that I don't ever want to own another frustrating money pit.
That being said, the old school Merc I have is by far my favorite LOOKING engine. My wife and granddaughter were complaining about how loud it is and it smells like gas, but I'm OK with that.
Thanks for the info. I thought I might tear into the Mag this winter.

JimmY
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Re: MI Malahini Build, Post Flip.

Post by JimmY » Wed Aug 07, 2019 9:21 am

Sounds like you may have figured out a few things with you motor, I hope you are able to enjoy the rest of the summer!
-Jim
Nothing says poor craftsmanship like wrinkles in your duct tape!

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Milhouse
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Re: MI Malahini Build, Post Flip.

Post by Milhouse » Sat Aug 10, 2019 10:48 am

Congrats on the launch! I too really like the old school motor on your boat.

Great job!
Jim
16' Ski Boat Restoration
17' Overnighter Sloop

I'd rather have a $h!tty meal than an $h!tty resume because a totally awesome resume will feed me steak one day - Steve Poltz

footer
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Re: MI Malahini Build, Post Flip.

Post by footer » Mon Aug 19, 2019 3:27 pm

Well, I have yo pull the plug on this old 1969, 65 hp, Merc. Nothing but problems running, or should I say, lack of. Its a beautiful engine and looks just plain cool, but I can never trust it to idle and accelerate. Its loud too. I actually had a list of 9 things that were mechanically wrong with it.
Fortunately, the guy will refund my money so I can put it towards a new engine.
So, I just ordered a new 60 hp 4 stroke EFI Mercury engine. It’s a little out of my tax bracket, but I’ll swing it.
I wasn’t sure whether I should go with the 60 or just a 40 would be fine?! We mostly just cruise around the lake, but the grand kids might come over to tube or whatever. I keep hearing, go big or go home.
I’ll report in sometime next week.
We did have an actual christening ceremony with about 30 friends and family. That was fun. I just tapped the steel nose with the bottle and popped the cork. I shared the bottle with my Mrs. and my Mistress. It was a good day. May the Lord bless this boat.
Attachments
42FB36C1-FF01-4579-8163-DB32A2D857F3.jpeg
The Christening of the “Mahogany Mistress”.
86CFE90B-0013-4EA8-80E7-81547C775839.jpeg
Moving along when it did run good.
D68AFC21-E515-4D89-B261-7FCD31E3F771.jpeg
Getting towed to the landing by Ryan.

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hoodman
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Re: MI Malahini Build, Post Flip.

Post by hoodman » Mon Aug 19, 2019 5:24 pm

I was sitting at the dock waiting for the Admiral and First Mate when an older gentleman came up and started asking about the boat. After a few minutes he said it looked like a really great old boat up forward but not so much in the back (referring to my brand new engine). "Why didn't I put an older engine on it," he says? So I bumped the key and engine starts instantly with no smoke. "That's why," I said.
Matt

Building a Geronimo......!
viewtopic.php?f=2&t=25139

Biss
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Re: MI Malahini Build, Post Flip.

Post by Biss » Mon Aug 19, 2019 5:38 pm

You will love the 4 stroke merc!

PeterG
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Re: MI Malahini Build, Post Flip.

Post by PeterG » Fri Aug 23, 2019 8:08 pm

Old Mercs can be temperamental and sometimes damn uncooperative. I have the Mercury manual and some of the tools and love tinkering with them as a hobby so I'll be good with one on my Malahini. But they're not for everyone. Great choice with the 60 4 stroke, you'll not regret the extra outlay for it.
Murphy's Law: Anything that can go wrong, will go wrong.
Griffin's Law: Murphy was an optimist.

footer
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Re: MI Malahini Build, Post Flip.

Post by footer » Fri Aug 30, 2019 4:39 am

PERFORMANCE UPDATE!
So, I pulled the old 65 Merc off my boat and installed a new 2020, 60hp, Standard Drive, Merc.

A little comparison: The old school Mercs have a similar gear ratio to the Command Thrust Merc, roughtly 2.3:1, where the new Standard Thrust gear ratio is 1.83:1. So, the Command Thrust, like the 60's Mercs, can swing a larger prop, like a 13"x17p give or take, where the Standard Thrust swings a smaller 10"x14p give or take.

So, I started off with a 15p 3 blade prop and was immediately disappointed. With four (larger) adults in the boat, it wouldn't get up on plane. It just plowed like a wake boat and the motor couldn't get up to it's power band.
So, I put a 14p 4 blade prop on it. Much happier. It doesn't get up on plane as fast as my old Merc did, but it did get up and get going and did it nicely with just my wife and I.

Another issue: the new engine is about 60 lbs heavier than the old one and with 4 adults in it, it porpoised when we got to about 25mph. The angle of the transom will not allow me to give any more negative trim without adding an angle plate. But, with just the two of us, it did fine. It runs about 30mph with that prop on it.
By the way, my 18 gal aluminum fuel tank is in the back between the motor well and back seat. My battery is also behind the back seat on my stbd side. So keep that in mind when building. I would guess throwing that weight up front will probably help with the planing and porpoising. I may try to install a outboard hydrofoil.

On a positive note, the new engine is quiet as a mouse, where you could barely hear each other with the old 65.
I would love to take a ride in Biss' Malahini with his Command Thrust 60 and compare the difference in performance.

There are a couple of very good videos about props and the importance of the right choice on youtube.

footer
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Re: MI Malahini Build, Post Flip.

Post by footer » Fri Aug 30, 2019 4:42 am

Pics
Attachments
IMG_7510[2].JPG
new 60
IMG_7516[1].JPG
new 60
IMG_7515[1].JPG
choppy day

Biss
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Re: MI Malahini Build, Post Flip.

Post by Biss » Fri Aug 30, 2019 6:14 am

Glad you got your new motor installed. Sorry that you are having some performance issues, sounds like they are all fixable. You may need to go down further to a 13p. What is your WOT rpm, I'm getting about 5900. Your manual should say what range you should be in. I think it is probably 5500-6000. You can plug your current performance numbers into a prop selector calculator and propbably get really close to the correct prop. I used Mercurys online prop selector to choose my prop.

I haven't experienced any porpoising, but I did shift a bunch of weight forward with the fuel tank. Sounds like you are close to getting it all tweaked. I'm sure you will really enjoy the convenience of the new 4 stroke when it is all setup! Looks awesome!

Sarnian
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Re: MI Malahini Build, Post Flip.

Post by Sarnian » Fri Aug 30, 2019 6:23 am

So cool - congratulations!....my guess is that knowing you have incredible reliability is a great relief.

I'm sure you will figure the trim out. For myself, I am resigned to porpoising, I will either describe it as a design feature or throw some trim tabs on there! :D

enjoy the weekend.

footer
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Re: MI Malahini Build, Post Flip.

Post by footer » Fri Aug 30, 2019 8:41 am

Biss, I have no Idea what my rpm's are as the guy that built my old motor told me I wouldn't need a Tach, so don't waste my money. Now I wished I wasted the money. I am going to put one in now.
What does WOT mean?
Sarnian, I've been researching those hydrofoils you bolt on your engine. May try something like that first, then trim tabs if no luck there. Gotta do more research.

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Bill Edmundson
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Re: MI Malahini Build, Post Flip.

Post by Bill Edmundson » Fri Aug 30, 2019 9:05 am

WOT means Wide Open Throttle.

Bill
Mini -Tug, KH Tahoe 19 & Bartender 24 - There can be no miracle recoveries without first screwing up.
Tahoe 19 Build

footer
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Re: MI Malahini Build, Post Flip.

Post by footer » Tue Sep 03, 2019 3:21 am

So my wife and 10 year old grand daughter made a video posted on YOUTUBE.COM called, "Tom's Mahogany Mistress" and my brother made one called, "The Mahogany Mistress" that I would encourage you all to watch.

https://youtu.be/qsxVv3ZlrKg

https://youtu.be/5YescmheEOA

Those of you from Glen-l will appreciate it as Glen-l is mentioned.

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