Marinette 39 Sedan sea trial

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RBrown
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Re: Marinette 39 Sedan sea trial

Postby RBrown » Mon Apr 30, 2018 5:44 pm

It sounds like everything went well for you. You are correct about the engine RPM's being a little high. The should idle at 650-700 RPM's. That is where ours are set. Your WOT RPM's and top speed are in the ballpark as well. You loose some performance with the bridge enclosure.
If you still have the original points type distributors (ours were Mallorys), I would suggest that you consider replacing them with Delco EST's at some point. It was the best thing that I did to my engines.

Where are you transporting the boat from and what is the destination?

Best of luck with your new M.

Rob
1986 39' Marinette Double Cabin
Misty Blue
350 HP. Crusaders
Home Port: New Buffalo, MI.

bpboater
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Joined: Sun Jul 13, 2014 6:54 am
Location: Jamestown, KY

Re: Marinette 39 Sedan sea trial

Postby bpboater » Tue May 01, 2018 2:08 am

I found my tachometers on my 454 crusaders were not very accurate at low rpm. I use an optical tach to set idle speed - put a piece of reflective tape on the harmonic balance and use a laser tach to count the rpms. When engines are set to 750 rpm, the marinette tach shows 900.
1988 41 Marinette
Twin Crusader 454-350 hp closed cooling
Westerbeke 8.5 kw BTG
Lake Cumberland, KY

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shade2u2
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Joined: Mon Jul 21, 2014 3:11 pm
Location: Marietta, Ohio -mile marker 172

Re: Marinette 39 Sedan sea trial

Postby shade2u2 » Tue May 01, 2018 7:16 am

Thank you all for the help.

bpboater wrote:I found my tachometers on my 454 crusaders were not very accurate at low rpm. I use an optical tach to set idle speed - put a piece of reflective tape on the harmonic balance and use a laser tach to count the rpms. When engines are set to 750 rpm, the marinette tach shows 900.

Good to know about the 454 tachs. I have a Sun Engine tune up Kit that I could check the RPMs with - or am I going to get the same reading? I don't have a laser tach.
The Glendinning synchronizer was just installed last month. I wonder if it might need adjusted?

RBrown wrote:It sounds like everything went well for you. You are correct about the engine RPM's being a little high. The should idle at 650-700 RPM's. That is where ours are set. Your WOT RPM's and top speed are in the ballpark as well. You loose some performance with the bridge enclosure.
If you still have the original points type distributors (ours were Mallorys), I would suggest that you consider replacing them with Delco EST's at some point. It was the best thing that I did to my engines.
Where are you transporting the boat from and what is the destination?
Best of luck with your new M.
Rob

I am planning to take the boat on the water down to Catawba Island on Lake Erie. I will truck it from there to Marietta,OH to keep on the Ohio River. I hope to have schedule set up in the next day or so.

The seller installed new Pertronix FlameThrower electronic distributors and new hot coils installed last year. Here is a pic...
Attachments
distributor.jpg
John
1986 39 Sedan w/Crusader 454 & 1.92 drive.
1984 28 Express Hardtop FOR SALE
w/single 360 1.5:1 drive
Ohio and Muskingum Rivers (Marietta, OH)

bpboater
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Joined: Sun Jul 13, 2014 6:54 am
Location: Jamestown, KY

Re: Marinette 39 Sedan sea trial

Postby bpboater » Tue May 01, 2018 8:53 am

Glad to hear you have the new petronix coil and ignition module. I have those as well. If you find your idle does not always return to the same level, check the mechanical advance weights and springs in the distributor for rust. I had to clean the weights and springs for flawless performance. I am also going to buy new spring kits while they are still available -- just in case. As the springs rust, the diameter of the spring wire decreases and the spring tension does too.

Paul
1988 41 Marinette
Twin Crusader 454-350 hp closed cooling
Westerbeke 8.5 kw BTG
Lake Cumberland, KY

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shade2u2
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Joined: Mon Jul 21, 2014 3:11 pm
Location: Marietta, Ohio -mile marker 172

Re: Marinette 39 Sedan sea trial

Postby shade2u2 » Tue May 01, 2018 9:18 am

You'e description sounds like part of why the seller replaced the old distributors...

Thank you
John
1986 39 Sedan w/Crusader 454 & 1.92 drive.
1984 28 Express Hardtop FOR SALE
w/single 360 1.5:1 drive
Ohio and Muskingum Rivers (Marietta, OH)

javalin390
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Re: Marinette 39 Sedan sea trial

Postby javalin390 » Tue May 01, 2018 8:59 pm

Also note that some tachs have, depending on brand, have settings for 4, 6 and 8 cylinders, that may not have been set correctly when installed, and some have a tuning screw in the back that you can fine tune with a pocket screwdriver.
Jim Elias
1974 37' SedanFlybridge
Twin 360 Chryslers.
Marblehead, Ohio

Tsiguy
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Joined: Mon May 28, 2018 11:26 am

Re: Marinette 39 Sedan sea trial

Postby Tsiguy » Thu May 31, 2018 10:30 am

Hi all,
New to the forum, we are just about to visit our first Marinette this weekend, a 37 DC with chrysler engines and a 39.
w/crusaders. both look very clean, anything else outside the engines I should look for. (this would be a pre visit to determine if a survey will be orderred)
a quedtsion that I will search on the forum, range of these boats - average consumptions should be (2 gallons per engine)at low speeds ? 6-7 knots
thanks

jralbert
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Re: Marinette 39 Sedan sea trial

Postby jralbert » Thu May 31, 2018 9:54 pm

Tsiguy wrote:New to the forum, we are just about to visit our first Marinette this weekend...
Best of luck with your pending new purchase...here's hoping you can pick up some useful info here. Just an added thought on your post. Next time you wish to start a new subject -- this one had been devoted to a "sea trial" -- start a new thread rather than hopping onto an existing one. It keeps subject matter better organized. Nothing seriously wrong done here - no one's boat springs a leak - it's just a housekeeping protocol. Thanks for joining and hoping your chosen vessel sails on and on and on.
(by the way, with a 32 twin engine boat, I used to use around 1 gal per mile. I'm guessing 37/39 ft boats would use a little more depending on amount of fuel, water, gear, people carried. That's why the dockhands smile when you pull up for fuel)
-joel-
former owner 1988 '32 FB Sedan
Chesapeake Bay
twin 318 / 240 hp
Potomac MD

Tsiguy
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Joined: Mon May 28, 2018 11:26 am

Re: Marinette 39 Sedan sea trial

Postby Tsiguy » Fri Jun 22, 2018 11:30 am

thanks, just did it again, in another post. I will get better:)

Fastjeff
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Re: Marinette 39 Sedan sea trial

Postby Fastjeff » Sat Jun 23, 2018 7:11 am

35 mph at 4,000 rpm? Damn good performance!

My 'plastic boat' buddy doesn't get anywhere near that performance and his boat is a gas hog. Marinettes rule!

Jeff
"We live at the bottom of an ocean of air, not at the top." General Marvage Slatington