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Sea Trial expectations - vintage Connie

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evansjw44
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Re: Sea Trial expectations - vintage Connie

Post by evansjw44 » Fri Jun 24, 2016 11:22 am

Did you get a real GM 2-stroke engine tech? The GM 2-stroke engine has been out of production for several years; a victim of the EPA. There's lot of GM 2-strokers around and lots of parts but a diminishing pool of expert techs.

The throttle linkage actually controls the governor. which in turn controls the fuel rack that adjusts the fuel pulse of the injectors to reach speed set at the governor. The throttle does not control the injectors directly. The normal top governed RPM of a 6-71 is between 2300 and 2500 RPM no load. Now, there are variations of the GM governor The US Navy version has top governed speed set at 1900 with a "Flank Speed" of 2300. To get to "Flank Speed" there is a lever on the governor that must be moved to allow the governor to go to the full range. The early marinized 6-71s were done by Graymarine for the Navy. They sold cheap after the war and it is likely that is what you have, usually with non-navy governor. It is also possible the the governor has been replaced with a war surplus (cheap) governor. There is a nameplate on the governor which has the manufacturers name and model number on it. I would expect them to be the same.

I would expect you have Twin-Disc "mechanical" transmissions similar in some respect to the Paragon manual trans used on the CC 6 cylinder engines. You would also have a "Chris-o-matic" electro-hydraulic shifter mechanism. "Chris-O-Matics" are a bit peculiar in that they take a couple of seconds to complete a shift. Takes time to get used to that. You coould have Allison transmissions which are a whole different behavior.


Just as a benchmark, a "tune up" for a GM 2-stroke should probably run around $1000 - 2000 plus any injectors replaced at around $1000 each. Just my geusstimate. Again, you need to talk to a GM 2-Stroke engine expert. It is reasonable that one engine tops out at 2300 and the other at 1900. There is something wrong here.

One last tip. Make sure you have a 25 lb CO2 fire extinguisher handy in the engine room. CO2 can shut down a run away diesel. A diesel can run away (be uncontrollable) if it begins to suck in its own lub oil into the air intake. Shooting the CO2 in the air intake will kill it. GMs in particular are prone to runaways because the roots blower that pushes air into the cylinders is lubricated with engine oil. There is normally a flapper that can be release from the helm to close off the air supply should the engine begin to runaway. If you use it, it is manually reset at the engine. It can't be reset at the helm.

Good Luck Those GM 2-strokers are great engines.
Jim Evans

Jgoring
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Re: Sea Trial expectations - vintage Connie

Post by Jgoring » Thu Jul 07, 2016 12:16 am

OK.. final sale docs signed and money being gathered from all corners of the continent. So.. here's a pic or two. We'll see how she looks after 400 miles up the California coast late August..
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Jgoring
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Re: Sea Trial expectations - vintage Connie

Post by Jgoring » Thu Jul 07, 2016 12:25 am

Thanks Jim for your comments on the engines. The transmissions are Allisons, and seem to be in good shape. I'll make sure to have the big fire extinguisher available!

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tkhersom
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Re: Sea Trial expectations - vintage Connie

Post by tkhersom » Thu Jul 07, 2016 4:58 am

She is BEAUTIFUL! Congratulations. :D
Troy in ANE - Former President CCABC

1957 CC 21' Continental "Yorktown" (Mom's boat)
https://www.chris-craft.org/boats/22625/
1985 Formula 242LS "Gottago"
1991 Formula 36PC "Band Aids"

Life Is Too Short To Own An Ugly Boat

joanroy
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Re: Sea Trial expectations - vintage Connie

Post by joanroy » Thu Jul 07, 2016 5:50 am

I tell folks my cruiser is the best bad investment I ever made. Beautiful Yacht with a capital Y! Happy Boating!

jfrprops
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Re: Sea Trial expectations - vintage Connie

Post by jfrprops » Thu Jul 07, 2016 7:02 am

magnificent really!

John in Va.
1980 Fairchild Scout 30
19?? custom Argentine Runabout 16'
1954 Whirlwind deluxe dual ckpt 16'
1921 Old Town Charles River 17' (founding Captain, James River Batteau Festival)

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Captain Nemo
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Re: Sea Trial expectations - vintage Connie

Post by Captain Nemo » Thu Jul 07, 2016 4:24 pm

NICE!!! How could you not love it!!! 8)
Boats are to be made of wood, otherwise, God would have grown fiberglass trees.

Jgoring
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Re: Sea Trial expectations - vintage Connie

Post by Jgoring » Tue Aug 30, 2016 12:09 pm

Post Script - I was too slow closing, and another buyer appeared when we fell out of contract. He got a good boat for a good price. Lesson learned. Still in the hunt. It turns out, it is ALWAYS a buyers market for way too big way too old and way too wooden boats!

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Captain Nemo
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Re: Sea Trial expectations - vintage Connie

Post by Captain Nemo » Tue Aug 30, 2016 3:39 pm

:(
Boats are to be made of wood, otherwise, God would have grown fiberglass trees.

Jgoring
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Re: Sea Trial expectations - vintage Connie

Post by Jgoring » Fri Apr 14, 2017 5:26 pm

:D :D

Maybe final post script. Many months ago the 1955 Connie in Marina Del Rey slipped through my fingers. I learned a hell of a lot in the intervening year, and spent a hell of a lot on 3 additional haul outs, offers and surveys(I did the math - its was cheaper to do the 4 surveys this year than it would have been to own a boat, so.. in some ways I came out ahead?). Subsequent I chased several 57' connies, and they all hid some terrifying truths. One I had utterly fallen in lust with and would have closed on in spite of a 53 item survey - fortunately the insurance companies (yes, multiple) all refused to insure it on reading the same survey. They politely suggested... she was sinking. One in Minnesota was absolutely perfect.. and.. alas.. in Minnesota. Yes.. I priced the cost to move to the West Coast. Finally - a member on this forum posted his boat for sale in Portland, and it caught my eye. The engines - near perfect, and everything else near bristol, and the prior owners clearly suffered from serious OCDC. EDEN is now on my payroll, and I hope to be a good steward to her.
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robertpaul
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Re: Sea Trial expectations - vintage Connie

Post by robertpaul » Fri Apr 14, 2017 10:08 pm

Outstanding. I would love to see more photos of what looks like a really sweet (albeit YUGE) yacht.
1937 35' Double Stateroom Enclosed Cruiser

Jgoring
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Re: Sea Trial expectations - vintage Connie

Post by Jgoring » Tue Apr 18, 2017 12:50 pm

robertpaul wrote:Outstanding. I would love to see more photos of what looks like a really sweet (albeit YUGE) yacht.
ehh... maybe I just have small hands! ;-)

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