Hello from a newbie

[Chesapeaker82]

Hello all I am currently looking at buying Mainship 34. It is being advertised as a 1977 but from the pictures it appears to be a mkii wich would put the boat in the mid 80s. My main concern is it has been repowered with a cat 3208 325hp. From my research this seems like alot of hp for the Hull. I would love to hear people's opinions on this motor in this boat! Can I still achieve good fuel mileage? Will it mess the motor up by not loading it? The motor has 295hrs so it brand new but was installed 10+ years ago. The boat has also been on the water for 3 years. It had a new shaft and prop installed. Could these be potentially damaged by the long duration in the water? Ahhhhhh so many questions! Anyway happy to be here thanks in advance for any input!

[RT Firefly]

Greetings,
Welcome aboard.

[Chesapeaker82]

Here are a couple pics from the ad.

[Pete Meisinger]

wow! what a clean install.

I don't know a lot about "Cats" other than they are good engines.

That Mainship is a plaining hull, it will get on top of the water, not strictly a trawler. That looks to be a good engine/boat match. Run it slow for good economy and kick it in the butt once in a while to clear it out.

You may be slightly overpowered but it's nice to be able to cruise at 25+ mph once in a while.

Go for it,

pete

[Comodave]

Welcome aboard. The 3208 is a good engine particularly since it isn’t a turbo version. Should be good for many thousands of hours. There are some that have big block gas engines in them so a 210 hp diesel should be fine. Looks like a nice boat. How are the decks? Any wet core? If not I would jump on it in a heartbeat. Good luck.

[Chesapeaker82]

Decks up front and fly bridge have been restored. Cockpit has not and it needs new fuel tanks. From what I've seen online it sounds pretty standard for these boats.

[GregBrannon]

Welcome! Good luck with finding and acquiring the right boat!

[Comodave]

Originally Posted by Chesapeaker82

Decks up front and fly bridge have been restored. Cockpit has not and it needs new fuel tanks. From what I've seen online it sounds pretty standard for these boats.

Cockpit and tanks in that boat should be fairly straight forward to fix. Hope it works out for you.

[johnma]

Its definitely not a MK I, its a MK II. You should ask your questions on the Marlow Mainship section of the forum . Not sure how that boat will run on plane there are a lot of 34 I II & III owners on here but they're looking at the other sections of the forum, not the welcome mat.
Welcome btw
John

[Chesapeaker82]

Originally Posted by johnma

Its definitely not a MK I, its a MK II. You should ask your questions on the Marlow Mainship section of the forum . Not sure how that boat will run on plane there are a lot of 34 I II & III owners on here but they're looking at the other sections of the forum, not the welcome mat.
Welcome btw
John

Thanks! I'll ask on that section!

[Olebird]

Welcome aboard. The Cat 3208 series were originally "throw aways" not designed to be rebuilt, although many have been. My 2003 Mainship Pilot II has 315 hp stock from Mainship -that engine should be fine for that hull. Check the fuel tanks carefully, fuel spills/leaks can get expensive. Make sure you can buy "eco" insurance coverage for it. Last two digits of the Hull number will tell you the year of mfg.

[BruceK]

OP says it`s a 325hp version. Looks turbo to this non mechanic. Neat looking boat which could really suit a keen fisher.

[Mischief Managed]

Originally Posted by Comodave

Welcome aboard. The 3208 is a good engine particularly since it isn’t a turbo version. Should be good for many thousands of hours. There are some that have big block gas engines in them so a 210 hp diesel should be fine. Looks like a nice boat. How are the decks? Any wet core? If not I would jump on it in a heartbeat. Good luck.

That big turbo-shaped thing is a turbo. Regardless, 3208s are reliable and long-lived up to 375HP, so that one will last a long time.

[Mischief Managed]

Originally Posted by Olebird

Welcome aboard. The Cat 3208 series were originally "throw aways" not designed to be rebuilt, although many have been. My 2003 Mainship Pilot II has 315 hp stock from Mainship -that engine should be fine for that hull. Check the fuel tanks carefully, fuel spills/leaks can get expensive. Make sure you can buy "eco" insurance coverage for it. Last two digits of the Hull number will tell you the year of mfg.

I have 3208s and did a ton of research before buying a boat with them. 3208s were always designed to be rebuilt twice, they just need to be bored out .020" over, then bored .040" over. This means they can't typically be rebuilt in the boat like a Detroit, but it would be crazy to throw one away if it needs a rebuild; they have very heavy-duty parts on them that can last forever.

[Fletcher500]

3208’s are also used fairly extensively shore side for fire pumps in large buildings. Lots of them out there still going strong and they don’t get treated very well in those applications.

[Swa]

Welcome and nice find. Yes thats a nice looking set up. 325 hp 3208 would be my choice for re-powering. The engine and boat are bullet proof. Would like to see more pics Good luck

[firehoser75]

Hello and Welcome "Newbie".
Yes you can run that engine at about 1/2 throttle with no real problems. As previously advised, run her up to Cruising RPM or WOT once in a while to "blow her out" and it will last a long time. Tony Athens, a very respected diesel guy says he has never seen an engine damaged by running it too easy (not talking here no load idling which is bad).
My boat is only a bit larger than that, and I have a Cummins 330 hp and we run all the time at 1/2 throttle doing about 7-8 knots. It is nice to have the ability to open up for some more speed should the need arise, and often in larger following seas we do increase our speed to "smooth out" the ride.
Good luck

[Baloo]

Welcome aboard! I recently purchased a 1979 Mainship ii. Mine still has the stock Perkins in it. Looks like a nice boat, and man is that engine room clean! They are nice boats, I am happy I bought one.