2004 - 2009 Mainship 34T Model Year Differences

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PhantomF4

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Sep 26, 2021
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Hello, New boater and member here. I’ve been looking at the last generation of Mainship 34 Trawlers and was wondering if there were any significant differences or upgrades in the 2004 - 2009 model years? The only difference I’ve noticed from pictures is a 2-drawer refrigerator/freezer in a 2008 model as opposed to a single door unit in older years.

Also we looked at a 2006 34T and it was in great shape but it had 2200 hours on the single Yanmar 370 hp engine. Is that a lot of hours for a 15 year old boat or an area for concern? This would be our one and only boat going into retirement years.
 
When we sold our 2006 34T it was 13 years old and had 1600 hours on the main. Never any problem with the engine other than a periodic small leak at the front seal. Seems I needed to replace that every 800 hours or so. Mostly just a nuisance because I wanted things 'perfect'.

On any 34T make sure the vented loop on the generator has been run as high as it can be in the ER - some weren't and I believe that contributed to water backing into the generator on several boats.
 
Joining this thread b/c I am also interested in learning more about that generation of Mainships. I am confident, though, in saying that a well-maintained Yanmar with 2200 hours will serve its owner for many years to come. If you make an offer, make it contingent on a satisfactory engine survey - which is good practice in almost any case.
 
The Mainship 34T will become a classic over time. Decent build, great layout for a couple, wide beam all the way up to the flybridge. The only downside is it is a bit heavy and takes more power to push it due to its wide 14' beam on a 34' boat. I could cruise at 12 kts on mine with the single Yanmar at 2,800 rpm, barely up on plane (such as it is) but I usually ran it at 7.5 kts at 1,600 rpm.

Think in terms of the engine's age, not its hours. 2,200 hour is nothing. I didn't have a generator on mine, but your advice to check the exhaust is good. Look for a minimum of 12" rise over the water line. The main engine has an equalization line from the bottom of the lift muffler to near the water line which makes it impossible for sea water to back up into the engine.

After sixteen years, if it hasn't been done recently, service the raw water system completely and particularly disassemble, clean both air and raw water sides, reassemble with lots of grease and pressure test the after cooler. The Yanmar after cooler hasn't had as many problems as the Cummins, but this should be done every five years.

I sold mine about ten years ago for lots less than what they are selling for today. That tells the whole story about the market and the boat.

David
 
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The Mainship 34T will become a classic over time. Decent build, great layout for a couple, wide beam all the way up to the flybridge. The only downside is it is a bit heavy and takes more power to push it due to its wide 14' beam on a 34' boat. I could cruise at 12 kts on mine with the single Yanmar at 2,800 rpm, barely up on plane (such as it is) but I usually ran it at 7.5 kts at 1,600 rpm.

Think in terms of the engine's age, not its hours. 2,200 hour is nothing. I didn't have a generator on mine, but your advice to check the exhaust is good. Look for a minimum of 12" rise over the water line. The main engine has an equalization line from the bottom of the lift muffler to near the water line which makes it impossible for sea water to back up into the engine.

After sixteen years, if it hasn't been done recently, service the raw water system completely and particularly disassemble, clean both air and raw water sides, reassemble with lots of grease and pressure test the after cooler. The Yanmar after cooler hasn't had as many problems as the Cummins, but this should be done every five years.

I sold mine about ten years ago for lots less than what they are selling for today. That tells the whole story about the market and the boat.

David

David
Can you share your burn rate at both 12 and 7.5 knots/hour?
TIA
 
I can share some overall fuel usage figures.
'08 MS 34HT w single Yanmar 6LYA
I tracked fuel for a 1,000 SM cruise in 2019
Averaged 2.5 MPG with an estimated 75% of time at 1700-1800 RPM / 8.0-8.5 MPH and 25% 2700-2800 RPM / 13.0-13.5 MPH and excluding the estimated gen fuel usage.
Running between those 2 ranges is not practical / efficient.
 
David
Can you share your burn rate at both 12 and 7.5 knots/hour?
TIA

I look at the Yanmar prop power/fuel consumption curves for those figures. See attached. At 1,600 rpm (7 kts) it is burning 2-1/2-3 gph. At 2,800 rpm (12 kts) it is burning almost 13 gph. Those numbers track pretty closely to Bacchus' numbers. His boat is a little lighter as it has no flybridge so it will do a bit better.

I agree with Bacchus, those are the two speeds that make the most sense for that boat. Don't try to run it at 10-11 kts as you will be climbing the bow wave and that puts lots of stress on the engine.

David
 

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