Possible Re-power 07 Marlin

[Angler Management]

Thanks for your input everyone.

It amazes me how strong peoples opinions are in some areas. I can't tell you how many mechanics I've talked with who say "X" is "garbage", while the next guy says "Y" is "a piece of crap" and the next guy says "I wouldn't put Z on the boat of my worst enemy".

The best advice I found was from the local Grady dealer, which was "They all work well if you maintain them and they all break somehow in the salt environment."

I've decided to "punt" this decision into the fall by purchasing some used Yamaha 250's with the same number of hours to keep my summer fishing plans alive, and then re-evaluate the entire subject again in the fall. Best to make big decisions without pressure, and these 250's should be a quick job and get me back in business ASAP.

Thanks!

 

[wahoo33417]

Well, to add another observation. If you stayed with Yamaha's newer F250, I believe you’d still notice improvement in power and fuel economy.

When I repowered from a 2005 Yamaha 3.4L F250 to a 2010 4.3L F300 on the same boat, I noticed a significant difference in midrange torque and my fuel economy got a bit better.

I'm not so sure this difference is as attributable to the 50hp as it is to the greater displacement and the variable camshaft timing of the 4.3L. I suspect I rarely use those 50 hp.

So why should I pay $1,500 more for “programming” I’ll rarely use, I asked when I bought the engine? For resale of course, was the answer.

For me, this power is most noticeable when getting on plane obviously, but also when I’m trying to stay on the back of a wave coming in a nasty inlet.

Rob

 

[Doc Stressor]

If you are going to be using one of your main motors for trolling, I would stay away from Yamaha. Their bigger 4 strokes have reputation for making oil when trolling or operating at less than 4200 rpm under load.

My 3.3 liter F250 has the problem and I cannot troll at all, even at the higher speeds typical for southern species. If I troll for even 4 hr, the oil level comes up several inches over the full line. I typically need to remove oil between 100 hr changes. I once let it go too long and oil went through the crankcase breather into the intake manifold and fouled up the spark plugs.

This has been an issue for Yamaha for a long time. If you Google "Yamaha making oil", you'll see that the newer 4.2 liter 250 and 300 hp engines often have the problem. Some folks have had luck running the engines very hard during break-in and/or using low pitch props to reduce the engine load. My suspicion is that the problem is related to the absence of an O2 sensor. Without an O2 sensor, the ECU really doesn't know how rich the engine is running. It has to depend on a pre-programmed fueling profile that does not sense the actual load on the engine. So unless the rings are seated very well, blow by containing unburned fuel gets into the crankcase under conditions where the engine is running rich.

Making oil has been reported in other brands of 4 stroke outboards, but it seems to be much more common in Yamahas.

 

[UCPA111]

I repowered my Seafarer with a Verado inline 6 supercharged 300. One of the last of that motor (installed May of this year).
I looked at all the motors. Can't really say anything bad about any of them.
I was down to Honda (250), Yamaha (250 or 300) or Mercury (250 or 300).
I liked the idea of buying an American made product.
I love the vessel view control and monitor system, with trolling mode control (10 rpm increments), cruise control, etc.
DTS binnacle is super smooth. Dock mode is nice feature.

Motor performance is outstanding. Hard top, full fuel, 5 people, ice/gear. 48 mph top speed before I raised the motor 2 inches.
31 mph cruise at 2.6 mpg.

I can tell you that the inline 6 is so dang quiet...and so silky smooth. Everyone who has experienced it is impressed. Not that Yamaha or others are bad...it's just how refined this motor is.
Going 31mph....punch it...and you better be holding on or you're out of the boat. Yamaha is Cadillac....Verado seems like a Ferrari.
I have 55 hrs on it. Run out 5-7 miles...troll for several hrs at 550-590 rpm....run back. No oil problems. Not making oil. Oil looks great.

I am not sure you can really go wrong....but just sharing my experience. My motor is mounted on a bracket. If you want some videos, let me know.