New Boat, and Propping

[Shannon Ritzert]

I recently purchased a new boat to me. Its a 31′ Bertram FBC. It has 2003 Yanmars 6LYA-STP 365 H.P. Each engine has right at 700 hrs on them. The gears are zf models 220A, ratio is 1.75:1 and she is propped at blade 22 x 24 x 1.75. I was told when lifted at the yard, that she weighs 18k pounds. It also refit by Cabrera Yachts in 2003. They tunneled the hull as well. This boat reminds me of Shooter that Seaboard refit.

The old owner told me that she takes a while to spin up and get on plane. I was told that its a Cabrera thing to build boats for speed. My first trip after having her delivered was as such. I left the marina, and opened her up to WOT to see what she has. Man, she is slow taking off. I didn’t record an accurate time or rpm, but I would say from 1200 to 1800 rpm took about 30 seconds. At about 1800 rpm, I pulled back on the throttles to about half throttle, then slowly opened the throttle as rpm increased. I would say it took me a good 2 1/2 to 3 minutes to get her to wide open. She does fly at WOT, but she’s a slug getting to WOT.

So, there’s a little puff of black smoke, more so out of the port engine than the starboard, but nothing like a diesel truck that someone turned the pump up on, and mosquito fogging everyone. I will try to attach a video if its not to large a file.

All things being fair and equal, There’s no boost or egt gauge. The exhaust out of the turbos are not done right. I don’t know when or if the aftercoolers were serviced, I do not see that in the service records. I am guessing she has 3-4 coats of bottom paint. She is a heavy fat girl, that I’d like to lighten up a bit. I say that because she hits 3,000 rpm at WOT. These are 3300 rpm engines.

I am guessing that she is over propped, does anyone have any suggestions on a good base size prop to start with, or should I be focusing more on engine issues and maintenance first?

Topic

[Shannon Ritzert]

Very Custom Bertram 31

was that the mcdougal boat?  They set all their vids to private 

[Shannon Ritzert]

Tony,

I have only pulled the exhaust side off because I wanted to see how bad it had been exposed to salt water.  I think the fortunate side of the whole thing os the low hours, and it seems to have been mainly used in the ICW. It was pulled and blocked almost every winter.  The water is not intruding sitting still, just rocking.  I’m guessing the water line is about a foot below the turbos.  <br /><br />

I’m planning on going out tomorrow and finish the egt/boost gauge install, and get some recordings off of that, then Im pulling the aftercoolers to bench, inspect, and clean those.  <br /><br />

What else are we looking for on the turbos?  Should I have a look on the intake side, or pull them down?

 

BTW, the youtube linc you posted says “for private viewing only”

[Tony Athens]

Very Custom Bertram 31

https://youtu.be/bK9oQ6iR5h0

 

[Tony Athens]

Looking at the exhaust, I am amazed the engines & turbos have not been more seriously damaged. 

Look up the article on the Shooter on this web site.. That is a “proper  exhaust” for this engine and this boat. That exhaust is still is user today but was adapted to QSB 480s when one of the Yanmar dropped a valve seat and proved not to be economical to rebuild.

Have you looked inside both turbos?

[Shannon Ritzert]

new pictures

here are the exhaust/ engine pictures.  

 

Does anyone have the thread size of the plug for the egt probe bushing.  I purchased the bushings from sbmar to do this install, but the threads really need cleaned up before installing the bushings.  None of my thread pitch gauges match up

Thanks!!

[Shannon Ritzert]

Thanks Tony

I am attaching the photos I have now, and I will get others attached when I get back to the boat.  I already know this exhaust system is not up to good standards.  One of my negotiation points on the boat was the lack of a good exhaust system.  I mentioned to the guy I bought it from that I am going to have to bring the exhaust up to snuff, and possibly replace the turbos.  HUGE HUGE difference between your photo and mine.  Mine are about 700 hours.  I would love these engine to see 12k hours!!

 

 

There is no rise on the exhaust, the mixer is attached straight to the turbo, and it is pointing down about 45 degrees. 

 

do you think I should plan to replace my turbos?  I will go ahead and start the search for those if need be

on the picture I sent, It looks like part of the fastener is missing, would you agree?

These engines at WOT photo tach at 3800 rpm in neutral at the dock, should I adjust them down in rpm?

 

These engines are in a 31 Bertram FBC prop pocketed set up kinda how yalls “shooter” project

 

I am having a trailer built, and I am attempting to get any data that is helpful before I pull it out of the water, and start making major repairs.  I will not be able to get the props in until around the first of the year.

[Tony Athens]

I said I know this engine well .  What that means in I put a set  of them in my bro’s boat and ran them for over 12000 hours.. It also had wet exhausts  This is a picture of his turbos at 12000 hrs after I pulled the engines and put them up for sale………………..As I said your turbos are eating salt water.

 

 

[Tony Athens]

Your turbos are eating saltwater—————–post good pics of your engines and exhaust

I know this engine well and it needs to SEE and accurate 3450-3500 RPM at WOT if you want to get the vessel up on plane easily and keep the engines/valves in ONE PIECE

 

Get your props off the boat to to a good prop shop for a proper scan,, Post the scan. & I’ll tell you what to do.

–

[Shannon Ritzert]

I got all the stuff in to install my egt and boost gauges. I am having an issue with the threads in the manifold that links the turbo to the exhaust manifold. I will get that sorted out soon, and get some data on egt and boost pressures.

I got some video on the exhaust side of the turbos, I am attempting to get those videos uploaded. I did get a still shot of the starboard turbo that I will attach too. I am curious about the star shaped fastener looks like about 1/3 of that is missing. (i don’t know the technical term for the fastener). Any thoughts on that?

Real live tach data Both tachometer gauges show to read about 100 rpm faster than a photo tach. These engines are supposed to high idle at 3300 rpm according to the data tag, but they actually high idle at 3800 rpm. Should I back the high idle adjustment to only allow these engines to tack at 3300?

I will get back with the rest of the data ASAP.
Thanks!

[donald roth]

You’re likely overpropped, but hunting in the dark without proper data.   You’ll need accurate rpm, egt, and boost pressure numbers.  <br />A peek at the exhaust side of the turbos would be my very first move.

 

 

 

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