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Quote:

Originally Posted by obrien (Post 2706871)

I assume you are not familar with the yanmar 440 he is running. The port for the exhaust temp is before the turbo, thats why i wanted to make sure he understood that. Most probes may be able to handle the temps, but I have seen these engines run over 1500 degrees and run that way for a while. I bet you the majority of diesel boats out there don't run pyros. especially now that most of them are controlled electronically, its not as easy to turn up the power. unless you have the program to do so. As of yet, yanmar won't let us touch anything on the new motors. The easiest way to know if your motor is overloaded is to check the WOT rpms. If you are not turning the recomended rpms then you need to cut back on your props or the load in the boat.

We ran the engines in the race boat at 1550 egts spinning up near 3600 rpms. However I would not recomend doing so since yours is a pleasure boat that you want to keep running reliably for a long time to come. I know the boat was sold to Greece a couple of years ago, and is still running well. I don't think the engines were ever turned back down.

It takes about 30 minutes to drill & tap the mixing elbow on a 6LY3-ETP so you can install a post turbo probe. :drink:

Quote:

Originally Posted by stirling (Post 2706534)

Jassman

Wat transmissions did you use single speed or 2 speed ?
And how did your boat accelerate out of the hole ?
and from 40-70 ?

single speed

lagged for a few seconds, turbo kicked in and got up on plane easily and accelerated good like a 525 boat

after 69-70 reaching the top end 74.6 took a while.

I remember Mastry Marine had designed an inner transom match for Yanmar diesel to a Bravo drive some years ago. In fact, there used to be a cat with this setup in Key West that would take 10-12 passengers on a tour around the island. Seems like it ran 60-ish?

Re-inventing the wheel?

Quote:

Originally Posted by Gordo (Post 2707096)

The Yanmar engine has an SAE industrial fly wheel set up. There has always been off the shelf parts to hook up SAE industrial flywheel set ups to Bravos. :drink:

Quote:

Originally Posted by 29Firefox (Post 2707337)

The Yanmar engine has an SAE industrial fly wheel set up. There has always been off the shelf parts to hook up SAE industrial flywheel set ups to Bravos. :drink:

On my other diesel boat ,a Sonic 28 with a Yanmar 6 LY ,I needed a bellhouse for a bravo to yanmar 6LY ,I called a lot of people in the US ,and did a lot of search ,but could not found a bellhouse ... I used a tailstock and a special made splined adapter to make the connection between enginea and drive,I was thinking about making one from a solid plate ali
If I only knew where to buy one back then...

Quote:

Originally Posted by Gordo (Post 2707096)

was it this one(this pic taken may this year)

Quote:

Originally Posted by 29Firefox (Post 2706908)

It takes about 30 minutes to drill & tap the mixing elbow on a 6LY3-ETP so you can install a post turbo probe. :drink:

Only problem is your exhaust temp is no longer accurate, it will be cooler that the reading you should get.

Quote:

Originally Posted by Gordo (Post 2707096)

The boat you are refering to is the Sea Rocket. there have been 15 or so built so far, and with the exception of the first two that were not built as sea rockets,we have been involved at Mastry with all of them. These boats all run 6LPs and bravo ones. The boats run in the 55-60 range.

To answer the question about the sterndrive package for yanmars, yes Mastry is the one who created that package. We had a casting made for a sterndrive bell housing that would allow the 6LP to mate with the bravo drives. We have also done a few boats with the 6LY engines and bravos, however those engines really have too much tq for the bravo drives. The only real success we had with the LY bravo combo was in a 36 Spectre cat with 2 speed transmissions and bravos. The boat ran just over 100 mph.

Quote:

Originally Posted by BOBCATMATHEWS (Post 2707409)

was it this one(this pic taken may this year)

That is one of the boats we did about 2 years ago, if I remember correctly.

stirling, I know we used to have a casting that would bolt the LY engines to a bravo inner transom plate.

29firefox is right there is a way to adapt the inboard version of the 6lp using a jack shaft setup, or we can covert them over to a sterndrive application.