i need help

[jamie mac]

I am a new owner of a 2006 mainship 30 rumrunner who is not to computer savvy. the boat has a 315 yanmar which original owner turned the rpms back from factory 3800 to 3000 rpms. i am trying to find out info on the 2006 mmodel or contact info for support. i know luhrs is bankrupt but is there any other forums out there i can access. or are any of your members that could point me in the right direction.

 

[JD]

Yahoo Groups. Mainship

mainship : This list is for Mainship Owners and others who want to own a Mainship.

What Yanmar do you have? 6LY???

How do you think he turned the RPMs back? What are the top RPMs the engine can do in neutral and what are the top RPMs the engine can do at full throttle under way?

 

[jamie mac]

Yahoo Groups. Mainship

mainship : This list is for Mainship Owners and others who want to own a Mainship.

What Yanmar do you have? 6LY???

How do you think he turned the RPMs back? What are the top RPMs the engine can do in neutral and what are the top RPMs the engine can do at full throttle under way?

I am the third owner guy i bought it from told me original owner turned it bsck because he was old school and didnt think a diesel should turn 3800 .it is a 6lpastp 315 it has the microcommander engine controls under load it is 3000 rpm in neutral i wont know til monday when i am home.it does have a five wing prop but i dont know if that is what it came with. thanks for the info.ps wot 21 knots

 

[JD]

I am the third owner guy i bought it from told me original owner turned it bsck because he was old school and didnt think a diesel should turn 3800 .it is a 6lpastp 315 it has the microcommander engine controls under load it is 3000 rpm in neutral i wont know til monday when i am home.it does have a five wing prop but i dont know if that is what it came with. thanks for the info.ps wot 21 knots

Well here is a start. I would go to Boat Diesel.com. Join as a level 2 member . That is $50 a year. Then go to the Engine section and then to Yanmar. Then to the older engine numbers an you will see your engine listed. The High Idle is 3,800 RPM. 80% of that is 3,050 which is where your engine should run most of the time. So what that means is that in neutral your engine should be able to rev up to 3,800 WOT and in gear it should be able to do the same at WOT. Now it may take it a minute or two to get there but it should obtain something real close to that in semi calm water. So is it doesn't get to 3,800 in neutral someone has tampered with the set screw on the fuel injection pump. This is not good. If it gets to 3,800 in neutral and not to 3,800 underway then the prop is not correct. This is not good either. If it does both then you can run at any RPMs you want but that engine needs to see 3,800 for a little time every time you leave the dock so to keep the engine clean and the turbo clean.

The folks on Boat Diesel will help you out. Tony Athens is one of the top Yanmar Technicians in the country and he can answer your questions as they come up. He has a very good article called 'Propellers Move Boats - Engines Only Turn Them" right on the front page of the home page.

I have the same throttle control system as you do and that I know of there is no way to dial it back.

The question is how did it get past the survey on the sea trial ?

 

[jamie mac]

thanks for the useful info. i was aware of the rpm issue when i bought the boat . i know the boat and owner who very rarely if ever had the boat over 15 knots . it was also professionly maintained and cared for . health reasons was his reason for selling. i got a good deal on it and i was researching the engine have decided to put it back to factory specs. the engine was inspected by a reputable diesel mechanic and has only 300 hours . so going forward i will be trying your test in neutral and under load to see if it is the engine or the prop. i tried to locate original owner but to no avail he also sold the boat due to health reasons. thank you JD for this and the yahoo link

 

[Karl-FL]

I had new twin Yanmars 315 hp installed some years ago in a boat I owned. Yanmar had a lot to say about what kind of props I was to use to get optimal performance, which were four-bladed props.

I would suggest getting the serial number of your engine and contacting Yanmar in the USA and see if they can trace the engine in their records and tell you what, if any, discussions were made on your engine. I cannot see the original owner doing anything on his own because that would violate the warranty. He had to make that adjustment in conjunction with Yanmar, if not at their factory before delivering the engines. I'm pretty sure the engines are made in Japan, but they do have a factory representation in the USA. In my case, living in Florida, I had to go through Mastry in Tampa, FL.

 

[DavidM]

The engine will only rev to 3,000 rpm in neutral? A 6lp is rated at 3,800 rpm at wot and a couple of hundred more in neutral..

That almost certainly means that the PO reduced the throttle throw so that the governor will only go to 3,000 rpm. Should be easy to readjust to full throw to reach full rpm.

David

 

[Fighterpilot]

Mastry ought to be able to help you with just a phone call, unless they aren't noted for their support regarding Yanmar.

 

[jamie mac]

thanks guys i am away working and will be home monday for two weeks and i will try neutral wot . found out today prop is factory correct . talked to my mechanic today and he said it would be no problem to reset throttle throw. glad you guys helped set me in right direction