Transmission, Turbo, Tachometer, oh my...

[jruesr]

Seaslug,

My third pump (unknown specifications) is not in operation any more. The boat does not achieve the reported top end of the previous owner. My prop is now an 18 pitch vs the 20.5 that I started with. This story is very confusing. Could you post a picture of your old third pump and your new third pump and the part number of the new pump (from your reciept). I did not know that the pressure was adjustable???

Congratulations on your success.

John

[Seaslug44]

UPDATED PERFORMANCE FIGURES FROM MY 300HP Cummins...

In the ocean with 2' swells leftover from a storm. Both fuel tanks full. Water tank full. Completely loaded with gear (never got around to removing old stuff), ice, bait, tackle, etc... two of us on board, bottom not very clean (boat has been mostly sitting since April) and at 2,585 rpms as you can see from the attached photo of my new tachometer and my gps screen, the boat achieved 19 knots SPEED OVER GROUND on the gps which with those swells was easily equivalent to 20kts!

This is the end result of the new transmission, new turbo, new injectors, new water pump, new fuel prime pump, etc... New tachometer was perfectly calibrated and this rpm was confirmed using my new laser tachometer as well as the boat yard's. Now I just have to build a mounting plate for the tach since it is a smaller diameter than the old one.

Needless to say, I am extremely pleased with this performance considering the boat is a 1989 32' SF and from what I see and hear from others on this site these numbers are tough to obtain even for those who repowered to larger motors.

2010-07-23 06.54.05.jpg

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[ebbtide]

Tim and I were trying to get home quickly this past labor day and after we hauled our dink into the boat he powered the boat up and after several minutes there was a loud bang that sounded like an explosion and big black belching smoke erupted from the starboard side. We could no longer get the boat over 8 knots nor did we try as a high whining sound was coming from the engine. My sister had just had a seizure and was taken to Yale and the dam boat couldn't have failed at a more important time. Any ideas as to what happened? Its a Cummins turbo diesel /31TE. Feel like just pulling the boat and dealing with this come Spring. Any suggestions fellow owners?

[jleonard]

That sounds to me like one of the hoses or clamps on the compressed air intake let go.
I have had that happen on a truck. Bang when the hose slips off, black smoke because you have lots of fuel but no more air to burn it, and whining because the compressor side is now "open".

[jruesr]

Just to summarize my issues during this long discussion. The shaking problem that plagued me for so long was simply that my boat had no covers on the kiel opening. I made fiberglass covers and fastened them through the opening with threaded rods. No screws through the kiel. I had to put clamshell vents in to get more water flow into the opening but all the shaking problems disappeared completely. The design with two cutless bearings is very strong and works great if you just keep the covers on.

I have been using the boat now for 6 years and put about 5000 miles on her during that time and have no problems with the drive or shaking etc.

Thanks to all contributers.