There are some great threads from a few years ago regarding low rpm. Heres a list of all the things I can remember that were checked when I was investigating: Growth on hull or prop, autoprop that needs refurbishing...Fuel tank valve, lines, 2 filters, pump (some engines have a lift pump and hi press pump), injectors...air intake clogged, bad turbo, clogged exhaust (especially the elbow), bad cylinder/piston, timing wrong...what have I left out?
We're you able to get 2800+ rpm in the past?

I'd start with prop, fuel filters and Turbo/exhaust elbow. You are the first one I remember with low rpm and 100 HP Yanmar. I'll be interested to hear what you find.
Kent
SM 243 Kristy
Brunswick GA USA

Sent from my iPhone

On Aug 28, 2013, at 8:19 AM, "alan_leslie_elyes_sm2k" <divanz620@...> wrote:

we too have the same issue with Yanmar 100hp

It will go to 1900/2000 rpm no problem and in slight seas maybe 2200, but no more...

It is possible that the autoprop is dirty ..hasn't been cleaned for 4 months...and we also have the issue of black smoke (don't see it) that fouls the hull, and is a devil to get off.

We motored 50+ hours on our last passage and the black stain is still there despite lots of cleaning....

In my experience...black smoke = fouled injectors, dirty air filter....or over pitched prop....I 'm sure I don't have the first two...but I don't understand how an autoprop can be over pitched..????

mystified...

Alan

--- In amelyachtowners@..., Richard03801 <richard03801@> wrote:

Hi all, Miles, is correct and yes 2800 is what we get at full that is Amels settings. Should you be Having problems getting there they can be many fold. Most of them come from well minded persons who do or may not understand our yachts.
A good service person will collect facts first then sort out issues.
Running the boat at the dock is not a suggested means of testing the engine/prop. You need to have the boat underway.
On "older" boats ck for air and pressure leaks in the fuel system especially if you've have done work on the injection system. Air leaks can and do occur before you get fuel leaks. Keep it simple first.
Good luck to ALL

Regards
Capt Richard Piller
Fairbanks Yacht Group llc
Full brokerage and service for all yachts
Cell 603 767 5330

On Aug 27, 2013, at 13:53, Alexandre Uster von Baar <uster@> wrote:


Good afternoon MIle,

I agree this is hard to believe the Super Maramu could not exceed 2200 rpm out of the factory...

Were you ever able to reach 2800 rpm?

Last november had antifooling done and prop clean, tied at the dock the engine would reach 2500 rpm, but only 2200 rpm at sea...
2 weeks ago, I cleaned the turbo, prop was cleaned (not the hull) same thing: 2500 rpm tied to the dock and only 2200 rpm at sea...

Seems to be the same for so many people...
What do we do wrong?

Alexandre

--------------------------------------------
On Tue, 8/27/13, Miles Bidwell <mbidwell@> wrote:

Subject: [Amel] Re: Volvo Penta TMD22 Low RPM
To: amelyachtowners@...
Date: Tuesday, August 27, 2013, 12:37 PM


























Hello all,



I think that you will find that the boat is not "over
propped as it came

from Amel. Someone who says it is does not understand the
boat.



I bought my Super Maramu new in 1998 and Amel explained that
the engine and

prop were set to give the boat a maximum RPM of 2800 and
push the boat at

hull speed which is about 8 knots depending on sea
conditions. The idea of

governing the engine to less than its maximum rpms is to
move down the

torque curve and take advantage of the auto-prop self
adjusting ability and

increase mileage and reduce noise. I am now having
mysterious problems with

the engine which may be related to the high pressure fuel
pump. If the

motor is running as it should (a big if), and the prop is
clean with smooth

bearings, it should run up to 2800 if the boat bottom is
very clean.

Beware of shops that tell you otherwise and then charge you
for unnecessary

work.



Miles (sm 216 Ladybug, Newport, RI)
































[Non-text portions of this message have been removed]

[Non-text portions of this message have been removed]