Re: Cruise and Max RPM #solution


Thank you Marco.  I still have the old Hurth transmission that was on the old Volvo.  I'll have to check its gearbox ratio.

SM 243

On Jul 5, 2020 5:40 PM, Marco Mancini <marcomancini61@...> wrote:
Kent, we are using the same h6 was setted up by amel for the previuos TMD22 without modification. I discussed for a while with the Autoprop dealer for the defintion of the 2,3 gearbox ratio  becouse I thought in the beginning to use the same gearbox ratio of the other yanmar 100 cv installed on the SM . But this new version ( 110cv) run at maximum only at 3200 rpm instead of the 3800 rpm so we needed a smaller ratio.  The engine at its maxum reach all the 3200 rpm . Indeed the boat runs to above 9,2 Knots but she goes above her  critical velocity that with the usual formula is  8,7  knots . From what my brother is describing to me  ( I leave in Milan ) there are not vibration and the engine is very silent . 

Il giorno 05 lug 2020, alle ore 20:09, karkauai via <karkauai@...> ha scritto:

Hi Marco,
Are you still using the AutoProp H6 with the new engine?  If yes, did you have it modified in any way?

SM 243

On Jul 5, 2020 1:18 PM, Marco Mancini <marcomancini61@...> wrote:

the TMD22 with the mechanical gearbox (2,8 reduction factor) and the autoprop h6 was probably  never reached in our 20 years of SM  more than 2500 2600 rpm ,
The TMD22 engine characteristic curve show that the 78 hp ( the max power) is obtained at 3500 - 4200 rpm  but at 2500 the curve show 40 hp and the boat has never reached more than 7.5 knots 
Now we have moved to the yanmar 110 cv,  the new version of the yanmar 100) with gearbox with 2.3 rduction factor   (midway betwenn the 1.97 of amel 54 with 110 volvo and  2.8 of the yanmar 100 )  that is  the new version  of the well known  Yanmar 100 cv  installed by Amel  after the TMD22. In Italy due to a severe restrictions of  omologation certificate we had also to afford the cost of new homologation certificate but we hare happy with this change . indeed the boat seems to go much better, it has a cruise speed of 8,5  at 2300 rpm over 3200rpm ( max engine regime)  and also in the manoeuvres she is more prompt than before . 
cheers and good wind . 
marco mancini 
SM 304 

Il giorno 25 giu 2020, alle ore 16:55, Thomas Peacock <peacock8491@...> ha scritto:

This is question without a definitive answer. 
We also have the TMD22. When we bought our boat (about 4 years used), we could get almost 3,000 rpm at max throttle. Our local diesel guy suggested cruising at 80% of max, or 2,400. Our max started to lessen within about a year. 
Ever since then, we have usually not been able to max out at 3,000. Usually max is 2,400 to 2,600, so we cruise at 80% of that.
Issues affecting max cruise rpm include bottom, prop (even one barnacle can make a difference), turbo condition, and countless others. 
I suppose that, just like me, the Volvo has also lost a little mojo as it has aged. 

Tom Peacock
SM 240 Aletes
Chesapeake Bay

with its tiny keyboard

On Jun 25, 2020, at 10:10 AM, JOSE PRIETO <prietomd11@...> wrote:

Hello Amelians!  I am in the process of learning my boat.  The engine is a Volvo TMD22, with autoprop h6 propeller.
I found some threads here on the forum related to this topic, but none conclusive about what is the ideal cruise rpm regime, and what is the maximum rpm?  I can't get more than 2100 rpm!
 Any suggestion?

Jose Prieto
SV Wayag, SM 323
Currently Alicante, Spain

Join to automatically receive all group messages.