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TAMD41Abs high RPM low speed

rcolano

New member
"Hello
I have another Quandry


"Hello
I have another Quandry about my 41 ft. cabin cruiser with these engines. First i have to say i was disapointed to find out that these huge turbo engines only produce 160 hp. each. I bought this boat at an auction with little time to inspect and the bid sheet stated"370 HP. Volvo diesels" What they meant to say was if you andd the two engines and the generatos hp. you might be able to find 370 hp lol. Anyway my problem is that the engines will scream at 3200 rpm but i cannot get over 11 knots. I would like to know at what rpm the engines deliver peak torque. The props are a 19 pitch ant he diameter (here's the weird part) is 22' on the stbd engine and 23 on the port. ???. I have consulted a local prop rebuilder and he has recomended that we bring the larger prop down is sixe to match the smaller one and increase the pitch by 2. This should equalize and increase the load on the engines and reducing the max rpms that they will attain and bring uit down where it produces more torque. I am not certain but i believe max. torque is at about 2300-2400 rpm, anyone got the specs on this, the shhet i have has such fine print i cannot make it out and the repair manual says it is different 4 variously equipped models. Any help on this topic will be of great help.
Thanks Rich colano"
 
"Theese engine should be able

"Theese engine should be able to obtain minimum 3600 rpm to 3800 rpm at full throtle. Forcing the max rpm down as You suggest is a quick way to kill them. I do not know what kind of props You are running, but hopefully 4 blades. Is Your speed reading from log or GPS?"
 
"Thanks for your response
sms


"Thanks for your response
sms like alot of rpms for a diesel?. yes 4 blade props. Speed reading fom digital gauge coupled with depth finder and GPS. any idea what rpm engines produce peak torque, if that was known i could repitch to let them obtain a few 100 rpm's above that. Prop shop wanted to know gear reduction ration, i looked and it is 2.26 to1 seems like alot of reduction, but maybe that explains engines high rpm,
Thanks Rich"
 
"In Your 'case' I woul

"In Your 'case' I would aim for 3800 rpm at full throtle. You may safely cruise at 3200-3400 providing You have the 'leisure' version and not the 'light commersial duty' engines which in fact Your HP indication says. Normally those engines were rated 180-200 (without gear). You have the max torque around 2600, depending a little of Your pump setting. You should feel it rather well when the turbos kicks in!"
 
"Kevin thank you for yor advic

"Kevin thank you for yor advice. Would you mind speaking with me on the phone, you seem very knowlegable on these engine and a short conversatin could save me weeks of messaging to you. i am scheduled to drive down this coming weekend to spend a few days working on my boat and plan to spend some time on the engine problems. If you could leave a # i can reach you at or call me at 414-899-7967 it would help me greatly.
Thank You Rich Colano"
 
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