TAMD 41B problem

Have you had any conclusion to this situation.

Sorry, I should have replied long ago!

In the end, the problem was solved. Again, it was a result of poor repair work, done by the (only) Volvo Penta-licensed shop around. When they replaced part of the exhaust system (removing the engine & leg in the process), and put the leg back on, they replaced the exhaust-to-leg bellows, but didn't bother to install a clamp on the leg end. As a result of steering, the leg end of the bellows came off the leg & folded over, almost completely blocking off the exhaust. This caused enormous back pressure and, of course, huge amounts of smoke. In addition, though, it gave a fairly free path for seawater to travel up to the turbo housing, allowing seawater to stay in there all the time (causing corrosion etc. of the turbo itself). In addition to all of that, the portion of the exhaust that did escape, while under way, emptied directly in front of the props, causing massive cavitation (and destroying the props in the process).

In the end, I found another (non-Volvo Penta certified) mechanic who discovered all of the above, and fixed it all. After a full hull cleaning, scraping & painting, the above repairs, and new props, we took it out for a run and got her up to 27.5 kts., which is more than 3 kts. higher than the manufacturer's specified max speed attainable.

So...bad service + repairs = around 5 1/2 months $ $7K to fix, but now (as of last October, anyway) it runs great. Hopefully, sitting in the cold Pacific since then hasn't caused any new issues!

Thanks for the reply! And after the exhaust being sorted out can you now get the required rpm´s from the motor. What is your wide open throttle rpm under load.

IIRC, I'm getting close to 3700 RPM before I pull it back. I can cruise comfortably at 23-24 kts. at 3400 RPM.

With the new turbo, it fairly jumps out of the water now - I swear, I could pull a skier out of the water! It used to take a looong time (20-30 seconds) to reach 2300 RPM, where the turbo would spool up, and the boat would surge forward. Now it does it in just 2-3 seconds. Engine is quieter & smoother, too. I guess I was lucky - my new-to-me mechanic was able to find & instal a NOS Volvo Penta turbo for around $400!