boat won't plane

[902dlw]

We have a 2002 Albin 36, purchased last summer. Being a new but used boat, we have found that several things needed to be done. We replaced the dry exhaust elbow and after-cooler, serviced the wet exhaust elbow, flushed the cooling system, and changed all the filters and oil. A diver cleaned the bottom and checked the prop and cutless bearing and found no problems. We took it on a sea trial after the work was done. The engine reached it's maximum of 2,600 rpm, but would not exceed 10 knots or get on plane. The turbo charger has been found to be ok. We are stumped.

Barry and Vicki Lathom

[jleonard]

What boat model is it?
If it's a "classic" 36 it likely won't plane.

[RobS]

What boat model is it?
If it's a "classic" 36 it likely won't plane.

It's not the classic 36, it's a 36 ET, he posted in the wrong section. It is a planing hull and with a single I believe she should get on plane and hit about 14 to 15 knots.

So you are hitting your rated rpm ?

[902dlw]

Rob: it is a 36 ET and it's hitting its rated rpm -- 2600. We've had it at 15. Not used to his forum, so didn't know I posted on wrong section.

Vicki

[RobS]

So she's hitting the same RPM as she did from day 1 but you lost 5 knots?

[Tree]

Loss of cup on the propeller through wear?

[RobS]

Is there a trolling valve installed ?

[jleonard]

Are you sure about the true rpm? Has the tach been calibrated using a hand held?
Did you change the alternator? (that could put the tach out of cal)
Have you added weight to the bow? (ie anchor chain)

[902dlw]

RobS. Yes runs same rpm, but lost 5 knots. No trolling valve.

Tree: loss of cup through wear? Checked by diver. Haven't had boat pulled.

jleonard: Mechanic checked rpm. Tach has been calibrated. No alternator change. No new weight.

Thanks.

[Tree]

This may sound silly, there is no chance that the key on the propeller has shifted and the propeller could be spinning on the shaft?

Propellers do wear, the blades become thinner over time and less efficient but re reading your original post this I guess can't be the case.

There's nowhere on the boat that water could have collected? Though saying that, one would assume that you wouldn't be able to get WOT unless of course you were under propped to start with.

To have lost 50% of your overall speed in such a short time would indicate that it's something to do with transmissional losses. Can you give the details of your setup, engine, gearbox, propeller diameter & pitch etc?

[902dlw]

Tree: Good thought. We're going to have the prop checked for whether the key is compromised or just not there for some reason. Something might have happened after the prop was serviced after going aground coming down the ICW. We have no idea of the quality of the labor. We had the boat short hauled this am and no one considered this possibility.

Also, we are going to check the transmission-- also for "slippage" at higher rpm.

[Tree]

Any update on this?

[James Grant]

LOL !!

[902dlw]

Update. We removed the dingy and motor from the swim platform and then we were able to get it on plane.

[jleonard]

Ahhh, the added weight put the boat out of trim. We knew there was a key somewhere.
Glad you figured it out