WTH do I do with this?

[ageless]

My 55c was missing 200-250 RPM's under load, heavy soot on
transom and the horizon. Had props pulled, shop calls to inform the port wheel is 27x28, the starboard 27x30. I did note the starboard was slower to accelerate, by tach, but at wide open port was 2100, starboard 2150. Recommendations on where to go with these

[krush]

take both to 27x29 ?

[doc g]

didn't you just buy this boat?? ....and talk to a prop shop and other 55C owners before changing anything . I would think you need to get rid of pitch on both to get 2350 rpm. I thought each inch = about 50- 100 rpm at WOT?? .....Pat

[ageless]

didn't you just buy this boat?? ....and talk to a prop shop and other 55C owners before changing anything . I would think you need to get rid of pitch on both to get 2350 rpm. I thought each inch = about 50- 100 rpm at WOT?? .....Pat

they are at the shop, they discovered the difference. It's just weird that the 27x28 only reached 2100, the 27x30 2150, the bigger prop spun up higher

[Avenger]

Did you verify that your tachs are accurate?

[racclarkson@gmail.com]

My 55c was missing 200-250 RPM's under load, heavy soot on
transom and the horizon. Had props pulled, shop calls to inform the port wheel is 27x28, the starboard 27x30. I did note the starboard was slower to accelerate, by tach, but at wide open port was 2100, starboard 2150. Recommendations on where to go with these

You using a really good prop shop? A good prop guy has forgot more than we'll ever know. If you're not sure, put the job on hold until you have confidence in them or find someone else. I grabbed my props away from the best guy around in Ft. Meyers when I found out he was the best guy around on outboard props. The boatyard made a recommendation on what was in their best interest and not mine.

Don't worry too much about other 55's. Tell the prop shop what your expectations are relative your concerns. Ask them if they think they can achieve the goals. Settle on an agreed upon level, and ask what happens if the performance falls short.

The minute you tell them how you want your props pitched or balanced or cupped is the point where you absolve them of any responsibility other than doing exactly what you told them to do.

[doc g]

If that's so I would suspect engine issues, the "under"- propped side could be pulling the "over"- propped side down(rpm -wise) too, why would you not have the same props on both sides????

[Bob Bradley]

The fact that the bigger prop spun higher makes me think it might be more than just unmatched props that is causing your soot and lost rpms. Have you verified that all your injectors are firing? Are the airseps (if so equipped) clean and supplying air? Might you have a turbo outlet tube that is leaking past a hose? Is it aftercooled, and if so, is the aftercooler clean?

I'd hate to see you change the pitch of the props and reinstall them on improperly running engines. Big waste of fuel and efficiency (speed).

[ageless]

Did you verify that your tachs are accurate?

supposedly confirmed with photo tach during survey

You using a really good prop shop? A good prop guy has forgot more than we'll ever know. If you're not sure, put the job on hold until you have confidence in them or find someone else. I grabbed my props away from the best guy around in Ft. Meyers when I found out he was the best guy around on outboard props. The boatyard made a recommendation on what was in their best interest and not mine.

Don't worry too much about other 55's. Tell the prop shop what your expectations are relative your concerns. Ask them if they think they can achieve the goals. Settle on an agreed upon level, and ask what happens if the performance falls short.

The minute you tell them how you want your props pitched or balanced or cupped is the point where you absolve them of any responsibility other than doing exactly what you told them to do.

The shop I'm using was chosen after personal research and interviewing. They have props that are 6' in diameter, do all the work for the port in Wilmington. He mentioned one prop may be pulling the other down, they had a small amount of scale build up to remove and would work them to match. All I have told them is I need 200-250 RPM's, we'll see how things go when I call in AM

If that's so I would suspect engine issues, the "under"- propped side could be pulling the "over"- propped side down(rpm -wise) too, why would you not have the same props on both sides????

Prop shop mentioned one pulling the other down, good question why they're different, not happy that my survey says "reported 27x29"

The fact that the bigger prop spun higher makes me think it might be more than just unmatched props that is causing your soot and lost rpms. Have you verified that all your injectors are firing? Are the airseps (if so equipped) clean and supplying air? Might you have a turbo outlet tube that is leaking past a hose? Is it aftercooled, and if so, is the aftercooler clean?

I'd hate to see you change the pitch of the props and reinstall them on improperly running engines. Big waste of fuel and efficiency (speed).

The prop work is being done based on recommendation from survey. I have not been into the injectors, airseps were cleaned in April, motor is intercooled

[Cricket]

I would have the engines gone through before having the wheels modified. Did you have an engine survey done? If yes was it a DD guy or survey guy? April doesn't really mean anything, how many hours since cleaning, same for the fuel filters, etc.