MD2030 lost of speed

[Tin Tin]

When you dove under the boat did you open and close the flexofolds, they should move easily, if not try working some water proof grease in there and work them open and closed, could be barnacle or something in the teeth like fishing line etc too. Then with boat in gear try opening the blades and turning the prop, if it moves more than an inch you may have a hub or clutch problem. There is a rubber bushing inside the flexofold hub.

[sailaboutvic]

Originally Posted by Tin Tin

When you dove under the boat did you open and close the flexofolds, they should move easily, if not try working some water proof grease in there and work them open and closed, could be barnacle or something in the teeth like fishing line etc too. Then with boat in gear try opening the blades and turning the prop, if it moves more than an inch you may have a hub or clutch problem. There is a rubber bushing inside the flexofold hub.

Prop blade are free
There no rubber inside the hub , spoken to flexfold

[skipperpete]

There are several phone apps that use the flash to measure Rpm…. and do it very well too.

[sailaboutvic]

Originally Posted by skipperpete

There are several phone apps that use the flash to measure Rpm…. and do it very well too.

Can you point me to one , I just downloaded RPM meter strobe light and cab
Not figer out how it works . More ad then anything

[sailaboutvic]

Now manage to check shaft speed .
It match’s up with what it should be give or take 10 rpm .
So it can’t be the gear box .
Don’t leave much .

[team karst]

Good rotational speed but low forward thrust. Weird problem. Any chance air is getting to prop causing ventilation? Is shaft/prop connection standard taper with keyway? Maybe sheared key?

[sailaboutvic]

Originally Posted by team karst

Good rotational speed but low forward thrust. Weird problem. Any chance air is getting to prop causing ventilation? Is shaft/prop connection standard taper with keyway? Maybe sheared key?

Sheared key is something I tho of but it’s a big key ,I won’t discount it but I be surprised.

[sailaboutvic]

Here a up date ,
From my posting #21
I been in again to check the prop ,
The three blades open with easy just using my finger tips ,
Couldn’t find any play .
Open and close them several time with a bang in case there anything in between the gearing .

So now I’m totally lost ,
The shaft RPM matches what the Manuel says at engine set speeds .
Propeller seems fine , blades no chips and clean

[team karst]

Engine OFF, in FWD gear. try to manually turn prop after you extend a couple blades. what happens?

[sailaboutvic]

Originally Posted by team karst

Engine OFF, in FWD gear. try to manually turn prop after you extend a couple blades. what happens?

I glad you said engine off , I was getting worried you had enough of my problem and trying to get rid of me

To be honest I not tried that ,maybe next time I’m in the water I give it a go .
But I be shocked if the key as snapped.

[team karst]

Not as shocking to have the friction clutch plates slipping. I need to dive both my MD2030 to scrape props...maybe today.

[sailaboutvic]

Originally Posted by team karst

Not as shocking to have the friction clutch plates slipping. I need to dive both my MD2030 to scrape props...maybe today.

I now very doubt it’s the clutch .
I tested the shaft rpm at engine rpm 1500, 2000,2200,2500,2800 and it tally up to what it should be give or take 10 rpm

The only other thing is the woodruff key prop side .

[skipperpete]

I agree about the transmission not slipping knowing that the rpm matches and the oil is ok. Of interest, I have the same engine and gearbox in a fat little Viksund sailboat and at 2500 rpm I make just on 5 knots.

[Dalestr]

The VP manual says to use Dextron 2 or 3 ATF for transmission. Don’t use anything high tech here which could cause slippage. Verify full travel of shifter cable, can try running with cable disconnected if in doubt. Check that propeller is opening fully and easily without barnacles in the gears.
A clutch slip causes heat up of the transmission as the clutch absorbs lots of engine power. This could be masked somewhat if you have the water cooled option, which can be unbolted from the side.

[alla breve]

Just in case- where are you measuring shaft speed? Before or after the coupling?(Coupling slipping?)