Drive advice needed - Starboard Velvet Drive failed

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tdogg
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Re: Drive advice needed - Starboard Velvet Drive failed

Post by tdogg »

Update: Pulled the starboard drive, had to take manifold, alternator, etc off and pulled it right out the main hatch.

took the boat out this weekend on one engine (getting pretty good at it, but definitely easier to drive with two :) )

Unfortunately I'm noticing the other drive slipping, so it looks as though I'm going to have to remove them both.

I do have the other drives (1:52:1 ratio) that are in working condition. I know I'll need to replace props, but I have been looking to go with 4 blades. Is there a glaring issue going this route? This will get the drives in sooner rather then later due to fixing them. Then I could fix them and have them should I need them in the future.

As always your insights are greatly appreciated.

Cheers,

TDogg
1987 Trojan F36 Tri-Cabin
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prowlersfish
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Re: Drive advice needed - Starboard Velvet Drive failed

Post by prowlersfish »

You will have to go with a lot smaller prop
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WayWeGo
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Re: Drive advice needed - Starboard Velvet Drive failed

Post by WayWeGo »

To add to prowlersfish's response, smaller props will not do as well at slow speeds.

Our props are smaller than stock and I often have to use some throttle to get the boat to respond when docking. Larger props would help with this and I will eventually swap them out.
1975 F-36 Convertible
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tdogg
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Re: Drive advice needed - Starboard Velvet Drive failed

Post by tdogg »

WayWeGo wrote: Tue Jul 10, 2018 10:26 am To add to prowlersfish's response, smaller props will not do as well at slow speeds.

Our props are smaller than stock and I often have to use some throttle to get the boat to respond when docking. Larger props would help with this and I will eventually swap them out.
Thank you for your posts WayWeGo and Prowlerfish.

I have thought our props were undersized. they are 20" with 15 pitch. we mainly drive at slow speeds.

WayWeGo what drives do you have? prop size?

our boat is a 36' tri cabin. really want to get two drives in as soon as possible so I can enjoy the boat more this season with less maneuvering stress.

what size props would be recommended? we have crusader 270 HP engines
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WayWeGo
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Re: Drive advice needed - Starboard Velvet Drive failed

Post by WayWeGo »

tdogg, we have 18.5" x 19" props with no cup. The F-36 convertible came with 20" x 21" props and 1:1.91 Velvet Drive transmissions.

Our boat came from the factory with 400 cu in Chryslers, but the previous owner put 440's in. Perhaps that has something to do with the smaller prop size, but I don't know. He did have the props re-pitched to 20", but went back to 19" the following year.
1975 F-36 Convertible
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prowlersfish
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Re: Drive advice needed - Starboard Velvet Drive failed

Post by prowlersfish »

tdogg wrote: Tue Jul 10, 2018 4:47 pm
WayWeGo wrote: Tue Jul 10, 2018 10:26 am To add to prowlersfish's response, smaller props will not do as well at slow speeds.

Our props are smaller than stock and I often have to use some throttle to get the boat to respond when docking. Larger props would help with this and I will eventually swap them out.
Thank you for your posts WayWeGo and Prowlerfish.

I have thought our props were undersized. they are 20" with 15 pitch. we mainly drive at slow speeds.

WayWeGo what drives do you have? prop size?

our boat is a 36' tri cabin. really want to get two drives in as soon as possible so I can enjoy the boat more this season with less maneuvering stress.

what size props would be recommended? we have crusader 270 HP engines

What speed and rpm are you getting at Wide open . If you change gears to 1.5 to 1 you will have to go even smaller
Boating is good for the soul
77/78 TROJAN F36 Conv.
6BTA Cummins diesels
Life is to short for a ugly boat :D
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