View Full Version : Inboard shaft clarification

04-14-2008, 06:11 PM
"Hello fellow boaters and hope everyone is about ready for a fun season.
My boat is a 91 CARVER 33 AFT CABIN with 454 Crusaders.Had it now 2 years and as I was told by others and including is the survey of the boat stating I have 1.5" shafts.My friend with a similar size TROJAN told me he had 1.25" shafts.When I left to come home last night I used a dial caliper to measure and we both measured in at 1.375(1 3/8")...My props measure 1 3/8" at big end, lets say, and 1 1/8" at small.Over the winter I picked up at a set of props in great shape, really cheap,thinking I had 1.5", but actually are 1.5 tapering down to 1.25......Am sure they will go on till they get tight,maybe a bit forward and will have to see about possibly a washer at the nut end.Can always sell these props if they are not a good idea.No biggy.
Paperwork for the boat is inside it over an hour away and thought I would run this by my boating friends here so I can learn, and know just what I actually have...In my mind I have 1.5" shafts....Todd Moore"

04-14-2008, 06:40 PM
If your shafts measure 1 3/8" then you have 1 3/8" shafts. 1 1/2" shafts will measure 1 1/2". Quite a few old Chris Crafts used the somewhat oddball 1 3/8" shafting. With 454's you'd want larger than 1 1/4" to avoid whipping and potentially torquing them in two. Perhaps your buddy has small block engines? That would explain a difference. Or perhaps he has measured wrong.

1.5 props can still be used on the smaller shafts with the use of a tapered shim made just for that purpose. Any good propeller shop will have them for you. Just using washers to push the props further up the shaft isn't a good idea.