Thread subject: Whaler Central - Boston Whaler Boat Information and Photos :: Guardian 100hp Prop Question

Posted by edmaude on 10/28/09 - 2:27 PM
#1

Folks,

I currently run an OMC aluminum 13 1/4 x 17 prop on my V4 100hp on my Guardian. It moves the boat ok and I top out at about 39mph per GPS with just me on the boat, approx 12 gallons of fuel and flat water. Hole shot is good and all in all it seems well matched to the added weight over the standard Montauk hull, which is 300lbs extra glass etc.

My prop got a nice dent in it due to my trailer getting knocked off the blocks I had it on for winter storage and the lower unit got plugged into the muddy mess below and one of the blades took the hit and has a 2 inch dent in it, which sucks.

I would like to see if anyone may have a better suggestion for a replacement. I know stainless is the best way to go, but I am not sure if it is worth the cost, vs getting a new aluminum prop on I boats for about 100 bucks. We don't tow skiers and generally use the boat for cruising and fishing etc

Ed

Posted by whalerman on 10/28/09 - 4:25 PM
#2

Hi, just to be on the safe side I would have the prop shaft checked to see if it's bent. Very easy to do as far as setting up a dial indicator and rotate the shaft to see if there is any deflection, wobble, probbly isn't any but peace of mind knowing any way. I know what you mean about the ss props as it took me awhile to fork over for one. But since I have I wouldn,t go back to alloy, only in emergency. I had a 21"pitch with a 115 hp johnson on a 17' sport, not quite as heavy as yours. Yea, it hauled butt to, had to be very carefull with her at wot. You found a very good looking whaler. Did you up the oil tank in a box so it's out of the weather? The boat should last you for awhile. If I'm not mistaken the 100 hp commercial motors were fitted with v6 gearcases.

Edited by whalerman on 10/28/09 - 4:56 PM

Posted by edmaude on 10/28/09 - 5:47 PM
#3

Thom,

Thanks for the insight. I actually ditched the whole VRO system this year and went to a straight OMC fuel pump and premix, which was about 1/4 the cost of a new VRO unit and now no more tank taking up room in the stern etc. I have a v4 lower unit on the engine, which I imagine may have been changed out at some point in the past. My season was over, but now I want to get everything in check prior to spring so may take her back out again if I have the time

Posted by joninnj on 10/29/09 - 5:18 AM
#4

Hi Ed,

Just as a frame of reference use a 13 X19 K series stainless on my 17. I have a Yamie 90 with 2:1 gear ratio. I can squeeze 5200 RPM with a lighter load. I am also mounted flush on the transom.

For the short time I was able to hold a GPS, steer, and manage the throttle I saw 42PMH at 5100. I know this is an apples and orange comparison, but you should be able to squeeze a bit more out of you 100. Your engine is prop shaft rated? All of them from mid 80's on were.

I will pulling my 17 out on Sunday, If you are still in the water around we could check it out. I would definitely get a stainless. I purchased mine new on ebay for $150 from a dealer in the south who had a bunch of these.

Edited by joninnj on 10/29/09 - 5:23 AM