Quickie for Dhadley

[CATransplant]

Re: Quickie for Dhadley

Fireman,<br /><br />Where is the AV plate in relation to the bottom of the transom?

 

[Dhadley]

Re: Quickie for Dhadley

Good. It responded to the height. I'm sure the holeshot is a product of some wear on the prop. Obviously it wont hurt to try the other 1/2" is possible. <br /><br />I know you told me once but I cant find it. How many splines?

 

[fireman57]

Re: Quickie for Dhadley

CAT, AV plate is about 1.5 inches above. Dale, if I try the other 1/2" it will put me at the top edge of the transom. with the block of wood under the bracket I don't want it to be to unstable and rock off the boat since I did not drill a new hole for my safety bolt. 14 spline, thru hub exhaust. I am going to try to get out tomorrow am for a while. I will go up the 1/2" if it won't cause problems. My H2O intake is right below the water level now at WOT.

 

[CATransplant]

Re: Quickie for Dhadley

I wouldn't raise it any further, Fireman. If the water intake screens are almost at water level, you'll be sucking air on turns, and that's not a good thing.<br /><br />Add the instability of having the motor mounted so high...almost off the transom, and it sounds unsafe to me.<br /><br />If you only gained 100 rpm by raising the motor an inch, and can't go any futher, and you're still running just over 4000 RPM, I can't imagine that you're going to pick up much more with another 1/2" anyhow.<br /><br />To me, this sounds like the wrong prop for your rig. I know Dhadley wants to fix this with setup, but I don't think it's going to work. I think you're just flat over-propped.<br /><br />My 35 turns a 10x13 just fine and RPMs at WOT are right where they should be. Your 25 isn't turning the 10x13 all that well, and is way under it's maximum RPMs.<br /><br />If it were me, I'd try my darndest to borrow a 10x11, drop that outboard back down on the transom, and see what transpires.

 

[fireman57]

Re: Quickie for Dhadley

Actually I like where it sits now. The propwash isn't as heavy and it gets out of the water better when on plane. I've read too many posts by Dale and he seems to be the best on setup. I like the way that he thinks like I do. Get the most out of what you have first then you know where to go next. I think the main problem is that we're working with a prop that has just about had it. I'm going up the other 1/2" and adjust my smart tabs back down a hair for planing. If pick up 200 rpm per inch I almost need to go to an 11x9 if it will turn an 11. Can't find a 10x9.

 

[CATransplant]

Re: Quickie for Dhadley

Go for it! Let us know what happens.

 

[Dhadley]

Re: Quickie for Dhadley

The plan is to make one change at a time. We could have started with a new prop but I hate throwing money at something. The hull responded about as we hoped for. If going up another 1/2" makes the mounting unstable, then dont do it. With safety in mind we always try to test past optimum and then back up slightly. <br /><br />I have a 10 1/2x11 Turbo at the marina that we should try. Now, the only thing about that is I'm sure it will bite better but we may be limited on height. Just for kicks check out the "Mini Jackplate" from Bobs Machine. They probably sell them here. I'm not saying we have to have it, just check it out and see what you think.

 

[fireman57]

Re: Quickie for Dhadley

Well the extra 1/2" was a little much as I would break loose even on a sweeping turn. Only picked up about 50rpms. As far off as I am from 5000 wouldn't I be better dropping all the way to a 9" pitch? Just myself in the boat I can get 4400 now. Problem is my normal load is about 400lbs more and it makes one heckuva difference. Last night I had myself (175) my son (150) his friend (270) and a nephew (165). That totally maxes me out and I know tht no matter what I do with that much weight I will neer get going without more horses. I'm looking to get the boat out of the water with three people (600) and my rpms around 5000. If I have less I can always back my throttle down so I don't over rev.

 

[fireman57]

Re: Quickie for Dhadley

The mini jackplate here looks pretty neat. The only thing is that I will probably land a 50hp this winter and wouldn't need it then. If I can get through this summer/fall I should be in good shape. I have a white bass/striper trip in two weeks and another one for a week in July. Just want to be able to get across the lake safely and fairly quickly.

 

[fireman57]

Re: Quickie for Dhadley

bump

 

[Dhadley]

Re: Quickie for Dhadley

Good plan. If youre going to change the motor are you still thinking about changing props on this one?

 

[fireman57]

Re: Quickie for Dhadley

Dale, yeah I am going to change props on this engine for two reasons. First it's beat to hell, second, I need to get this engine up to rpms. Would like to just buy one. Question is would you go with a 10x11 or and 11x9? Also will I be able to turn an 11/9 without much trouble? Also I can't seem to get an answer on pitch. I am guessing that I should get about 200rpms an inch. I'm about 600 off. Is this right? Thanks.

 

[Dhadley]

Re: Quickie for Dhadley

Thats the rule of thumb when comparing 2 new, same style props. 200 rpms per inch, all things being equal. However (dont ya love those?) in some cases you may change to a prop that has more lift so you reduce drag and actually pick up more than the 200 per inch. Or you may switch to a prop that has more bite and lose rpms. Thats why testing is so important. <br /><br />A couple of other things -- the Turbos I have are 13 spline and only go down to a 12 pitch. I dont think the props I have are going to do us any good.

 

[CATransplant]

Re: Quickie for Dhadley

Fireman,<br /><br />Be sure to let us know what you decide and what happens when you test it. You've tried a lot of stuff. Looks to me like a new prop is in order.<br /><br />Personally, I still think the 10x11 is going to work for you, but that's just my opinion. Dhadley obviously knows a lot more about this than I do.<br /><br />I'm just working from my own experience with a 35hp on a boat of similar size. Mine spins a 10x13 stock OMC prop, right up to the rated RPM.<br /><br />You have a 25hp motor with the same prop pitch and diameter. It doesn't reach rated RPM. Same-sized boat, although you haven't described the type of hull or weight.<br /><br />Will the 10x11 get you up to rated RPM? I don't know, to tell you the truth, but I'm certain it will get you closer than you are now, as I've suggested before.<br /><br />You're not racing this boat...you just want it to run closer to its rating and get out and go fishing. It's not a critical thing, and you're not going to destroy your outboard, regardless.<br /><br />Since you're going to replace the outboard after this season, I'd just grab a reasonably-priced aluminum 10x11 prop, mount it, put the old prop in the boat as a spare and get out on the water.<br /><br />Once you get your 50, then it'll be time to fine-tune your system for maximum performance. Right now, I'd be going for maximun usability and minimum stressing out on this. But that's just me.<br /><br />Time to go fishing.

 

[CATransplant]

Re: Quickie for Dhadley

Oh, yeah, I see that Vortex also has a 10.5x10 prop for your outboard. I found it here on iboats using the prop search. That's another option, and I also see that the 11-pitch props are all 10.5, too.<br /><br />It's your call, I think. You can get the thing for about $60, in any case, so it's not a huge expenditure, really.<br /><br />If it were me, I'd pick the 10 or 11-pitch one, order it up and get back on the lake. Either way, I'll bet you outrun your brother's boat.

 

[ross patti]

Re: Quickie for Dhadley

Hey,fireman...<br /> How did the test go ??

 

[fireman57]

Re: Quickie for Dhadley

Well all the first test didn't do so well. Prop came when they said it would which was Friday afternoon. Put everything together in a hurry to get out on the water. When I fit it on the skeg it sat aout avout 1/3" farther than my old prop did. Used the brass bushing that came with the prop. Launched and gave her some juice and it bit well but broke loose almost immediately. Thought there is no way that the hub was spun already but that is what it acted like. Pulled her back out and put old prop on as brother and wife were with me to go fishing. Yesteray I took it back off tried to figure it out. I have marked the hub but not had a chance to try it with the rain. I did get a stainless washer that fits in where the bushing was and it fits well in the hub of the prop. The only thing I am concerned about it that it is not beveled to fit on the shaft. It just hits the shaft about 1/2 way up the bevel on the shaft. The prop now fits on the skeg all the way like the old one did. I was amazed at how much of my old prop was gone compared to the new one. It is only about 2/3 of the original size.

 

[CATransplant]

Re: Quickie for Dhadley

Which prop did you end up buying?

 

[fireman57]

Re: Quickie for Dhadley

10x10.5 Looks like rain all day today also. I'mjust afraid that the stainless washer will end up cutting a ridge on my prop shaft bevel. The new prop looked like it was on the splines all the way. My old prop had a soft washer that fit over the splines at the very end of them. Could not use it with the brass shim that came with the prop.

 

[CATransplant]

Re: Quickie for Dhadley

I wish I could help with that, but my experience is all with the shear pin drive props. Something doesn't sound right with that prop's fit, though. I don't know if something's not there or what, but I don't think I'd jerry-rig this thing. Your instincts are correct.<br /><br /><br />I hope someone's here today, Sunday, who can advise you.