Mercury High 5

[butlp]

Just a word of warning to anyone thinking of investing in a high priced Mercury prop, watch out!<br /><br />I ordered a new rig with 115 Optimax in the spring and told my dealer I wanted a High 5 prop. I had run the numbers through the Mercury prop sizing program on their web site and it specified a 20" pitch High 5. My dealer said another option was a 22" Laser II and I assumed the 22" was selected because he had experience of the motor/boat combination. I went with the High 5 and assumed that 22" was the correct pitch and the dealer did not question this when I placed the order with the rig.<br />The boat was a dog, struggled to pull 5000 rpm with one person in the boat.<br />I called the dealer and asked him to exchange the prop for a 20" but he informed me it was mine and could not be returned. In Canada, Mercury only has a few dealers that subscribe to the "Prop exchange" program which allows you to test the prop before you purchase it. I contacted Mercury Canada and they told me to put the 22" on ebay and hopefully I'd get 50 cent on the dollar.<br />To cut a long story short; after a lot of finger pointing and me getting high blood pressure Mercury Canada agreed to exchange the 22 for a 20 as long as the prop was in perfect shape.<br />The 20" is a lot better but still only turns at 5200 rpm and is not as quick out of the hole as I had hoped, plus it's the smallest High 5 available for my motor. Now I'm looking for a 17" or 18" Lasor II on ebay

 

[LubeDude]

Re: Mercury High 5

Sounds like your dealer isnt very well informed. The high five is a hole shot prop, you would have posably been better with the Lazer. Maybe your engine is mounted a little low and you can use the one you have. Your ventilation plate should be at least 1" above the bottom of the boat.<br /><br />Give us the details about your boat, also, give us the #s you are running now. Do you have ventilation holes in your prop, I think all the high fives have them though. You could drill them or make them slightly bigger.

 

[butlp]

Re: Mercury High 5

The plastic ventilation plugs are still installed in the prop and I should pull them before doing anything else.<br />The boat is a 16'-6" bowrider (1100lbs) and the motor is a 2005 115 Optimax (WOT 5000 - 5750). According to the boat instrumentation, with one person, half a tank of gas and normal gear the WOT is 5200 and speed is 49 to 50 mph.<br />My problem is that the boat does not come out of the hole as well as my old boat with an old 90 Yamaha. When you buy a new boat you expect better performance than the old package. The dealer did water test the boat before I picked it up and he felt it ran well, however he told me the tach was not functioning properly and had shown 10,000 rpm during the water trial.<br />The motor now has approx 60hrs + and has been fantastic, very frugal on gas and oil, no smoke and very quite.

 

[LubeDude]

Re: Mercury High 5

We have all of the information we need except the hight of the engine on the transom. Put the engine in a level with the bottom of the boat position and look to see where the ventilation plate is to the bottom of the boat. Its likely slightly below or even with the bottom. It can be raised to at least 1 inch and maybe as much as 2 inchs from the bottom. This will give you 2-300 RPM more at WOT. That with the removal of the plugs may put you right in the ball park. Is your WOT RPM figure with the engine trimmed out all the way?

 

[WillyBWright]

Re: Mercury High 5

You seem to make the erroneous assumption that a SS prop is a SS prop is a SS prop. Each design has it's strong and weak points. And to kvetch so fervently without doing even the least bit of experimentation with those vent plugs means you need to do a lot more trying and a lot less complaining.<br /><br />3-blade props need to stay completely submerged. 4 and 5-blade props can pierce the surface of the water and still stay hooked-up. That allows you to lift the motor higher on the transom. That means less gearcase in the water. Less drag. More speed.<br /><br />It's not likely the wrong prop that's your problem. It's the set-up of the motor.

 

[walleyehed]

Re: Mercury High 5

I will agree the set-up needs attention...I do not agree that a 3 blade prop should stay under the water...<br />It all depends on the cup, Rake, etc.. run the prop where it performs best on that boat. I run my 3-blade Raker and Turbo about 3" out of the water...AV plate is about 4" above the water.<br />Another quick note...If you use the Merc prop finder, plan on 2" less pitch than what it recommends...I have not seen 1 single case where it was correct, ever.<br />22 in a 3-blade is not the same as a 22 in a 4-blade...nor is a 22 of a different manufacturer the same as a 22 Merc prop.

 

[butlp]

Re: Mercury High 5

WillyB,<br />I don't think I'm complaining but trying to warn other members that when it comes to Mercury SS props you're on your own, which I think is wrong. I'm not making erroneous assumptions about SS props, I realize they are different from alloy and SS 3/4 blades, the only assumption I made was that the dealer and Mercury Canada know which is the correct prop for my set up and if they don't then let me return it if it's incorrect!<br />If you had spent 25K on a new boat that was prepped for a Mercury O/B and supplied with a Mercury SS prop you would expect the motor hight and set-up to be right from the dealer, he's the expert If I had been told at the time of purchase if the prop was wrong it was mine to keep, I would have not spent the $500+ and stayed with the standard cheap alloy three blade. If you can find a dealer that will lend you a prop (they will never let you try the High 5) you're still guessing as the 5 blade is so different.<br />

It's not likely the wrong prop that's your problem. It's the set-up of the motor.

I don't have the equipment to raise a 400 lb motor on a brand new boat and the dealer and Mercury never suggested this as a fix or offered to help. They both said it was all my fault because I had specified a 22" pitch prop in my e-mail purchase order and I should live with it.<br /><br />LD, Walleyehed, Thanks for the constructive replies, I'm in Mexico this week but will be back at the lake next week and will measure the engine hight plus pull all the plastic plugs and report back.

 

[orca]

Re: Mercury High 5

I think your problem is not with your Motor or your prop, It is with your dealer.<br /><br />Every dealer that I have been involved with has been more than happy to exchange props. In fact most dealers will test run and make sure that the prop is correct before delivery<br /><br />Motor height is very important, the correct height for a 3 blade prop is probably not right for a 5 blade.<br /><br />Mercury have an interesting publication called 'Everything you need to know about propellers' that is worth getting hold of.<br /><br />It is up to the dealer to make sure that the motor is set at the correct height and has the correct prop.It is not up to Mercury to sort out the dealers problem, maybee they should be sorting out a problem dealer.

 

[LubeDude]

Re: Mercury High 5

Lostcanadian:<br /><br />We are going to make sure your experience with boating is a good one.<br /><br />First off, no boat, engine, or prop book on earth is going to nail your set-up perfectly, Its allways a crap shoot, but your dealer should step up to the plate and make sure your boat is right. Sounds like you made the recomendation instead of the dealer. Maybe you insisted on the highfive over what he offered, not sure, anyway, lets get it right for you, enjoy your trip, we will be here when ya return.<br /><br />Listen to Walleyehed, hes the prop guy along with Dhadley.

 

[moderator1]

Re: Mercury High 5

Moving to the new "Prop questions and Topics" forum in the General boating section...