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Mercury 60HP 4-stroke Lower unit gearing

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Mhalkett10

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I purchased a 2016 Mercury 60HP 4-stroke with a damaged lower unit which had “12 x 22 and 1.83:1” stamped on it, I purchased a replacement with “13 x 26 and 2.00:1”, I am having issues getting my boat (2016 princecraft holiday dlx WS) to plane with any more than two people and gear on it, cruising speed is fine once I do plane out and the tach reads at about 6200 rpm at WOT (which I know is a bit high) with no audible beeps. My question, is the 2.00:1 my new gearing or can the parts be interchangeable, and how does this impact holeshot and top speed, which I think would decrease holeshot but improve top speed performance, please help, thank you
 
The 2:1 spins the prop slower as it takes 2 full revs. of the crankshaft for one rev. of the prop whereby the 1.83 only takes 1.83 turns. With that said, the 2:1 has essentially reduced the pitch of your prop which should give you a better hole shot and load carrying ability.....plus the undesirable effect of possibly over revving which you mentioned.

The confusing thing about your post is that you are indicating problems at both ends of the prop pitch spectrum....you say that load carrying performance getting on plane is hindered (too much pitch) and once on plane exceeding RPM max. (too little pitch)??????
 
I am using a spitfire 4 blade prop measuring 10.1” with a pitch of 15, while using the mercury prop selector it suggests a pitch of 12, 13 or 14 in the 1.83 gearing, and a pitch of 17 in the 2.33 gearing, I think I would want to pitch down to increase holeshot performance but this would cause rpm to go beyond 6500. I have not ruled out that the tach could be off as there are no audible alarms when it reads 6200-6300 rpm with current prop.

I guess I can prop down to 12 or 13 and back off the outboard a bit to reduce rpm, I just don’t want to try too many props as they are $400 each in northern Canada.

The original damaged prop was a spitfire 10.3 x 13 pitch, and I don’t know how it performed then, and I purchased a 3 blade at 10.13 x 15 pitch with the same undesirable effects.
I can also get a new tach or have it calibrated so that the guesswork is halved,

The boat performs beautifully if I am alone or with one other person, but we have a family and I need that extra performance.

Thanks again, I know this is complicated
 
Having tach problems makes a lot of sense. That would explain the paradox I mentioned.

A 60 isn't a powerhouse and loading up the boat with folks doesn't go well. In my boating circles, back in the '60-70 time line friends with 15' light weight tri-hulls did OK with 2 folks running a 60-65 HP OMC looper but trying to tow water toys and all you had to keep the passenger count low.
 
One other question I had was would the original 1.83:1 gears fit it this housing that is stamped 2.00:1, which upon searching looks like it came off a 40hp outboard, or can I assume that they are 2.00:1?

I may remove and inspect the lower unit and cross reference the part numbers on the gears to confirm, but not till after the weekend.

I may also cave and purchase a spitfire 10.6 x 12 to get the holeshot I want. Im taking the boat out this weekend and will report back.

Any other suggestions would be greatly appreciated
 
I purchased a 3 blade Black Max 10.6X12P, I tried out the new setup on Reindeer Lake, Saskatchewan, a big lake with big water. I had the boat loaded with 4 people, 45 gallons of gas, and a couple hundred pounds of gear. I was able to get on plane very easily and reach a cruising speed of 29mph. I am very pleased with the result.
 
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