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What is 85hp's Speed?

2bboatman's Avatar

Join Date: Jun 2006
Posts: 1

06-30-06, 07:50 PM   #1  
What is 85hp's Speed?

Can anyone tell me what the speed of a 85hp Mariner outboard motor should be. I just go this used 16ft 1977 sea star and had it at the Marina for them to check it out and fix anything wrong with it and they said it was AOK after changing the plugs and cleaning the carb jets. I push the throttle foward to the stopping point and it runs about 15 miles per hour. Help1

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Pwrbait's Avatar
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07-01-06, 08:57 AM   #2  
There are a ton of variables here: First off, what is the boat rated for? There should be a sticker/stamp somewhere stating the max engine hp for that boat. Is the engine original equipment? Is the engine attaining full RPM in neutral, or did it get to WOT RPM in the test tank at the repair shop? Is it mounted on the transom with the correct amount of tilt? An outboard will always try to run vertical, so if the prop is to far under the boat, it will pull the bow down, and if the prop is to far away from the transom, it will raise the bow, causing speed and handling issues. Do you have the correct prop? Is the hull of the boat clean, you would be amazed at how much growth will slow a hull down, in your case probably not to such an extreme. These are just some of the questions that need to be addressed before anyone can start to troubleshoot your problem.

Ed Imeduc's Avatar

Join Date: Aug 2002
Posts: 18,389

07-04-06, 09:06 PM   #3  
Im with all the above post. When I get a used boat with a OB on it . It takes me about 6 months playing with it to get it to run top end. Even how high it is set on the transom plays a lot into it.


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