About 3 weeks I hit a rock pile with my lower unit. I have since put a new/used lower unit on my motor. Since then I have lost about 10mph on the top end. I had the prop fixed by the local prop shop it looks as good as new. I havent moved the jackplate or changed anything other than the lower unit. I was running about 65 or so on the top end, now I am around 55 or 56mph. 95 Eyra 2005 Mercury XR623p Tempest Plus5600 RPMAnyone have any ideas?
looks like a return trip to the local shop is needed. prop may look shiny and new but could be a different pitch than previous. A new/used lower unit could have its issues as well. Maybe the prop shaft is bent. There nothing that anyone is going to be able to pinpoint your problem without inspection. Therefore, I suggest taking it back to the shop. Lastly I would inspect under the hood as well. An impact with a rock can cause some things to work loose like spark plug wires! Good luck!
Thanks for the replies. The motor was checked out by the shop compression checked, trying to find all they could wrong with, it was an insurance claim. They are saying that the ratio of the lower unit may have changed.
BCB, could the replacement L/U be a different gear ratio? Jimmy make sure you get underneath and check the bottom of the hull. An untreated chip in the gelcoat can lead to big trouble.
It appears after some more studing and looking around and question asking that the mechinac pulled the motor off the jackplate for the insurance adjuster to look at the jackplate for damage, and remouted it 2 bolt holes higher than it was. BCB can you give me base line settings as far as setup and motor height? Thanks.
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