I have an 86 Switzer, 86 175 Merc, 2" up on transom, running 28"
Hooter 3 blade and running 68mph with unsafe up trim causing lower
gearcase blowout. I am considering either raising the motor up a hole at a
time seeing what happens or buying a Hydraulic jackplate. What do you
think the right setback would be for the jackplate?
on your description I think going up will make it worse not better. I'd
try a 24 or 26 pitch chopper because the 28 at 68mph has to be slipping
like nuts. A good 24 at 6000 rpm should run there. It's possible the prop
is not a good combo for your hull. By trying a different prop we could
verify this. If you use less trim, turn less pitch but go faster then we
have found the problem. If it still won't run better, then next I'd go
lower or back on the transom. Try the prop switch first as it's the
Please submit whatever questions you have to IHRTechTalk@yahoo.com. All questions and answers selected will be displayed on this page as they come in. Note: though all boaters are welcome, priority may be given to I.H.R. members. Randy can not be held responsible for any advice given. Though his information and expertise is second to none, he has no control over what you do with your boat. It is up to you to boat safely and act responsibly, and his advice is only to be used as a guidance for your high performance boat/motor of which you are the one responsible for the risks involved.
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