Idle and WOT Confusion

ledzeppelin135

Petty Officer 2nd Class
Joined
Jul 27, 2011
Messages
129
Hello, I purchased an 83 Mercury 50hp outboard and it seems to be running mostly good. With me in the boat is hits probably 35-40 in my 15 foot fiberglass 1959 Harvey which has a base weight of 430 pounds. Add 6 gallons of gas, a battery and two more 150 pound passengers and it is only going a max of maybe 10 mph and does not reach a plane. I have played around with the trim pin and found the middle pin out of six to be best fitting but when there are three people with gear on the lake at ten mph the engine easily looses half the rpm that it had with just me. I am wondering what I can do about this, I have checked and the throttle arm seems to be bottomed out but it just does not make any sense. Also, I am wondering what the deal is with my controls because when I switch from idle to reverse the motor clangs as if you drop a car in gear while revving it. When switching into forward gear most of the time you have to have the high idle lever on the control box idling higher so that the engine wont die when putting it into gear. One last question I have is what is the best way to loosen up the control box and cables so it is easier to shift from all positions. It seems pretty stiff at certain positions. Thanks guys please let me know what the best way to deal with this is.
 

ledzeppelin135

Petty Officer 2nd Class
Joined
Jul 27, 2011
Messages
129
Re: Idle and WOT Confusion

I may also add that my propeller is a 14d aluminum and I am at an altitude of 6500 feet and will mostly be using it at that elevation but a few times a year will be at 2500 feet
 

jgorm

Cadet
Joined
Sep 4, 2011
Messages
14
Re: Idle and WOT Confusion

Its probably a combo of the type of hull, added weight, and the prop pitch. If its not revving up like it does with you alone, the prop may be too big.
 

swordfish25

Petty Officer 2nd Class
Joined
Mar 18, 2009
Messages
117
Re: Idle and WOT Confusion

You may have to replace the controle cables, get these working free and go from there. They make a little click when they go in gear especially if they idle fast. Get the controls free so it can go in gear fast, and not slide in. Like the man said, I think you should try a smaller pitch prop. Rule of thumb, one pitch difference will change the rpms by 300. [ same dia.]
 
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