1972 Mercury 115 horsepower with little power

L

lokai 1972

Recruit
Joined
Sep 19, 2010
Messages
1
Hi, I have a 1972 6 cyl. 115 horsepower on a 18 ft Tri-hul.
I had the carbs cleaned, the comp. is good and even. It starts good,
But the throttle moves to far before I get much power. Also it seems not to have enough power at the top end. I also believe that It`s using to much gas
for the speed I`m getting. I also put new plugs in. The shifter puts it in gear right away but then it stays almost at idle until you move the throttle 3/4 of the way forward. Can the timing advance be off?
 
75TowerOfPower

75TowerOfPower

Petty Officer 1st Class
Joined
Apr 17, 2009
Messages
331
Re: 1972 Mercury 115 horsepower with little power

Timing might be fine. There are two cables that run from the Control to the motor, one for drive selection and one for throttle position. Take the cowl off and have someone move the throttle or move it and go look at it. This happened to me once where I broek the clip holding the cable to the throttle therefor not actually moving the throttle.
 
SeaKaye12

SeaKaye12

Lieutenant Junior Grade
Joined
Jul 3, 2005
Messages
1,116
Re: 1972 Mercury 115 horsepower with little power

With the cowling off you can see the chain of events...as you advance the throttle most of what happens at first is spark advance...but as the lever is pushed all the way you should then see the carbs throttle plates opening fully and in harmony with each other.

Do this with the engine shut off and you should be able to see what's wrong.

Chuck
 
M

Moody Blue

Captain
Joined
May 24, 2004
Messages
3,136
Re: 1972 Mercury 115 horsepower with little power

The action you describe with the controller (MerControl) sounds about right. Not much throttle until 3/4 travel or more.

My '71 Merc 800 behaves the same way. Not until I have the throttle lever at about the 10 o'clock position do I see much increase in RPM. My WOT position is about the 8 o'clock position, down past horizontal.

As for using too much gas, we're all of the same mind :D. They all use too much gas. As a general rule of thumb, your motor should consume about 12 gallons of gas per hour at WOT. Of course throttling back will give better economy.
 
You must log in or register to reply here.
Top