Timing on 120 hp

maxum_man

Petty Officer 2nd Class
Joined
May 2, 2010
Messages
167
My WOT timing at cranking was set somewhere around 37-38*. I reset it back to 30* per my manual. Would this cause my run to 2500 rpm and thats it problem?

Bryan
 

Frank Acampora

Supreme Mariner
Joined
Jan 19, 2007
Messages
12,004
Re: Timing on 120 hp

That's a definite maybe! Really need to know the year and exactly what you did. Did you synch throttles and timing? Was it really 38 degrees and is it now definitely 30?
 

jerryjerry05

Supreme Mariner
Joined
May 7, 2008
Messages
18,082
Re: Timing on 120 hp

What year and any info will help(fill out the profile).What was it that made you want to adjust the timing?
If all you got was 2500rpm then something else is probably wrong.
Do a compression/spark test.Then tell us what and why you were fixing it.
Ethanol is messing up a lot of motors.It's delaminating the inside of older hoses causing clogs in the carbs and fuel filter.Check for soft hoses and junk in the filter on the motor.J
 

maxum_man

Petty Officer 2nd Class
Joined
May 2, 2010
Messages
167
Re: Timing on 120 hp

Its a 1992 120 hp l drive in a maxum 2100 ldc. I have changed stator, rebuilt fuel pump, and changed fuel hoses. A mechanic here in town said to check timing at cranking speed at WOT. Iy was pretty far off so i adjusted it back to 30* per Clymer manual. Compression was okay at 110,115,115,120. Spark ok too. Im going to go to the water today to test run. I will post later with results.
 

maxum_man

Petty Officer 2nd Class
Joined
May 2, 2010
Messages
167
Re: Timing on 120 hp

ok...took it to the water and ran today. By puting the timing back where it is supposed to be, I lost 500 rpm's. I called a Marine Shop in the next county over and he told me to unhook the yellow wires from the stator to the regulator and try to run it again to see if it fixes the problem. He said he had seen a couple motors that wouldn't run right because they had a bad regulator/rectifier. I don't think this is a fuel problem because it runs smooth at 2000 rpm, it doesn't choke itself out or miss. Imagine if you hooked a truck to a tree with a chain and tried to take off without spinning the tires. Thats kinda what it makes me think of. I have a 13x19 prop on it too. Is this the right prop? 21' Maxum Cuddy Cabin Boat with 120 hp motor.
 
Top