voltage drop 1991 200hp johnson

JESSIELSMALL

Petty Officer 2nd Class
Joined
Mar 15, 2006
Messages
112
when i connect my volt meter to the battery , it reads 12.2 volts. i leave them connected and turn the key and the voltage drops to 11.5 is this normal or will it cause my engine not to fire
 

F_R

Supreme Mariner
Joined
Jul 7, 2006
Messages
28,195
Re: voltage drop 1991 200hp johnson

When you say you turn the key, do you mean just turn it on or do you mean turn it to run the starter?

The voltage change means something is drawing a heavy current (like a starter motor). Or, if nothing is drawing a heavy current it means the battery is shot or discharged. I strongly lean towards the first explanation....which actually is a good reading for cranking voltage.
 

JB

Honorary Moderator Emeritus
Joined
Mar 25, 2001
Messages
45,907
Re: voltage drop 1991 200hp johnson

I agree with F_R.

If you give us the big picture maybe we can help.
 

JESSIELSMALL

Petty Officer 2nd Class
Joined
Mar 15, 2006
Messages
112
Re: voltage drop 1991 200hp johnson

I agree with F_R.

If you give us the big picture maybe we can help.

it drops when i turn the key to engage the starter. im trying to figure out why it will not start, it will run great after i get it started, but let it sit for a couple of days and all it will do is turn but not start.
 

F_R

Supreme Mariner
Joined
Jul 7, 2006
Messages
28,195
Re: voltage drop 1991 200hp johnson

Check for spark while it is turning but not starting. Check with all the plugs in. If it has spark, make sure your starting procedure is correct. It's amazing how many people don't know how to start their motor because nobody ever told them and they never read the owner's manual.
 

HighTrim

Supreme Mariner
Joined
Jun 21, 2007
Messages
10,486
Re: voltage drop 1991 200hp johnson

Look for the sticky at the top of this forum on starting procedures written by IWOmbat, it should lead you in the right path.
 
Top