Merc 1500 needs LOTS of electricity to start

[ZmOz]

I have a '74 Merc 1500. It runs great, but starting cold is extremely hard. I have narrowed it down to an electrical problem. I though the battery was bad, so I took the new battery out of my truck and tried it in the boat, still didn't get enough power. I then hooked up one of those portable jump start things - started right up. Why the heck does this thing need so much power? I'm thinking it might work if I get a nice expensive optima battery...but I shouldn't NEED that. I can't imagine the batteries in the '70s being able to give that much power. Should it really be using this much power?

 

[NEECAPRS]

Re: Merc 1500 needs LOTS of electricity to start

Take a look inside the starter. If you clean up the commutator and, especially, just lube the bearings with light oil you may get a whole new motor! Hope it's that simple-- it was on my 1965 1000. Good Luck!

 

[snapperbait]

Re: Merc 1500 needs LOTS of electricity to start

Good battery cables are a must... Don't overlook them... Even if they look good on the outside they may be corroded on the inside..

 

[The Marine Doctor]

Re: Merc 1500 needs LOTS of electricity to start

Chokes closing?<br /><br />Might be that primary compression is low...older engine. <----suction.<br /><br />Try a decarb.<br /><br />TMD