90 inline turns over slowly.

[Black Max]

Just pulled this 1974 engine out of storage to revive it our the past few weeks. I came to crank it yesterday and with a brand new battery the motor only turns over slowly. Is this a problem with the starter possibly. A week ago I had the plugs out and it turned over rapidly like normal. But with the load of the engine trying to crank it slowed down dramatically. I did actually actually get it cranked up and it purs like a kitten, I just have to get this starter problem fixed (possibly) then put it on the water for its maden voyage. 90hp inline +1976 15ft hydra-sport hydra-flight= danger. Thanks, Zane

 

[Laddies]

Re: 90 inline turns over slowly.

Has the engine been prelube? Is the battery of good capacity and a strating battery not a deep cycle? If both the other quistions are yes and the connections are good, then you probably need a starter repair

 

[Black Max]

Re: 90 inline turns over slowly.

Yeah the motor has been lube up pretty good with some chesterton penetrating fluid and distributor greased. I have a starting battery, but what actualy is the difference betweeen a deep cycle (which all say trolling/accessory battery) and a starting battery. In the past I had a deep cycle battery which actually said it had more cranking amps than my starting battery. I will try and crank her over again today with a little extra lube. Can't hurt.

 

[AMD Rules]

Re: 90 inline turns over slowly.

The inlines are notorious for wanting every last bit of juice from the battery source. Double check all connections and wires between the starter & the battery. A loose/poor connection, or corroded wire(s) can contribute to hard starting under load.

 

[phatmanmike]

Re: 90 inline turns over slowly.

MAKE 100% sure that your batt cables have GOOD CLEAN STRONG connections, make sure they are large enough to handle the required ampacity, and make sure that they are not rotten and deteriorated.<br /><br />the older merc batt cables are built into the control cables main wire harnes, and merc was famous for using crappy sheathing on their wires

 

[rodbolt]

Re: 90 inline turns over slowly.

but a 5 minute test session with a voltmeter and doing a voltage drop test on the cables can find about anything ya need to know

 

[Black Max]

Re: 90 inline turns over slowly.

I rebuilt my merc control from scratch with all new wires. I think I may have gotten to ancy and disregarded cleaning my connections. I recall that the battery terminal clamps were hot after trying to start him up. I believe I was getting ahead of myself. I just finished putting in some new needle and seats, so I will try and crank it up in a few minutes.(fingers crossed) Rodbolt-I have the volt meter, just test the pre-volt and monitor the drop in voltage while cranking? Thanks for all the help guys, I would like to get out for a test ride before this weekend goes buy, I've been down for months. (R.I.P 85hp Merc 6-7-05)

 

[rodbolt]

Re: 90 inline turns over slowly.

its not a battery voltage drop test but that needs to be done first. what you measure next is the drop[ across the connection points.<br /> I will try to scan a page out of a training manual with a diagram if I can figgure out how to post it

 

[Black Max]

Re: 90 inline turns over slowly.

Here is what I did, Connected opposite ends of jumper cables from my negative battery terminal to my engine ground. In doing this I have realized that there is true spark between my engine ground, which I assume is causing me to loose some power. I cleaned up the grounds, now I have it turning over a much faster, but still once she wants to crank she barely turns over, but still runs. I also tested my battey voltage, when turning my volts drop to around 10.5 which is pretty decent. On top of all that the starter let out a little smoke from the bottom where the brushes are probably at, after some constant cranking. I just can't catch a break. If it isn't one thing it's another. Might have to start digging through my goody boxes in search of another old starter. (R.I.P 85hp Merc 6-7-05)

 

[Black Max]

Re: 90 inline turns over slowly.

 

[jfarmer]

Re: 90 inline turns over slowly.

I had a similar problem starting a '78 50hp. I pulled the starter apart and found water and filings filling the bottom of ther starter around the brushes. I replaced the brushes and gave it a good cleaning. Even though the armature looked a little cooked it starts like a champ now. <br />I also replaced the battery cable leads in the harness that were cracked and coroded.<br /><br />Hope this helps.