1979 90hp Merc won't crank.

[muskiemike12]

I have this vintage motor. Just took the boat out of storage on Saturday at 10:30 am. It took about 3 to 4 minutes for the motor to start the first time. Did I fry the starter doing this? It started fine the rest of the day until 6:30 that evening. I turned the key and nothing. I then held the key turned for about 10 seconds and I could hear a clicking coming from the motor. It finally turned over once and fired. Back to the dock I headed. It will not turnover any more. I checked the starter solenoid and that is good. Do I need a new starter? Is there any other part that could be bad? The connections are tight and clean. The battery is a year old and has a full charge.

Thanks!

 

[nccatfisher]

Brushes are probably fried. It would be much cheaper to repair that starter if you know how of have a facility close than to replace it.

 

[user 6672]

Did it make a clicking sound when key turned? or did the bendex engage and not have the power to turn over the motor?

If the bendex engaged and it didnt have the power more than likely as said above brushes and mag's. Doing a rebuild is as easy as it gets and its cheap.

If it clicks and no bendex movement it is your solenoid or poor connections..

 

[muskiemike12]

The bendex did not engage when the key was turned. There was an intermittent clicking at first, now it doesn't click at all. All the connections are tight and I replaced the solenoid and that made no difference. I would hate to have to pull it out of the lake because we don't have a trailer and the guy up here who works on the older motors is 40 minutes away. Hoping it is some thing I can fix on the water. I see that iboats has the repair kits but I don't know which one I would need. There are 5 different kits. The complete kit that includes everything is only $70 less than a new starter. When the motor was starting the first few cranks on the starter were always slow. Once it got turned over a few times it cranked just fine.

 

[user 6672]

The starter is held on by 4 bolts and the positive wire. if you are going to rebuild it you dont have to pull the whole boat out.

Connections are tight and clean? no green buildup or corrosion on any of them?

If it does nothing now there is 1 inline fuse connected to the solenoid via a red wire (i think)...

for trouble shooting.. I would take a multimeter and test at the solenoid for 12 volts while turning the key, after that check for 12 volts at the pos/neg on the starter with key turned. If you don't have 12 v at the starter with key turned it is either your solenoid or your control box or previously mentioned fuse..


I am only a shade tree mechanic and I am only giving suggestions..

 

[muskiemike12]

Thanks Canoeman, Ill give that a shot.

 

[muskiemike12]

Everything tested fine with getting full voltage to the starter. All connections were checked twice and no issues there. After the 12 bolts holding on the upper motor shroud were removed I took the 4 bolts off holding the starter. Going to get it tested. What rebuild kit would I need to fix it?

 

[user 6672]

you can always bench test the starter yourself.. Take jumper cables and hook up pos from bat to pos of starter and neg of bat to neg of starter.. if its good it will kick a bit so you or someone may want to hold it on a bench or a soft jaw vice.

If the bendex doesnt kick out you may need to go through it and clean it out and put new brushes on it.

I think the set you want is # 7 on this diagram.

75384 BRUSH SET

And here are 2 rebuild videos for your starter..

https://www.youtube.com/watch?v=1N4GZTHCB-0

https://www.youtube.com/watch?v=MQf5UB59VJc

 

[muskiemike12]

The first thing we did was jump it on the motor and it cranked right over. Checked all the connections to make sure we were getting the proper voltage and everything checked out. Still won't crank with the key. Jumped it again and this time it turned very slow.

 

[sawmill]

Did you clean your battery terminals? If you did I would have your battery load checked as sometimes you can have 1 or 2 bad cells and it would still show 12 volts but not have the amps to crank the engine over. Just a thought.

 

[muskiemike12]

Battery is clean and tested at 12.6 volts. The first time I started it this season it cranked the motor for 4 minutes with no problem. Its hooked up with my onboard charger, so it has a full charge.

 

[sawmill]

As I said you can have it test 12.6 volts and be fully charged but if a cell is bad it won't crank the engine. I learned this the hard way. You can have it tested any where that works on motors. I once had a new on that was bad and had to be replaced the second day I owned it

 

[JMichael]

I'm gonna go with sawmill on this one. Evey time I've seen a motor click like a terrorist bomb, it was due to a bad solenoid or low amp/volts. And 12.6 is not necessarily good since a new battery will read 13+ but you need to be concerned with the amps also. So load testing should be your next step. And just because the battery worked good yesterday doesn't mean it's good today. My motorcycle has been starting and running great this year. Last week I went out to take it for a ride and it would barely make the starter grunt. The Battery Tender Jr shows it to be fully charged (green light) and it won't even turn it over. New battery should be here today.

 

[muskiemike12]

So a battery that worked just fine in the morning can go bad by that afternoon?

 

[sawmill]

muskiemike12 » Today, 09:13[/url]"]So a battery that worked just fine in the morning can go bad by that afternoon?

Yes and it does not mater how old the battery is. Some of the new batteries are junk. As an example the battery in my quad I have on a battery tender and I have to replace it every year at 90.00 a pop. Not no more I changed the battery box and put a different one in it.

 

[muskiemike12]

I just had the starter tested at a local marine shop and it turns out that it was the 34 year old starter that was the culprit. I just ordered a new Arco starter off iboats and will be at my door tomorrow. While pulling the starter out I noticed that the cable to the choke solenoid was in rough shape. After these 2 fixes I hope it will run the rest of the year smoothly.

 

[user 6672]

muskiemike12 » Today, 11:28[/url]"]I just had the starter tested at a local marine shop and it turns out that it was the 34 year old starter that was the culprit. I just ordered a new Arco starter off iboats and will be at my door tomorrow. While pulling the starter out I noticed that the cable to the choke solenoid was in rough shape. After these 2 fixes I hope it will run the rest of the year smoothly.

Hopefully with those 2 fixes she spins right up..

let us know..