78 gulfstream omc won't turn over

jhcon65

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I had my 78 Gulfstream with an omc out drive And ford 302 rated at 190 hp ,on the lake the other day and it ran as usual , brought it home and it sat in the drive way for 3 weeks , went out to start it , all accessories worked , bilge , blower , lights , tilt motor , but when I turn the key to start .... Silence , charged the batteries , tested the starter. Checked the fuses. Nothing . The only thing that is different , is I added an electric choke conversion from the manual .... It's never done this before .... And I can't find any problems any where. ....
 

projo198

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Re: 78 gulfstream omc won't turn over

Did you check the starter solenoid?
 

Maclin

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Re: 78 gulfstream omc won't turn over

Shifter is in neutral, right?

With other items on like lights and blower, when you hit start do the lights dim and blower motor slow down?
 

jhcon65

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Re: 78 gulfstream omc won't turn over

Yes , I bypassed the wiring , and jumped the starter off the battery , and it spun just fine , it didn't start though , but the key wasn't on so the coil wasn't hot , I do have power to the coil with the key on , but still no starter . The lights DO dim a bit when I turn the ignition to the start position . I have the batteries on the charger just to make sure it's not that , and next is to remove the shifter to gain access to the neutral safety switch .. Thank you all in advance for your ideas ,
 

jhcon65

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Re: 78 gulfstream omc won't turn over

Electric shift / neutral safety switch , was the culprit .. I removed it , and used my continuity tester to test the switch . It didn't register at all through the switch , and I realized that the spring inside the switch was not operating properly , it would not allow the arm of the switch to return back from the reverse position , and it was grinding inside the switch as u moved it , something I wouldn't have been able to feel through the selector arm , if I hadn't of removed it . So my reasoning is that the switch was stuck in reverse ' or so the switch thought , so it would not allow the boat to start ... Is that correct ? . Now the next problem , a new switch from my local shop is 400.00$ ?!?!?? And the local boat salvage yard , that did not have one said , if they did have one , their price would be around 200.00$. Is there a better solution ? I looked on Craigslist , and thankfully the guy that was trying to sell broken parts wasn't expecting me to bring my tester , so that one was broken also ... I'm searching eBay ,
 

jhcon65

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Re: 78 gulfstream omc won't turn over

I picked up a whole set up off of eBay for 49.00 , selector arm , cables , electric shift cable , once it arrives I will update , to make sure it was the only reason that the eng won't turn over
 

jhcon65

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Re: 78 gulfstream omc won't turn over

Ok , now I'm confused , got the part plugged it in turned the key .... Nothing
The battery is charged ,I tested that with my dmm , I have 12v at the fuse , but I only have 9.75 v when I test the coil, with the key on the tilt motor switch just makes a single click noise when I try to raise or lower it .... All fuse under the dash are good and don't know of any others none on the engine that I can see ...
 

jhcon65

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Re: 78 gulfstream omc won't turn over

What is this and should it be really hot to touch. ? image.jpg
So this is what I did today ..... Tested the ign switch - have 12v comming in to it . Plus it's a new switch . I have 12v to the electric choke plug , but now only 5.45 v at the pos terminal of the coil itself . I spent a hour under the dash testing all the connections I could see ...... What am I missing , ? would the external resistor cause this ? Or the picture at the back of the motor ? Starting to get frustrated
 

Maclin

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Re: 78 gulfstream omc won't turn over

The thing you are pointing at in the pic is the ballast resistor for the coil. And it will be way too hot to touch once the igniton has been on for more than a few seconds.
 

Maclin

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Re: 78 gulfstream omc won't turn over

Measure the voltage at each terminal on the ballast resistor.
 

Don S

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Re: 78 gulfstream omc won't turn over

If you are having problems with the engine not turning over, then why are you worried about the coil and ignition system. That has nothing to do with the starter cranking the engine.
Now that you put all those new parts in, go back to the troubleshooting guide and go through it again and find out where the power stops again. It's possible you had more than one problem originally, that or your used switch is no good.
 

jhcon65

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Re: 78 gulfstream omc won't turn over

Thanks ... I have read through the guide a few times now ... It's very helpful and as soon as I'm back home I hope to find the prob thanks . I don't believe the switch is bad , I've just been going about this the wrong way , jumping from one potential possibility to the next , instead of the systematic approach , ended up confusing myself in the process ... I think I have a good idea now thanks
 

jhcon65

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Re: 78 gulfstream omc won't turn over

Ok , please forgive me , I'm cutting my teeth on this boat it's my first one ... So I'm starting from square one... I went through the guide step by step . I also removed all the wires to the slave cleaned all contacts , replaced them before starting the testing process .And after jumping the terminals on the slave the engine turns , but still won't fire , with key on . Again with the key in the on position , I tested the voltage at the coil was around 5+v .... i understand that the slave was also the problem , being as I had to jump the terminals , but why the low voltage on the coil and is it normal to have a drop in voltage at the ballst resitor , the voltages are the same on the low side , i have 12 v comming into the resistor , but only 5 + comming out to the distributor
 
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jhcon65

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Re: 78 gulfstream omc won't turn over

ok I did , 12.5 one side 5.6 the other .... the ballast resistor
 
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Boomyal

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Re: 78 gulfstream omc won't turn over

The starter motor turning over (or not) has nothing to do with the ballast resistor. Have you checked all your grounds. including your battery terminals? Does the solenoid click when you hit the key? The starting circuit is pretty simple and straight forward. 12 volts to the ignition switch, 12 volts back to the solenoid and 12 volts out of the solenoid, to the starter. If you have all that and your grounds are good AND the starter is good, it will turn over.
 

jhcon65

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Re: 78 gulfstream omc won't turn over

Thank you , the solenoid does not click when the key is turned , there is no sounds what so ever , I did bypass the ignition switch ,and the slave solenoid, and went straight to the starter and it would crank just fine , but it wouldnt fire , even with the key on . so thats when I tested the coild and found the voltage to be 12.6 comming in but only around 5 + out , the only test i have not been able to do , simply due the fact I have no "helper " is to test the slave while someone turns the key to the start position ..... and to add to the confusion , the out drive only clicks when I try to raise it , it makes a single click when I attempt to raise it . ......
 

jhcon65

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Re: 78 gulfstream omc won't turn over

I ran a jumper wire from the batt to the coil and then another from the hot side of the slave solenoid to the terminal on the slave , and it fired . Sooo I'm guessing my slave was bad too , AND the tilt motor only clicks when the switch is activated so ill pull that to test as well
 

Boomyal

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Re: 78 gulfstream omc won't turn over

I ran a jumper wire from the batt to the coil and then another from the hot side of the slave solenoid to the terminal on the slave , and it fired . Sooo I'm guessing my slave was bad too , AND the tilt motor only clicks when the switch is activated so ill pull that to test as well

I would disconnect your tilt motor and apply 12 volts directly to it. That will tell you if it is the solenoid or the motor itself.
 

jhcon65

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Re: 78 gulfstream omc won't turn over

OK , I did what you suggested , i disconnected the tilt motor and jumped it straight to the battery , it would raise only about 3-4 inches then bog down and stop , I tied a rope to the out drive and was ale to bringt it all the way up while jumping the motor via the solenoid ....im sure that was a sight , tied the rope around the outdrive , and then leaned way over the back of the boat , with one hand on the jumper wire , and the othe holding the rope around my waist , and leaned back while jumping the solenoid .....at least it worked , the outdrive came all the way up .from what Ive read on here it could either be the motor itself , or the clutch pack . I will check the commutator and motor today ... and replace the slave this week , and see where im at after that
 
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