1990-1994 Mercruiser AplhaOne 3.0L Ignition Problems

lthroop

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Hello Everyone.

I have a Mercruiser AplhaOne 3.0L, I do not know the year, but it is between 1990-1994, because I have checked the Serial Number, and I am having some ignition problems. The boat has snow at for about 2 years because when I had it out on the water last, it just died on me while it was running, and I had to be towed back in. I left the country for about 2 years, and now that I'm back, I'm trying to get it running again, and I'm having problems getting spark to my spark plugs.

I have spent the past two weekends trying to figure it out, and every boat shop around where I live does not answer my questions and gives me non-answers about what I could try or where I can get replacement parts. I think my ignition coil is bad, and I've tried looking online for one, but everywhere says they are obsolete and no one can get them anymore. I have a Delco Digital Distributorless Ignition System with a 15071T ignotion coil, and I cannot find a replacement part. If the part is obsolete, shouldn't there be a newer model I could put on there to at least test it and see if the coil is my problem?

I have changed the spark plugs and wires, and unhooked the wiring harness for everything except the essentials for it to just crank up. There was a connector in the harness that looks like the thing you can plug into the back of a Chevrolet for trailer lights, so I unplugged that in case if there was a hidden kill-switch or something like that preventing me from getting it started, so that problem would be mitigated for the time being, and still no spark. I went out at 10:00 at night so it would be fully dark to hold the plug against the block while I was trying to crank it, and didn't see anything happening.

I am at a loss on what to do now. Any help with this would be much appreciated. Please let me know if I need to give more information about part numbers or description of what I've tried so far. I am attaching pictures of the coil and of the ignition system to make sure everyone knows what I'm trying to explain. Thanks again.

Ignition System.jpgIgnition Coil.jpg
 

Don S

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Re: 1990-1994 Mercruiser AplhaOne 3.0L Ignition Problems

What's your serial number, with that (and the proper program) we can get the year for you.
I may be wrong, but I don't think that system has anything to do with Delco, only Mercruiser. Parts are either NLA, or VERY expensive.
Most people just switch over to the Delco EST ignition, parts are easy to come by (It is Delco) and it's used by other Marine manufactures as well. (Volvo, OMC, Marine Power, etc.)
Here is an example of one of the marine kits. 3.0L Delco Voyager EST Marine Electronic Distributor Kit

Cheaper than just one of the parts on the DDIS system.
 

lthroop

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Re: 1990-1994 Mercruiser AplhaOne 3.0L Ignition Problems

The engine Serial Number is 0C871514.

Thanks for the information about switching over the ignition system. I'm checking that out right now.
 

Don S

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Re: 1990-1994 Mercruiser AplhaOne 3.0L Ignition Problems

The engine Serial Number is 0C871514.

Thanks for the information about switching over the ignition system. I'm checking that out right now.

It is a 1990 engine.
 

lthroop

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Re: 1990-1994 Mercruiser AplhaOne 3.0L Ignition Problems

Thanks for looking that up for me. Is there any definitive way I can make sure my coil is bad before I buy that ignition kit or find another ignition coil to replace the one I have if it is bad?
 

lthroop

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Re: 1990-1994 Mercruiser AplhaOne 3.0L Ignition Problems

I've been looking at that replacement Delco distributor, and since I don't have a distributor on there right now because its the DDIS, where would it mount up and will the kit come with everything I need to install it and get spark finally?
 

Don S

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Re: 1990-1994 Mercruiser AplhaOne 3.0L Ignition Problems

You do have a distributor with the DDIS, but it's called a Motor Sensor in the download I posted. it gets replaced by the distributor.
 

lthroop

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Re: 1990-1994 Mercruiser AplhaOne 3.0L Ignition Problems

I tested the coil and the ohm reading is within the specified range. I'm now thinking the amplifier is bad, because I tested to see if I was getting 12V into the amp, and as of now I am not. I connected the Neg to the negative battery terminal and tested the lead, and I got about .02V. Am I testing it wrong, or do the amplifiers go bad before anything else does? I've got continuity in all the wires going into the amp plug coming from the harness.
 

Don S

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Re: 1990-1994 Mercruiser AplhaOne 3.0L Ignition Problems

Am I testing it wrong, or do the amplifiers go bad before anything else does?

Did you test it per the instructions I poster earlier?
 

lthroop

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Re: 1990-1994 Mercruiser AplhaOne 3.0L Ignition Problems

Yes, I followed the directions you sent.
 

lthroop

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Re: 1990-1994 Mercruiser AplhaOne 3.0L Ignition Problems

I went back and followed your directions again, and it appears I have a bad Ignition Amplifier. I have been looking at used amps online and they're super expensive, but that kit you recommended is cheaper, and it seems like it would update the whole system, if I installed that kit, would it eliminate the need for an ignition amplifier, or would I still need one with that kit installed?
 

Don S

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Re: 1990-1994 Mercruiser AplhaOne 3.0L Ignition Problems

It completely replaces the ignition system, all of it.
 
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