Wrong Manual

scatgo

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I have a Mer Cruiser #17 manual that is useless to me at the moment. I have a 1987 Searay with a 350 votex engine. Right now it wont turn over due to electrical issues. All of the wiring diagrams in the manual are for 93 and up EFI Engines. Is there a Merc manual that would better serve my needs? The engine has what looks like a Thunder Bolt ignition system. Would the original set up in 87 have a thunder bolt system? I was expecting to see a points ignition system on a engine that old.
 

Fun Times

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I have a Mer Cruiser #17 manual that is useless to me at the moment. I have a 1987 Searay with a 350 votex engine. Right now it wont turn over due to electrical issues. All of the wiring diagrams in the manual are for 93 and up EFI Engines. Is there a Merc manual that would better serve my needs? The engine has what looks like a Thunder Bolt ignition system. Would the original set up in 87 have a thunder bolt system? I was expecting to see a points ignition system on a engine that old.
What year is the engine? Is there a serial number? Photos may help here too.

https://www.scribd.com/document/385929465/2008-Mercruiser-service-manual-index-pdf#
 

dubs283

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Would the original set up in 87 have a thunder bolt system? I was expecting to see a points ignition system on a engine that old.
Yes.

Mercruiser started thunderbolt styled electronic ignition on inboards around 1983. It quickly migrated to MCM (sterndrive) and was ubiquitous through the mid 1980s through the 1990s and beyond.

Still seen today on older packages parts are readily available (save for new oem ignition modules) nationwide along with literature for troubleshooting and repair.

FYI the copy of manual #17 I have includes sections for carbureted engines including mercarb, quadrajet, and webber along with proper wiring diagrams.

Serial number ranges for said manual include for the 5.7 (350 cid) engine w/o efi as 0D830700 - 0F601957
 

scatgo

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What I can really use right now is a wiring diagram for my engine. I am getting no power to my starter. Cant seem to find one online.
 

Fun Times

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What I can really use right now is a wiring diagram for my engine. I am getting no power to my starter. Cant seem to find one online.
To the starter or from the starter on up to the engine when tested with either a multi meter or test light?

Some models has either a 50 or 90 amp fuse connected to the main starter post which protects the engine components.

Do you see a block type fuse device connected to the battery cable and other wires connected too.
An example,
1682286498318.jpeg
 

Scott Danforth

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I have a Mer Cruiser #17 manual that is useless to me at the moment. I have a 1987 Searay with a 350 votex engine. Right now it wont turn over due to electrical issues. All of the wiring diagrams in the manual are for 93 and up EFI Engines. Is there a Merc manual that would better serve my needs? The engine has what looks like a Thunder Bolt ignition system. Would the original set up in 87 have a thunder bolt system? I was expecting to see a points ignition system on a engine that old.
if you have a vortec headed engine, the engine (or at least the heads) are 1996 and newer.

in 1987 only the 4-cylinders still had points.

What I can really use right now is a wiring diagram for my engine. I am getting no power to my starter. Cant seem to find one online.
you will never find a factory manual online. that is a breach of copyright laws. you can get them new from http://publications.brunswick.com/

big cable to the B terminal on the starter should be direct to the battery. make sure you start at the battery and clean every terminal and connection to the engine block and then work your way to the helm. if the cables are crunchy or green under the insulation. replace them

your starter gets power to the S terminal from the starter slave relay. that is the yellow wire with the red stripe.
 

scatgo

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I had a little time to look into this after work today. I unplugged the 10 pin harness then ran a jumper from the + post on the battery to the yellow terminal on the slave relay and got nothing. When I plugged the 10 pin plug back and did the same the engine turned over nice and strong. Correct me if iam wrong but wouldn't this suggest the problem is at the main battery switch or from the battery switch up to the dash?
 

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nola mike

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I had a little time to look into this after work today. I unplugged the 10 pin harness then ran a jumper from the + post on the battery to the yellow terminal on the slave relay and got nothing. When I plugged the 10 pin plug back and did the same the engine turned over nice and strong. Correct me if iam wrong but wouldn't this suggest the problem is at the main battery switch or from the battery switch up to the dash?
Direct connection between the battery and yellow/red on the slave should turn it over. Impossible for it to turn over via the ignition but not a jumper.
 

scatgo

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Idk. What you described can't happen, so can't suggest much.
Cant happen? Will turn over when jumped from battery to slave. Wont start with ignition switch. Take a look at the wiring diagram i posted.
 

nola mike

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Maybe I misunderstood what you said:
" I unplugged the 10 pin harness then ran a jumper from the + post on the battery to the yellow terminal on the slave relay and got nothing. When I plugged the 10 pin plug back and did the same the engine turned over"

2 y/r wires on the slave. If you apply 12v to the smaller wire and it turns over, that means your slave is good. So you're not getting 12v from the helm. Likely suspects would be connections at the ignition switch, neutral safety switch, and cannon plug. So disconnect the wire at the slave and with the key in start position check for voltage at each of those points.
 

scatgo

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Maybe I misunderstood what you said:
" I unplugged the 10 pin harness then ran a jumper from the + post on the battery to the yellow terminal on the slave relay and got nothing. When I plugged the 10 pin plug back and did the same the engine turned over"

2 y/r wires on the slave. If you apply 12v to the smaller wire and it turns over, that means your slave is good. So you're not getting 12v from the helm. Likely suspects would be connections at the ignition switch, neutral safety switch, and cannon plug. So disconnect the wire at the slave and with the key in start position check for voltage at each of those points.
Thanks for the help. But iam not sure what a cannon plug is. And where would the neutral safety switch be? Is that the button on the shifter? Is that the interrupter switch?
 
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