Volvo Penta 2002 ? Blown a Fuse, Now Non Start

janul15

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Feb 15, 2020
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Happy New Year all. Done something silly. My alternator has not been working for a while, I've been charging the batteries via a solar panel, enough to start the engine. Decided to take out the alternator today to fix/replace it. I didn't disconnect the batteries. I moved the alt. a bit, it must have touched (and shorted) something, The engine tried to start for a second or 2, and got quite a big spark and smoke (where the alt. was touching something) No fire followed. Now I turn the ignition switch, and nothing happens; no sound, no attempt to start . Have I blown a fuse ? If so where does a replacement go? Or could it be more serious?
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
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Follow the electrical schematic for your specific motor that you did not list. Start testing from the battery and work your way to the helm.

Could be the big circuit breaker, could be dead relays, could be a blown diode, could be a fried wire.

However since there are about 15 different 2002 VP motors, we would be guessing on where to start and what you shorted

Generic information.

Start at battery, you should get battery voltage at every connection to the starter B terminal, to the main circuit breaker, the alternator fees, and the red wire running to the helm

After the key switch, you should have battery voltage on the purple wire (ignition) behind the helm, at every gauge, at the alternator excite wire, the coil positive, and various model specific ignition bits
 

cptbill

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Check your wires down at the starter, one of then is a fusible link it probably burned up. Gentle pull on the wire and it will stretch if it's not burned through all the way
 

janul15

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Feb 15, 2020
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71
Hi Scott, I realise I may not have given you enough info, but I also may have confused you. The engine is Vovo Penta 2002 series (not the year 2002). It's an 18hp diesel. That may narrow things down a bit.
 

alldodge

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Being a diesel I moved it to the diesel section

The drawing online I'm finding doesn't show a fuse but do look close. Next use a voltmeter and trace voltage from Bat to key and back to motor
 

janul15

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Feb 15, 2020
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Hello, thanks for your replies. Had a look at things today, and moved the alternator out the way. (disconnected the battery this time) The fuse box (I think that's number 2 on the wiring diagram) looks O.K. I'll send a picture of some burnt out wiring from the solenoid/starter assembly. The red/yellow wire may be O.K.. The next one to it (should be red) is completely burnt through. I must replace that one, but I can't see how to attach this at a point under my fuse box, which is the white (overexposed )square on my attached photo. I think that's going to a relay, under the fusebox, which seems inaccessible. Any ideas on that? While I'm tackling that, I've bought a push button starter switch, so I can crank the engine, bypassing some of the normal electrics.
 

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alldodge

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Diesel wiring in most cases is fairly simple, the issue I have with VP is their wiring diagrams are terrible.

Being unable to get to something is what all mechanics run into. Just need to figure out what needs to be removed to gain access. Some things come all the way to remove the motor

Need to ohm out all circuits to find out which ones are shorted. Most times after something like you had it can wipe out the alternator and control boards
 

QBhoy

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Hi. Yeah. You’re going to need to rewire that for sure. Test the starter and alternator too. Battery might be compromised as well.
If it helps you any…if she’s like most of the small VP diesels I’ve been in about, there will be at least one, if not two relays inside that electrical box. The box that the main harness loom goes into. They will need testing. You can buy that whole electrical box fairly cheap if need be.
 

janul15

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Feb 15, 2020
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I'll update you all. I've removed the alternator. I had fitted an emergency bypass switch to start the engine, and it worked. I just wanted to upgrade that switch, and my cables came off the solenoid/starter combination. Where should my 2 wires from this starter switch attach to the solenoid/starter motor combination?
 

alldodge

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If I understand you correctly
You have a remote start switch and want to know how to connect it so it can be used. If correct post pic of starter?
 

janul15

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Feb 15, 2020
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Hello alldodge. Yes, you're right. I should be able to do this from previous information, but I want confirmation. There is a picture on one of my posts above (Jan 2 2024). This shows a burnt out red wire on a solenoid post, and a red/yellow wire on another solenoid post. Are these the two posts that I attach the replacement starter switch to? My thought is that they are.
 
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