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jasper aus
08-13-2013, 08:43 AM
Hi, after a bit of a hand diagnosing a problem with my stars and stripes. Not many early girls over hear in Australia so would REALLY appreciate some help so I can sort it for the start of the season.

I can usually get it to start on the trailer before i take it to the boat ramp and it will usually start at the ramp but if it stalls backing it off the trailer (or once i turn it off after it has been in gear) it will often not start again. Everything works, gauges light up, stereo etc but when you go to start there is nothing.

To me it seems like it doesnt know that its been taken out of gear. Sometimes it will start after a fiddle with the key or with the shifter (not sure if that actually does anything) but other times I've had to paddle home.

Any ideas?

Oh and its an 85 SS 351 with the powerslot.

Thank heaps!

thatsmrmastercraft
08-13-2013, 10:41 AM
Welcome to Team Talk. We should be able to assist in getting your classic running like it's new. First some questions to clarify:
When it won't start, will the engine turn over with the starter motor and not fire, or not turn over at all?
Does you boat still have points or has it been changed to electronic ignition?
How long since the spark plugs, distributor cap & rotor have been changed?

jasper aus
08-14-2013, 07:33 AM
Thanks for the reply. This is a pic of it. Its standard as I am aware (apart from bimini and high pole so I would doubt it been converted in any way. It only has a few hundred hours on it and I have serviced it regularly.

When I mean it doesnt start i mean there is nothing when the key turns. No cranking, its as though it has a very flat battery except you can still hear the hour meter ticking and all gauges still work. It doesnt happen all the time and always happens after it has been dropped into gear and then the engine stopped and started again. It doesnt seem to make a difference if it was placed into neutral before stopping or just left in gear, then moved to neutral to restart.

I'm not very familiar with these yet but i imagine there would be some sort of solenoid/ inhibitor switch to prevent starting in gear. Is it likely to be something like this?

Once again its a 351 PCM with the powerslot.

thatsmrmastercraft
08-14-2013, 10:06 AM
Should be simple enough to diagnose this as it within the start circuit, so we are dealing with:
Battery
Battery cables
Solenoid
Ignition key
Associated wiring

I would bet on a bad battery connection, so the first thing I would do is remove and clean all battery cable connections. Both at the battery, both at the solenoid, at the starter, and especially the ground at the block. Use a stainless steel brush for cleaning connections as this does a much better job than a plain steel brush.

You could have a bad ignition switch. I replaced mine last year for a similar problem.

A guy can also have problems from bad connections at wiring harness connectors. It would be worth your while to disconnect each large connector and inspect for corrosion. Apply a little dielectric grease before re-connecting. Use a little dielectric grease at all your electrical connections, including the battery, as this will help fight corrosion.

liledgy
08-14-2013, 01:55 PM
Take a jumper cable from battery to the solenoid and see if it turns over. If it does you know one of the connections on either end of the cable is bad or your cable is shot

MikeyOrange88
08-14-2013, 10:45 PM
Sounds like the symptoms of a neutral safety switch that is slightly out of adjustment.
I used to have to shift back to reverse, then neutral to get it to start, very intermittent. Scares the heck out of you though.
The adjustment is on the cable where it attaches to the transmission, barrel bolt. Just a revolution or two is all it may need.

thatsmrmastercraft
08-15-2013, 12:52 AM
Sounds like the symptoms of a neutral safety switch that is slightly out of adjustment.
I used to have to shift back to reverse, then neutral to get it to start, very intermittent. Scares the heck out of you though.
The adjustment is on the cable where it attaches to the transmission, barrel bolt. Just a revolution or two is all it may need.

Hadn't thought of that. You may be correct.

MikeyOrange88
08-15-2013, 11:00 AM
It could be the switch is going bad also. It could be jumped out to test that theory.
It is the two white wires that connect to the switch on top of the transmission (at least on mine).