Wont Start

[Cap Erict3]

Do you have 4D or bigger batteries? Do you have a Perko switch and 2 batteries? Have you tried the "Both" battery selection?

[cortezsailor]

yes no difference wether I use all batteries or only start battery. I have 2 Gel Cell house , each at 255 Amps and a new starter battery . I will be doing a lot of testing of wires over the next week or so, thanks for all the help its been great

[Badsanta]

I had similar experience and found that I had a battery with internal shorts and it would pull down the voltage of the others. I only had a large house bank with no separate start battery. I finely pulled all the batteries and had each tested. Once I found the bad one and replaced it, all worked well. I dealt with this for months and only when I disconnected the batteries and charged and load tested each separately could I find it.

[kriach]

Check the large battery cable to the starter for internal corrosion. I have seen this same situation occur in cars and that was the cause. If the heavy cable has internal corrosion it will not matter how big a battery you connect, it still won't turn over.

[Lodesman]

Casting about CF, found a wiring diagram for the Perkins: http://www.cruisersforum.com/forums/...am-107801.html

Some Delco starters have a built-in thermal breaker; if you are using a starter that has this IOCP, then perhaps you should try bypassing it if possible, or consider getting a non-OCP starter instead.

[Cap Erict3]

Originally Posted by cortezsailor

yes no difference wether I use all batteries or only start battery. I have 2 Gel Cell house , each at 255 Amps and a new starter battery . I will be doing a lot of testing of wires over the next week or so, thanks for all the help its been great

The trouble with intermittent issues is the same as with the watched pot.

It will be easier to test if one person operates the switch while another chases the voltage. Connect volt meter to "-" battery terminal and "+" terminal. Expect 12 volts minimum.

When you try to start, keep switch in start position and move "+" meter lead from battery to first large solenoid terminal (wire check) then second large solenoid terminal (solenoid check) then starter terminal. Voltage should be very close to battery voltage under load. 10.5 volts minimum.

With starter switch still engaged move "+" meter lead to engine block. (- wire check) Expect "0" volts.


Loose connections at the first solenoid terminal are common.

After doing these checks the starter should be very warm.

A bad ignition switch is a possibility.

[cortezsailor]

Bonus , thanks Lodesman


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[cortezsailor]

Thanks Captain will test


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[damir s]

Maybe pinion gear does not go well in the flywheel try to turn a little flywheel.

[undercutter]

After looking at the wiring diagram from an earlier post I do not see anything other than the neutral safety relay between the ignition switch and the starter.

The first thing I would check would be the voltage at the ignition wire on the starter solenoid while you are engaging the starter. If there was a problem with the neutral relay itself (not the switch) then you would have to bypass this by connecting the ignition wire from the switch directly to the starter.

Or just try replacing the relay as these are fairly common and cheap.

Although the wiring diagram from the earlier post is not complete (doesn't show shut down solenoid nor wiring for same) it looks fairly basic. In the end I am sure it will be something stupid or simple.

[Cap Erict3]

Originally Posted by cortezsailor

Thanks Captain will test


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Just Cap.

[a64pilot]

Try this,
When it won't start, try the screwdriver across the solenoid trick, that bypasses everything except the battery, wire and starter, if the screwdriver trick works, then it's in the low current starting side, if it does not work, then your problem is in the big wire, high current side.
My bet is a high resistance termination on one of your wires, that when hot loosens up even more and won't work until cool again.

[undercutter]

Originally Posted by a64pilot

Try this,
When it won't start, try the screwdriver across the solenoid trick, that bypasses everything except the battery, wire and starter, if the screwdriver trick works, then it's in the low current starting side, if it does not work, then your problem is in the big wire, high current side.
My bet is a high resistance termination on one of your wires, that when hot loosens up even more and won't work until cool again.

The hypothesis is perfect but the methodology is faulty.

Kidding but really though, wouldn't it be better to run a second lead wire from the ignition terminal of the solenoid long enough to reach the battery? This way a test could be performed under conditions where the engine has been run up to operating temperature and shut down with a subsequent restart attempted. If the engine will start by powering the solenoid directly from the battery then the problem is on the signal side. If it won't start, the problem is in the power supply or ground from/to the battery. The ground side is more critical than people think and I have seen many examples of a bad ground resulting in this exact problem.

Also, not having to crawl around in the bilge around potentially dangerous or hot objects while trying to start the engine with a screwdriver must be better.
Besides you avoid all those nasty sparks and damaged terminal posts.

[Winf]

This may be a long shot but don't forget to check your battery isolator switch if you have one.

Had trouble with mine just today when we were lifted into the water after haul out. Had to bypass the isolator temporarily to get going and clear the slip. Must be a dodgy contact in the isolator somewhere.

Getting power to the starter circuit was intermittent and it was only dumb luck that when I turned off the isolator, just my hand touching the lever was enough to make the starting warning buzzers go off so I thought that was the probable source of the trouble.

Winf

[Cheechako]

I like the shorted battery idea. I have had that happen 2 times with fairly recent batteries. So the OP leave the dock where the charger has been on, motors out, goes sailing and then the engine wont start.... It was easy to find the shorted battery on mine. After charging at the dock all night I felt the batteries. One was very warm, the rest were not.