H.E.L.P crusader wont run and i have tried everything

Greetings, I have a crusader 350 with GM block, 270HP, regular carb, no computers to deal with its a 1988. The engine catches when the key is turned and the starter kicks in as normal, however as soon as I let go of the key the engine cuts off. If I pump the key to keep the starter engaged the engine keeps running...obviously I only did this to test..

So I started to check and replace things. So far I replaced the ignitor in the distributor, new dist cap, new rotor, added ballast resistor thinking its a coil issue, even replaced the coil. Also checked fuel pump and also put on a new carburetor . Still starts then cuts off.

Any suggestions?

Classic problem. Your ballast resistor circuit is not working properly. Turn the ignition ON and see what voltage is at the + coil terminal. Should be at least 8 volts.

Jeff

Thank you Jeff, I will try that today..

novenogan said:

Thank you Jeff, I will try that today..

Click to expand...

My chrysler 440 did that. It was a purple wire with a yellow tracer that had come unclipped from the ballast resistor.

Added new ballast resistor, still not helping, again starts runs for a few seconds then shuts off. Not a fuel issue, tested that. Someone said that an oil pressure sensor can shut off engine is that correct?

I would focus on what Jeff said. Ballast resistor circuit. I had a similar issue years ago with my 318's and found my ignition switch was bad. Turn your key on and check voltage at the coil+. If it's good try it again but joggle the ignition switch and make sure it remains constant.

Russ

You very likely have an ignition circuit failure.

The reason why it starts during starter motor action, is due to the "start-by-pass" circuit. This circuit momentarily by-passes the balast resistor, and supplies full voltage during the Lowered Voltage caused by the starter motor amp draw.

When you let up on the key switch..... the by-pass becomes inactive....... thus relying on the standard ignition circuit via the balast or reduced coil voltage.

Find out why the ignition circuit is not providing the correct voltage to the ignition coil, and you will have found the problem.

Use the good 'ole P of E (process of elimination)
One item, and one item ONLY at a time.

When used systematically and methodically.... it won't let you down!

.

..."Turn the ignition ON and see what voltage is at the + coil terminal. Should be at least 8 volts."

Have you tried this yet?

Jeff

Hi and thank you, yes I actually even ran a jumper from the +battery, to the + side of the coil to bypass the ignition switch, at one point. Also when key is on the "on" position, I have 8V at the coil. This issue is really difficult t resolve. Today, taking suggestions I also bypassed the oil pressure sender to see if it was the problem. It wasn't. Ugh!! Anymore ideas?

Have you tried disconnecting the tachometer wire?

Let's re-visit this.

novenogan said:

Greetings, I have a crusader 350 with GM block, 270HP, regular carb, no computers to deal with its a 1988.
That pretty much eliminates an EFI electric fuel pump, and the related safety features.
IOW, a No-Start due to no EFI fuel pressure due to a faulty N/O low oil pressure switch, or a faulty relay.

A carburetor style electric fuel pump.... when not continuously powered.... should not cause a no run.
The carburetor is more than capable of holding enough fuel to fire up on, even if the pump was being operated momentarily during cranking only.


The engine catches when the key is turned and the starter kicks in as normal, however as soon as I let go of the key the engine cuts off.
This takes me back to the start-by-pass circuit.
Starter motor active..... we have ignition!
Starter motor inactive..... we have NO ignition!


If I pump the key to keep the starter engaged the engine keeps running... obviously I only did this to test..
Not a good idea..... but you did see the results.

So I started to check and replace things.
Not a good idea without using the P of E ..... IMO.
Best to change one item only at a time when trouble-shooting.
Test.... and if no change has been confirmed...... move to the next.


So far I replaced the ignitor in the distributor, new dist cap, new rotor, added ballast resistor thinking its a coil issue, even replaced the coil. Also checked fuel pump and also put on a new carburetor . Still starts then cuts off.
Again... I go back to the start-by-pass circuit.

Click to expand...

The ignition switch shoud be powering the ignition system so that a "rope start" or "push start" would fire up and run this engine.
IOW.... run without any starter motor at all.

Does this boat have an ignition system safety lanyard switch by chance?????
If so.... the lanyard clip must be in place!




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So what was the result here?