Engine Cutting out

[Shansta]

Hello,

Hoping someone can give me some advice.

I have 1976 75hp Chrysler that seems to be stopping when hitting waves. Last week I went for a fish and on the way back in i hit a small wave and the motor stopped but started straight away and I was off.

This week I went out and travelled roughly 4km and everything was fine (water was pretty flat). On the way back in the water was choppy and waves were roughly 50cm-80cm - but everytime I hit a wave the motor would either stop or putter for a few seconds and then stop, like it was running out of fuel. At first it would start back up but as soon as I put it in forward it would stop, this happened several times. After leaving it off for a minute it started back up and I was going at roughly 5 knots, when I picked up speed and hit another small wave it would stop again. Same thing would start and putter and stop, then turning the key would do nothing, not even turn it over. Leaving it for 5 mins the key would work again but as soon as I put it in forward it would die. After a few attempts, I worked out that if I pushed the key in for choke it would start and go forward.


It seemed to me like it was not getting fuel or there was air in the line... not sure. But the key not doing anything sometimes when turning it on leads me to think maybe it is something electrical. A relative also advised me it could be the floats in the carburettors sticking. Before I rush out and get a mechanic I thought I might change the fuel hose but was hoping someone has had this problem and give me some advice.

I have started the motor up today and seems to be doing the same thing but without hitting any waves lol

I added some videos to youtube
Chrylser 1 - YouTube
Chrylser 2 - YouTube

Thanks,
Shannon

 

[jerryjerry05]

Re: Engine Cutting out

First do a comp/spark test.Probably nothing wrong but just to be sure???
Then check all electrical connections, key switch too.
Plugs burning ok?
It dies suddenly so it could be electrical.
Pull some gas from the tank and check for water.
Check the fuel pump diaphram.
Profile,Location?? You might be close to someone who can help.
Ethanol?? If you burn gas with ethanol it's best to install a filter before the fuel pump/carbs.
Check the float bowls for dirt.

 

[Frank Acampora]

Re: Engine Cutting out

You may have multiple problems:

First, although it is impossible to tell idle speed without a tachometer, it is possible to say that your engine appears to be idling too low.

Clean the sparkplugs or install new ones and try again. If you have a tachometer the idle speed should be 700-750 in the water in forward gear. This will usually be up around 1000 RPM in neutral.

If you don't have a tachometer, when put in gear, the engine should "clunk" but not sound like it is crashing into gear. Not too much noise, just a solid clunk. Obviously, it is best to set with a tach. Your engine can use a regular 12 pole tachometer made by Teleflex and other brands. The white wire is signal to the tach.

Secondly, your engine has the electronic box power wires running up over the block and under the flywheel. It is not uncommon for these wires to rub on the flywheel and short out. The engine dies and will restart, sometimes almost immedisately, sometimes you need to wait a bit until the circuit breaker cools. Check the red and blue wires that go up under the flywheel for signs of rubbing.

Do not mess with the carbs at this point. If you do need to reset them, read and understand the sticky at the top of the forum page FAQs: Synchronizing timing and carbs.

 

[Shansta]

Re: Engine Cutting out

Thanks guys. I am in Melbourne, AU

I did do a cold compression test not long ago and all 3 were at 150. I will do one again.

I will check out your suggestions.

I'll let you know how I go.

Thanks heaps.

 

[Shansta]

Re: Engine Cutting out

Worked out the problem. Loose positive wire at the ignition.

I did a compression test, this time why the motor was warm and all three showed about 100-105 psi.. I did a test a month ago when it was cold and they all showed as 150.. Which one is correct? The motor always starts first go so I hope its not on the way out :/

Also, can you guys tell me what round thing in the picture is? Has a black and orange wire connected to it?


Thanks

 

[jerryjerry05]

Re: Engine Cutting out

That's an overheat alarm buzzer.
Take a screwdriver and short it out at the engine/sender and see if it makes any noise.Key on.
The comp results could be the guage is reading wrong.
105# isin't great but probably the guage. Get a different one and try again.