2001 mpi 7.4l hardly a spark

[Bermuda Boater]

Hi all,

have twin merc 454 mpi 7.4l inside engine room. Starboard starts just fine but port wants to start but doesn't.

Port engine cranks over but not as it should. Almost as if the batteries are dying but they are good batteries. Even ex hanged the batteries with the starboard engine and still have same problem. I changed plugs, new coil, new leads and even cleaned the deposits from the distributer. Still have that dying battery start. Also when attempting to start I get a loud continuous beep that comes from the co sensor that doesn't ant off until I turn off the battery switch.

I was thinking this May be a starter or starter solenoid problem? Opinions would be greatly valued!!

 

[Bermuda Boater]

Also failed to mention that there is a small puff of smoke that comes from where the red battery wire connects to the starter.

 

[Bermuda Boater]

Stupid me, engine started before but because the run of it was harsh, partly because distributer was not lined up, could this also in any way have an effect on my situation?

 

[magstang1]

Disconnect that red wire clean the terminal and reconnect it. I bet it's loose and corroded. I'll also bet that after you try to start the engine the terminal is blazing hot.

Disconnect your batteries first.

 

[magstang1]

Distributor not lined up? Did you mess with the timing? If you did, time for a timing light.

 

[Bermuda Boater]

Distributor not lined up? Did you mess with the timing? If you did, time for a timing light.

It might not be to be honest. But will that effect the way she is starting like the batteries are dead?

will check and clean that terminal tomorrow and let you know my findings.

Thanks

 

[Gary Hill]

One clue that you need to consider is that CO sensor. Typically when they go off like that they are not getting enough voltage. This along with that red wire and puff of smoke requires looking into electrical issues as well. The starter probably needs to be looked at as well.

 

[scoflaw]

Stupid me, engine started before but because the run of it was harsh, partly because distributer was not lined up, could this also in any way have an effect on my situation?

Absolutely, timing too advanced.

 

[Bermuda Boater]

Go you covered. Will look at today.

 

[RubberDuckeeToo2]

Last year, I was told that I needed a new starter because of similar symptoms. Turned out that a bad tach was sucking the juice out of the computer and ignition system keeping the spark plugs from firing. Took a whole season and four marine mechanics to find the problem and at least two of them had a computer hooked up. Since then, I have discovered that certain of the tachs are a weak link in the ignition.

Gene

 

[Bermuda Boater]

Ok guys. Had a look yesterday and turns out my timing was way off. I've since moved the distributed back a bit and bam, she starts!

Frantic with excitement, i did little celebration dance only to find 3 new problems! Losing coolant, no raw water being pumped and my gear shifting cable broke.

It seems the coolant is leaking from the pump on the engine. Thought it was the hose up front so I changed it and the leak persisted. Took my fingers and followed the leak and I believe it is coming from one of the gaskets. Will check further today.

As as for the raw water, believe it is either blockaded or the impeller, will check today. Now the cable, the clip little clip that holds it to the morse has bent and broken off. I may do a poor mans fix and rig something to hold it together temporary or wait till Saturday to but a new one. Seeing as today and tomorrow a re national holidays here in Bermuda Saturday is the next working day for the island. Wish me luck!

 

[Gary Hill]

Alrighty then, good luck!

 

[magstang1]

Those water pumps have a weep hole and are designed to leak when the inner seal breaks. The inner seal keep the coolant off of the bearings. If the coolant is coming from the weep hole your bearings are immersed in coolant and it is just a matter of time before you have a complete failure of the pump.

Investigate closely and quickly.

 

[Bermuda Boater]

Ok guys. Turns out the water circulating pump was finished. Have changed now. Also found the problem as to why there was no raw water being pumped, I connected the wrong hose. Intake to the outtake on the pump. Also fixed the gear cable.

Unfortunately now now the engine will not start at all. One thing though, it started with the faulty circulating pump and the reversed raw wAter hose. Now nothing. Turns over and attempts to start and there is a spark. What am I missing here?

 

[CliffA]

if your boat has shift interrupt switches you may need to check the cable setting.......it is possible that when you made the repair/replacement of the cable the new cable length is not set correctly and the shift interrupt switch may not be in neutral.....

cliff

 

[Bermuda Boater]

She is in nuetral. Engine tries to start, but doesn't. I did notice the plugs are a tad bit dry, actually completely dry. Begining to think something is up with the fuel now. Not sure why given that the previous plugs were wet and she started and ran before. Have filled the tanks up just to be sure and still no start.

Also thinking of calling a mechanic (don;t really want to pay that kind of money) to run a diagnostic for me.

 

[2000SR380]

Running through this thread, it sounds like you corrected a timing problem, a water pump problem and a Nuetral Safety Switch issue. Now you are down to a different symptom. Take a deep breath and start new. The problem now described is why God invented Ether/Starting Fluid. A great many problems with engines (of any kind) start with the basics. Fuel, Air, Spark Compression. Plugs are a 'tad bit dry' would indicate no fuel. Squirt a bit of ether down the throttle body, crank the engine. If it lights, you have a fuel problem (possibly fuel filters/ fuel pick-up/fuel pump). No change you have already covered air restriction and fuel, so you are down to compression or spark. Most Starting fluid can be had at your local automotive supply for $3-$5 a can, and it would be hard to pay over $50 for the very best stuff (way overkill for this project).

 

[CliffA]

you didn't accidently knock the 'kill switch toggle' at the shifter down while working on the shifter cable did you?....happened to me once.....took a few hours and a lot of colorful language to figure it out.....

sounds silly but you may want to verify that the plug wires are in the right position (firing order) on the distributor cap.....if the distributor was ever removed from the engine it could have been put back in at a different position from the original position which changes the location of the number one position on the cap which changes how the plug wires get attached to the distributor cap....to verify this put the engine on Top Dead Center and look at what position the rotor is pointing......it should be pointing to the #1 position of the cap.....

cliff

 

[CliffA]

did you find the problem?

cliff