4.3 Mercruiser Starting Trouble

[goblenick]

I'm fairly new to the boating world so bare with me if anything is lacking/incorrect.
Last season I bought an '89 Sea Ray Bowrider with a 4.3 Merc (175hp). At the end of the season, I had some problems with it flooding and being a little hard to start so I rebuilt the carb. Never took it for a test run, but did fire it up to make sure it worked then parked it for the winter. I dewinterized it over the weekend, hooked up the muffs, and fired it up. Started and ran with no problems. Ran it for 15-20 minutes then decided to take it out. On the ramp, it started first try. Kicked it in reverse and it died out. Tried numerous times but could not get it to kick over again. Thought it may have just flooded out again, but I couldn't start it today either. I've ordered a new coil, plugs, wires, cap and rotor to put in this weekend (the boat could use these anyway). If this doesn't fix it I'm stumped. Why did it start up on the muffs and the ramp fine then die out and not come back to life???????
Any help is appreciated.

 

[Bondo]

Re: 4.3 Mercruiser Starting Trouble

You're going to have to Figure that Out.......

It takes Fire, Fuel,+ Compression,... At the right Time......

If it Don't Start again,....
Pull some Sparkplugs,+ See if it's Firing,+ If there's Fuel present......
Once We know the Missing piece of your Puzzle,.....

Then We can get you Fixed Up....

 

[I/O WALDO]

Re: 4.3 Mercruiser Starting Trouble

I smella lower cable.

 

[tystick]

Re: 4.3 Mercruiser Starting Trouble

I smella lower cable.

lower cable? please elaborate - is this a merc related issue? I have a 4.3 merc with exactly the same symptoms.

the distributer cables?

 

[goblenick]

Re: 4.3 Mercruiser Starting Trouble

You're going to have to Figure that Out.......

It takes Fire, Fuel,+ Compression,... At the right Time......

If it Don't Start again,....
Pull some Sparkplugs,+ See if it's Firing,+ If there's Fuel present......
Once We know the Missing piece of your Puzzle,.....

Then We can get you Fixed Up....

I'm going to try pulling the wires off this weekend when I get enough time away from work and see if I'm getting fire. If fire is good then the plan is to pull the fuel line off the carb and see it the pump is supplying what it needs to. If neither are bad, then I'm in trouble....this is where it starts to get intimidating.

Waldo, I'm with tystick on the cable thing...what do you mean by lower cable?

Thanks for the help guys.

 

[BRG25]

Re: 4.3 Mercruiser Starting Trouble

You didn't accidentally pull the safety lanyard did you?

Make sure you are really in neutral and the shift interrupt switch isn't stuck.

 

[Haut Medoc]

Re: 4.3 Mercruiser Starting Trouble

I agree with Waldo & Brg.....
Check the shift interrupt swich, if it is stuck, the engine will never start.....​

 

[goblenick]

Re: 4.3 Mercruiser Starting Trouble

If it is the swith on the shift cable, wouldn't that stop it from cranking altogether? The starter kicks over fine and cranks with plenty of power. Does this swith just cut the power to the coil and not the starter?

 

[BRG25]

Re: 4.3 Mercruiser Starting Trouble

Check out this link...

http://www.homestead.com/dolphinmarineservice/Cable.html

 

[Haut Medoc]

Re: 4.3 Mercruiser Starting Trouble

If it is the swith on the shift cable, wouldn't that stop it from cranking altogether? The starter kicks over fine and cranks with plenty of power. Does this swith just cut the power to the coil and not the starter?

No....
Yes.....
That is a good link, BRG 25......​

 

[tystick]

Re: 4.3 Mercruiser Starting Trouble

connections at the distributor can cause this type of intermittent problem

ie: corroded pin at the distibutor.

 

[180shabah]

Re: 4.3 Mercruiser Starting Trouble

The shift interupt switch, stops ignition, it has no effect on the starter.

 

[goblenick]

Re: 4.3 Mercruiser Starting Trouble

First off, all you guys are stone cold superstar badas*ses for helping me out and I appreciate it.
I guess the plan for the weekend will be to test the ignition for fire first. If there's no spark, I'm guessing I can use a test light on the coil power wire to determine if it may be the interupter switch then go from there. If its sparking ok I'll turn my attention to the fuel system. I'll let you guys know how it works out on Saturday. Thanks again.

 

[180shabah]

Re: 4.3 Mercruiser Starting Trouble

Waitin' to hear what you find out.

 

[I/O WALDO]

Re: 4.3 Mercruiser Starting Trouble

Shift cable symptoms-Boat runs fine on hose without shifting into gear.Put it into gear and it dies.(with drive down,in or out the water)If you now get no fire at coil wire try moving the shifter (engine/ig. off,in gear)from foward to rev. several times and stop in neutral.Now,sea if you have fire when crankin at the coil.If so ,lower cable/shift shaft binding symptoms.If knott,time for some more tests.The shift interrupt switch grounds the neg.side of the coil for an instant when shifted to reduce the load on the clutch dogs.A tight cable can cause the switch to stay engaged when it should not be @ no fire!

 

[goblenick]

Re: 4.3 Mercruiser Starting Trouble

Ok, so I sacrificed a little sleep and probably pissed off the home owner's assosiation today, but I couldn't wait. I went and grapped my boat from the storage yard and parked it in the driveway and pulled out the test light. With the key in the run position, the ground to the coil is bad. Positive side is good. Does this confirm the cable problem? I didtn't have time before work to do any more than that. Is there anything else that may interupt the ground? Also my boat is and Alpha One gen 1...don't know if I mentioned what gen it was before or if it makes a difference.

 

[I/O WALDO]

Re: 4.3 Mercruiser Starting Trouble

Look at the cable shift plate( on the starb. riser)and find the interrupt switch.Move the lever that triggers the switch and see if the switch is off(in center of lever detent)If not,the switch is grounding the coil.

 

[ttree18]

Re: 4.3 Mercruiser Starting Trouble

You didn't accidentally pull the safety lanyard did you?

Lol.... I've done that!!!

 

[goblenick]

Re: 4.3 Mercruiser Starting Trouble

No, the safety lanyard is fine. I went to start her up today and she's magically fixed herself...started up first try. I did check the interupt switch on manifold and it seems to be working as advertised. What the crap is goin on here???? The only thing I can think of is the angle of the boat ramp (I started it in the driveway today) is causing the carb to run out of gas or flood...which on I don't know. Plans are to take it to the ramp tomorrow and see if it does the same thing. If anyone has another theory please let me know.

 

[I/O WALDO]

Re: 4.3 Mercruiser Starting Trouble

Lets sea what it does when put into water into gear!