93 Bayliner 4.3 Mercruiser, won't start

[TeamSorad]

Hi everyone, I have done lots of searching and looking around these forums. I am trying to figure out my boat, everything will turn over and the boat with "run" when I turn the key but as soon as I release the key it dies. So basically it fires up then dies or will run if I keep the starter going. I ran a hot wire from the + on the coil and the boat runs great. I am not very good at troubleshooting (I found the chart from other another thread)

I took the dist cap off and noticed the ignition sensor is the old open style and it looks pretty terrible/bad so I went and bought a new one gonna install that tonight. My other thoughts are the ignition switch or the thunderbolt IV module (It is the second gen with the triangle plate)

Any help would be great, I know there are lots of threads about this and I am doing the old replace stuff till it is fixed (which I don't want to do) but at least I got it down to a spark/ignition problem

Would the sensor in the dist cause it from starting? and I am not really sure what the hot wire to the coil and running means..

1993 Bayliner 2050LX 4.3 Mercruiser stern drive 0d831996 I would love some manuals if they are available

A little back story, I bought the boat last summer with some carb problems put a street edelbrock on and it ran great all summer. Put it away for winter, returned the carb and just bought an oem rebuilt boat carb (4bbl webber style) to get it ready for this summer.. Now the no starting, but started with the hot wire to the coil

 

[achris]

Re: 93 Bayliner 4.3 Mercruiser, won't start

Hi everyone, I have done lots of searching and looking around these forums. I am trying to figure out my boat, everything will turn over and the boat with "run" when I turn the key but as soon as I release the key it dies. So basically it fires up then dies or will run if I keep the starter going. I ran a hot wire from the + on the coil and the boat runs great. I am not very good at troubleshooting (I found the chart from other another thread)

I took the dist cap off and noticed the ignition sensor is the old open style and it looks pretty terrible/bad so I went and bought a new one gonna install that tonight. My other thoughts are the ignition switch or the thunderbolt IV module (It is the second gen with the triangle plate)

Any help would be great, I know there are lots of threads about this and I am doing the old replace **** till it is fixed (which I don't want to do) but at least I got it down to a spark/ignition problem

Would the sensor in the dist cause it from starting? and I am not really sure what the hot wire to the coil and running means..

1993 Bayliner 2050LX 4.3 Mercruiser stern drive 0d831996 I would love some manuals if they are available

Replace the ignition key switch....

(And those 2 statements I highlighted confirm... you're great at troubleshooting... That is an easy fix with the right info.... Thanks...)

Chris.....

 

[Don S]

Re: 93 Bayliner 4.3 Mercruiser, won't start

Sounds like a bad ignition switch to me.
Do the instruments move when you turn the key to the run position? Do they jump to life when you start cranking the engine?

 

[Bondo]

Re: 93 Bayliner 4.3 Mercruiser, won't start

I am trying to figure out my boat, everything will turn over and the boat with "run" when I turn the key but as soon as I release the key it dies. So basically it fires up then dies or will run if I keep the starter going. I ran a hot wire from the + on the coil and the boat runs great. I am not very good at troubleshooting (I found the chart from other another thread)

Ayuh,... Welcome Aboard,... Startin' at the keyswitch,... with the key in the On position,...

Is there power at the ignition terminal..??...

Yer motor is runnin' off the starin' circuit, off the starter....

Yer Ignition circuit is Dead....

Danm,... Shouldn't have talked to the ole lady,.... where'd those 2 posts come from...:facepalm:

 

[TeamSorad]

Re: 93 Bayliner 4.3 Mercruiser, won't start

yes all the lights gauges work if that is what you mean and the fuel/temp etc work. When I ran the hot wire the tach was working when the engine was running.

Would the sensor in the dist cause it from starting? and I am not really sure what the hot wire to the coil and running means..

What about the old rusty ignition sensor in the dist? What does the boat starting with the hot wire tell me? I haven't installed it yet and if I can save the 80 on the sensor and just buy a 20 dollar ignition switch that would be awesome


I just saw that west marine is still open, is there a special ignition switch I need or anything will work?

 

[achris]

Re: 93 Bayliner 4.3 Mercruiser, won't start

yes all the lights gauges work if that is what you mean and the fuel/temp etc work. When I ran the hot wire the tach was working when the engine was running.

What about the old rusty ignition sensor in the dist? What does the boat starting with the hot wire tell me? I haven't installed it yet and if I can save the 80 on the sensor and just buy a 20 dollar ignition switch that would be awesome

If you get the engine running with a hot wire, the sensor's fine...

 

[Don S]

Re: 93 Bayliner 4.3 Mercruiser, won't start

I just saw that west marine is still open, is there a special ignition switch I need or anything will work?

Just a standard 3 position switch is all you need.. Off, run, start.

PS the gauge question was without the jumper wire to you coil.

 

[TeamSorad]

Re: 93 Bayliner 4.3 Mercruiser, won't start

k thanks guys, I went to west marine and bought a couple 3 prong ignition switches. About to go take mine apart, hopefully one of them will fit/work. I assume there will be 3 wires, is there a diagram for dummies to hook this up for my boat? At least which color wire goes where, that would be great. So I'm gonna head outside and replace the switch... Then if that doesn't work I'll try the dist sensor and I'll update. Thanks for all the help/tips

Also as I side note, the carb I bought has an electric choke and I don't see a place to hook that up.

 

[Don S]

Re: 93 Bayliner 4.3 Mercruiser, won't start

Red/purple goes on the B terminal
Purple wire goes on the I terminal
Yellow/red stripe wire goes on the S terminal.

 

[Don S]

Re: 93 Bayliner 4.3 Mercruiser, won't start

Then if that doesn't work I'll try the dist sensor and I'll update.

The sensor is not your problem. When you jumper the coil it works. Jumpering the coil is just bypassing the ignition switch.

 

[choppywaters]

Re: 93 Bayliner 4.3 Mercruiser, won't start

Hi everyone, I have done lots of searching and looking around these forums. I am trying to figure out my boat, everything will turn over and the boat with "run" when I turn the key but as soon as I release the key it dies. So basically it fires up then dies or will run if I keep the starter going. I ran a hot wire from the + on the coil and the boat runs great. I am not very good at troubleshooting (I found the chart from other another thread)

I took the dist cap off and noticed the ignition sensor is the old open style and it looks pretty terrible/bad so I went and bought a new one gonna install that tonight. My other thoughts are the ignition switch or the thunderbolt IV module (It is the second gen with the triangle plate)

Any help would be great, I know there are lots of threads about this and I am doing the old replace stuff till it is fixed (which I don't want to do) but at least I got it down to a spark/ignition problem

Would the sensor in the dist cause it from starting? and I am not really sure what the hot wire to the coil and running means..

1993 Bayliner 2050LX 4.3 Mercruiser stern drive 0d831996 I would love some manuals if they are available

A little back story, I bought the boat last summer with some carb problems put a street edelbrock on and it ran great all summer. Put it away for winter, returned the carb and just bought an oem rebuilt boat carb (4bbl webber style) to get it ready for this summer.. Now the no starting, but started with the hot wire to the coil

I believe I have the manuals for that boat. We put a down payment on a used one from a guy then decided not to buy it. He never gave us our money back so I kept the manuals.

 

[TeamSorad]

Re: 93 Bayliner 4.3 Mercruiser, won't start

The sensor is not your problem. When you jumper the coil it works. Jumpering the coil is just bypassing the ignition switch.

I understand and that totally makes sense, I am taking your guys advice and going with the ignition switch. I am just concerned about the sensor, but def don't want to replace it if it doesn't need it.

Here is a pic of it and you can see how corroded and rusty it is. The cap and rotor are good

http://i1224.photobucket.com/albums/ee378/joshserad/sensor.jpg

Choppy waters I am not sure what you are offering but I would be interested in the manuals. I am looking for the service/parts manuals

 

[achris]

Re: 93 Bayliner 4.3 Mercruiser, won't start

That's pretty cruddy... But a bit of fine emery and the connectors should clean up nicely. Once it's nice and clean, give it a squirt of Corrosion Guard, and it should stay that way....

Chris......

 

[makonnen]

Re: 93 Bayliner 4.3 Mercruiser, won't start

A typical Mercruiser starter / ignition circuit works like this ...

- When you turn the key to the START position, the ignition cylinder sends B+ to the starter slave solenoid and energizes it.
- The starter slave solenoid in turn energies the starter solenoid
- At the same time, B+ bypasses all safety controls and power the fuel pump directly
- When the engine starts and you let go of the key, the key cylinder is in RUN position.
- The circuit changes, the fuel pump is now only powered IF the oil pressure switch on the lower port side of the engine is ON indicating it has oil pressure

This sensor is in a crappy place ... near the bilge. Also, its covered by the exhaust manifolds making it hard to inspect. Also the wire leading to it is a crimp-on. Let me cut straight to the point ... that wire rots off the crimp, or the tab rots off the sensor. When this happens, you crank the engine and the fuel pump bypasses this sensor and primes the carb. The boat starts ... when you let go of the ignition and the key cylinder returns to RUN poisitoin, the fuel pump stops b/c the oil pressure switch is OPEN ... the engine soon stops running.

That is, if it isn't a key cylinder.

 

[Don S]

Re: 93 Bayliner 4.3 Mercruiser, won't start

I understand and that totally makes sense, I am taking your guys advice and going with the ignition switch. I am just concerned about the sensor, but def don't want to replace it if it doesn't need it.

Here is a pic of it and you can see how corroded and rusty it is. The cap and rotor are good

http://i1224.photobucket.com/albums/ee378/joshserad/sensor.jpg

Choppy waters I am not sure what you are offering but I would be interested in the manuals. I am looking for the service/parts manuals

Yes, your sensor looks horrible, but it's working and not causing your problem, otherwise the jumper wire to the coil wouldn't work.

You can download the manual from this link http://www.4shared.com/office/OWg8q3NF/07__GM_V6_83-93.html? for free. But it's not going to help with your current problem.

The fuel pump operation is also not your problem. Jumping the coil does nothing for the fuel pumps,

 

[choppywaters]

Re: 93 Bayliner 4.3 Mercruiser, won't start

I understand and that totally makes sense, I am taking your guys advice and going with the ignition switch. I am just concerned about the sensor, but def don't want to replace it if it doesn't need it.

Here is a pic of it and you can see how corroded and rusty it is. The cap and rotor are good

http://i1224.photobucket.com/albums/ee378/joshserad/sensor.jpg

Choppy waters I am not sure what you are offering but I would be interested in the manuals. I am looking for the service/parts manuals

I was offering the owners manual and the mercruiser manual. I found them right after I posted but saw its for a 2052....sorry.

 

[TeamSorad]

Re: 93 Bayliner 4.3 Mercruiser, won't start

Well it def wasn't the ignition switch or dist sensor, boat still does the same thing. Starts for like a sec then dies. I checked the purple wire and it has 12v when the key is on, so now I am stumped. I checked the fuses and there is a 3amp fuse blown but the rest were okay, not sure what the 3 is or what the rest do

 

[TeamSorad]

Re: 93 Bayliner 4.3 Mercruiser, won't start

Couldn't get it figured out after trying the new ignition switch and dist sensor so I just dropped it off at the shop. Doesn't make sense to me the key switch and coil were both hot at the purple wire, hope it isn't the icm plate.. I'll update when they figure out the problem, was hoping to be boating this weekend

 

[mr-steve-jones]

Re: 93 Bayliner 4.3 Mercruiser, won't start

Silly question... You got good oil pressure?
Like Makonnen said the engine cuts out if the signal from the sensor is bad, or it has no oil pressure.

 

[TeamSorad]

Re: 93 Bayliner 4.3 Mercruiser, won't start

yea def has oil pressure and I'm pretty sure that sensor only cuts out fuel not spark.. There is plenty of fuel, just not sure what is going on. The motor starts/rumbles for like a second then dies. Boat is already at the shop and I'll update with what they say is the problem. Not a fan of shops, but couldn't get it figured out. Gonna suck if it is something I overlooked being a dummy, waste of 110$