351 windsor intermittent starting issues

[jfw432]

I have an 86 Dixie Super Skier 299 with a Ford 351w engine in it. The engine runs good but somewhere the wiring is a little screwed up. It always cranks strong but every now and then, the plugs won't fire.

The first time this happened, I replaced the fuel filler and had to replace the grounding wire running from the fuel filler to the tank. Since this was a serious issue, I ran a dedicated ground wire from the tank to the battery and that fixed it. I installed a radio next and everything worked fine. The boat sat all winter while I was restoring it. I didn't touch any wiring and after being winterized and sitting for 4 months, it fired up instantly and ran like a champ. A couple weeks later it wouldn't spark again so I just pulled the face plate off the radio and it fired right up. Lastly, 2 days ago, it wouldn't fire again so I completely disconnected the radio and never got it going. However, the very next day it ran....

Does anyone have a wiring diagram for these engines? I'm sure there are some since it's a normal truck engine but I can only imagine those would have hundreds more wires that boats don't have that would make things confusing. My plan it replace all of the wire connectors that I can find in hopes that a couple of them are just corroded and the temperature and weather are affecting them but it would help to know what they all do while I'm in there.

 

[Don S]

Re: 351 windsor intermittent starting issues

Is this an OMC? If so, what outdrive? Problem is, OMC didn't use the 351 in 86. OR, is this a straight inboard, if so, who marinized the engine? The marinizer is the one that's going to have the wiring diagram for your setup.

One point, the engine should have a ground cable to it, from the - battery post to a stud on the flywheel cover. The engine should have all the engine grounds on it, the tank ground is only for the fuel gauge and static grounding the tank and should have absolutely nothing to do with the ignition system.
I would be looking for missing grounds on the engine or under the dash, under the dash problems are usually caused by improperly wired accessories added by someone.

 

[Bondo]

Re: 351 windsor intermittent starting issues

Ayuh,... Who marinized this 351,..??

Merc,..??
OMC,..??
Volvo,..??

That'll determine it's wiring...

 

[jfw432]

Re: 351 windsor intermittent starting issues

Yeah it's a straight inboard and the main grounding wire is connected at the starter which of course is bolted to the engine. The engine was done by pleasurecraft. I'll start searching that as well...

 

[jfw432]

Re: 351 windsor intermittent starting issues

Really? Even in most cars I've seen, the negative cable is hooked directly to the starter because that has the highest current draw.

 

[mkast]

Re: 351 windsor intermittent starting issues

Do you mean the negative battery cable is connected to one of the starter mounting bolts?
You might find a positive battery cable connected to the starter relay, but not a negative cable.

 

[jfw432]

Re: 351 windsor intermittent starting issues

Sorry... The cable going to the starter was black but after tracing it down, it's actually a positive wire coming from the solenoid and the ground is right above it on the block itself.

Ok I went to work on some of the wires this evening. Fuel gauge isn't working anymore and the engine won't fire either.

Some things that I'm able to see as abnormal: The coil is getting warm even though I only cranked the engine for 1-2 seconds. Not sure if it was warm before I started cranking or not. The engine doesn't fire when I crank but as soon as I turn the key to off, it fires one of the plugs and tries to start but immediately shuts down. Lastly, whatever this white thing is in the picture below, is getting very hot. The red wire goes to the carb (no idea what that's for). The green wire goes to the starter solenoid. No clue where the gray wire goes.

 

[Don S]

Re: 351 windsor intermittent starting issues

That white thing is a ballast resistor, why it's going to the electric choke, it should also go to the + terminal on the coil. Does it????
You need to trace all the wires and see where they go, once you know and can tell us, then we can figure out if something is wired correctly or not. Without a wiring diagram, who knows it things are set up like they should be or not.
From your discription, I think there are things wrong with your wiring, and it doesn't look OEM either, but who knows.

 

[jfw432]

Re: 351 windsor intermittent starting issues

Nevermind. Don S beat me to it... Wire details coming.

 

[jfw432]

Re: 351 windsor intermittent starting issues

Thanks for the help so far. Everything looked so clean that I thought it was stock wire wrapping so I didn't think about looking into it. Amazing how much time was spent making it look pretty and how little time was spent actually doing the important stuff.

I can only assume this 40 amp fuse by the starter solenoid is a custom deal. Two of the major wires coming from the wire harness were split to go to that fuse.

Just below the wire harness connection is another huge bulge that I can only assume has more half arsed wire connections in it. At this point, I think I've found why things are working intermittently. Tomorrow I'll start soldering and shrink wrapping and see where that takes me.

 

[Lyle29464]

Re: 351 windsor intermittent starting issues

I think I would invest 60 seconds at a look inside the distributor. If the points are closing up on you it would give a lot of the symptoms you have.

 

[jfw432]

Re: 351 windsor intermittent starting issues

I think I would invest 60 seconds at a look inside the distributor. If the points are closing up on you it would give a lot of the symptoms you have.

Thanks for this. I'll look into that tomorrow as well. Might even be worth replacing the cap and rotor while I'm in there since they aren't expensive.

 

[mkast]

Re: 351 windsor intermittent starting issues

The engine doesn't fire when I crank but as soon as I turn the key to off, it fires one of the plugs and tries to start but immediately shuts down.

Sounds like a bad ignition switch.
While cranking the engine, check for voltage on the coil (+) terminal.
The coil should have voltage in both the start and run positions.

 

[Don S]

Re: 351 windsor intermittent starting issues

The engine doesn't fire when I crank but as soon as I turn the key to off, it fires one of the plugs and tries to start but immediately shuts down.

I know why you have that problem, it appears from your pictures that the wiring from your solenoid, ballast resistor, and coil are wrong.
If you look at this picture of your solenoid, the wire from the I terminal on the solenoid appears to be going to the ballast resistor, when it should be going to the + terminal of the coil.

Here is a wiring diagram I put together for you from an old Merc Ford engine. I changed the wiring and added the ballast resistor to show where your wires SHOULD be attached. The colors of the wiring in my drawing is wrong, but you can at least see where the wires SHOULD be going.

 

[jfw432]

Re: 351 windsor intermittent starting issues

I know why you have that problem, it appears from your pictures that the wiring from your solenoid, ballast resistor, and coil are wrong.
If you look at this picture of your solenoid, the wire from the I terminal on the solenoid appears to be going to the ballast resistor, when it should be going to the + terminal of the coil.

Thanks for the help so far... I actually typed out a huge post and lost it so I'll try to recreate it.

The engine fired up this morning after I fixed the large red, white, and black connections next to the valve cover. The white wire actually fell out of the crimp when I took off the electrical tape so maybe it just had a poor connection. The white wire runs to the alternator but I'm not familiar enough with alternators to know which wire does what.

The green wire you say is wrong has me confused. If I run that wire directly to the coil, it would bypass the balast resistor and send 12v to the coil. Wouldn't it? Currently the green wire runs from the "I" terminal to the balast resistor. Here's the tricky part... The green wire is also connected to the purple wire (which goes to the coil) via a twin spade connection. You can see it at the bottom of the balast resistor in the first picture on post 11. The thing about this that I thought was wierd was that everything read 12v until I connected the coil to the resistor. Then it read 6v. Is that just because the voltage doesn't drop until there is a load?

The thing that really bothers me is the amount of heat generated by that resistor. I left the ignition in the on position for about 30 minutes while trying to diagnose why the fuel gauge wasn't working. That resistor just about burned me when I touched it. Is that really normal and you just shouldn't touch it or what?

 

[Don S]

Re: 351 windsor intermittent starting issues

If I run that wire directly to the coil, it would bypass the balast resistor and send 12v to the coil

Absolutely, that's what it's supposed to do. It only happens during cranking so you get full voltage for starting. When you let the key off to run, then the power goes through the resistor.

The thing that really bothers me is the amount of heat generated by that resistor.

Yeah, they will burn you, be careful. They do get hot, that is what resistors do.

PS: it took me 3 tries to post my pictures and text. I kept hitting the wrong button. It got shorter each time. :facepalm: and I have been posting here for a couple of days now.

 

[jfw432]

Re: 351 windsor intermittent starting issues

Absolutely, that's what it's supposed to do. It only happens during cranking so you get full voltage for starting. When you let the key off to run, then the power goes through the resistor.

I thought the coil was only supposed to have 6v normally. What I was saying was.... If I ran the green wire to the coil, I could basically just throw the balast resistor in the trash and the coil would see 12v 100% of the time. Is that supposed to happen?

On a side note, I did figure out that the fuel gauge wasn't working because the sending unit inside the tank had an internal grounding problem. If it goes again, I'll buy another unit before I deal with that horrid fuel residue smell again. Makes regular fuel smell like perfume.

 

[CobiaXL]

Re: 351 windsor intermittent starting issues

Sounds like a bad ignition switch.
While cranking the engine, check for voltage on the coil (+) terminal.
The coil should have voltage in both the start and run positions.

I had bad ignition switch and motor would crank and crank till i left off key and then it fired up.Something to check

 

[jfw432]

Re: 351 windsor intermittent starting issues

The ignition switch is less than a year old and I've checked it with a multimeter when the engine didn't fire to make sure it was working correctly. I still have the old switch though so I may give it a shot if I have a problem again.

 

[Lyle29464]

Re: 351 windsor intermittent starting issues

I think their was a mix up when talking about the ignition wire. The wire from you key switch goes to the 12V side of the resistor. when your points are closed that is droped to 6 volts or so unless your key is in the start position. It is not unusual for the wire from the I terminal of the solenoid to also hook to the resistor but the other end ( 6 volt side) That would be the same as hooking it to the + side of the coil.