HELP!? 351w wont start warm!

Teddeee1981 wrote: I have to batteries now, and will install the second one tonight. Hopefully that will get the coil the voltage it needs at start up. PS. Is the wire from the starter relay a bad idea?

Ted,
It's not a "bad" idea by why do you feel it's needed? PCM never thought it was needed! Find the problem and fix it. Don't forget to get some voltage readings so the problem can be located.

Bri892001 wrote: 8122pbrainard wrote: Ted, That 12 volt "kick start" wire off the starter relay is how we ID intruders from the MC sight!! BTW, where have you been reading about that? I realize PCM doesn't have this, but what does this function do? Just give a hotter spark for start up?

The concept is it compensates for a voltage drop encountered from the high load of the starter when cranking the engine.

Teddeee1981 wrote: How is the coil supposed to get 12 volts still going through the resistor? I know there something im missing here...

Ted,
First, as Tim mentioned, PCM does not use the 12 volts to the coil when cranking. Keep looking for a voltage drop with the meter.

The 12 volt to the coil when cranking is really pretty simple. With the start relay energized, the power to the coil comes from it and is 12 volts. After the engine starts, power to the coil comes from the key ignition switch (run position) goes through the resistor and ends up at the coil at about 9 volts.

BTW, instead of looking at automotive wiring diagrams, take a look in the engine manuals in the ref section. They have wiring diagrams. Very similar to auto but some small differences. Here's one:

LOL NO WAY was i on an MC site!

My nautique is my first boat and will be with me forever!

I googled Coil resistor. Came on to a car site. There was a diagram of what it should look like (or at least what someone believes it should look like).

I took a picture of the screen with my cell. I will post it when i get home see what you think.

You've all been very helpful. I really appreciate it.

Teddy

Teddeee1981 wrote: i read somewhere that there should be a wire running from the starter relay to the coil side of the ballast. Is that true? mine does not have that.

That is not the standard PCM set up, no.

Indmar did that though.

Got it. Will test some more this weekend and let you know how it goes.
Thanks again.
Teddy

The boat came with a battery, i have replaced the battery with a new one (same one though)
It is a marine battery. I believe it is a deep cycle. Not a hundred percent though. I will look again next weekend.

What battery would you recommend?

With a proper battery you think the coil will get the voltage it needs?

voltage drops when hot...

I believe i AM running a deep cycle battery.
Would that be no good?

Im going to test that third wire, maybe it is connected to the ignition switch and should be on the other side of the ballast...

PROBLEM SOLVED!

For now anyway! lol

It was a ballast that runs a wire to the coil.
For some reason it was only running between 6 and 8 volts at start up.
On one side there was three wires. One running to the distributer, one being the power, and one im not sure about. On the other side there was only one wire. It was running to the coil. I always assumed i should leave it, so it doesn't burn out the coil. but a friend mine insisted it won't burn the coil out with 12 volts running to it constantly.

My theory is on the water there was more load, more fuel. Not enough spark.

On land, there was enough spark to get it going.

Thoughts? PS i currently have a different carb all together on it. The same problem happened when i took it out.

Teddeee1981 wrote: One thing i haven't thought of at all is the exhaust manifolds. For all i know they are the originals. I should replace them. Could this really be the problem though?

I don't think the exhaust manifolds would have anything to do with the problem you describe. Very old manifolds may start leaking at the gaskets or develop cracks/leaks but those problems would not give the troubles with hot starts you describe.

thats for sure..when I rebuilt my carb along with the engine, It was almost I month until I got it running fine, I had problem with leaking after shut off, iddle, etc. Major problem was a vacuum leak between carb base and performer intake I put there, solved it a spread to square bore base adaptor from summit...

Thanks Guys!
The carb is off. I'll be taking it in this weekend. Im also going to see if there's a spare around that i can test. See if it is indeed the problem.

Do 74's have anything at all in the way of relays that could affect this?

I know anything electrical can be less conductive when hot. Hence starter motors always acting up more when a car is fully warmed.

Have you checked the exhaust manifolds for leaks? They could be leaking water into the motor and keeping it from firing up. Water won't compress and slower cranking is a sign.