xsboost525

yes, we pulled the main coil plug, jumped it to the cap, and there was no spark at all. im going to pull the ignition mod this weekend and check all the connections a second time and clean the mounting points.

when you say "it will work", is this something you see as being safe? i know it takes away the rev limiter, but not once have i ever hit it or plan on doing that. would setting base timing to 35 degrees be a better choice? also, would you have any of these parts you are describing to me lying around that i might be able to buy from you to keep it as factory as possible and relieable?

Griff

That could easily be a sign of a bad coil as well. You need to check for 12 volts going into the coil when the problem happens. Coils will show signs of failure when they are hot or under a load. Nuetral on the hose most likely will not show a problem if it is just getting weak. Get a volt meter and a copy of the Merc flow chart and keep them in the boat. Actually, the Merc Manual for the 525SC is a great reference tool. I had one, but it went with the boat when I sold it.

My opinion is that Merc made this one the most reliable blue engines ever made with the stock set up. If you are doing any performance upgrades, I see no reason to change to an MSD. My boost was increased and I had a bigger roller cam and still never had any need for an MSD box. It idled fine and that is where an MSD box will help the most.

Running the timing locked at 35* can make hot starts harder and can cause the starter work harder and wear out sooner. It also creates more of a risk of detonation in the low to midrange rpms. I think there are better options. I would get an MSD distributor and try to get the curve set as close to the stock 22* curve as possible instead of locking it at 35*

Keep a rev limiter on it. Going slightly past the 5350 rpms is not a problem. Its when you are running at 4500rpms, catch a wave and all of a sudden the engines zings to 6400rpms.

The real solution is to find and fix the what is wrong. Right now you are just guessing. You probably will not be able to find out what is wrong until it happens again.

No, I don't have any of the parts I talked about other than maybe an old spare coil.

xsboost525

thanks so much for your advice and help Griff! i put a new msd blaster coil on it right after the first time it happened, so im assuming i could take that out of the equasion. the new coil has less than 4 hours on it. i bought a new pickup this week, so im going to put it back together stock for now, and go run it this weekend, and see if the problem happens again. i will for sure be bringing a volt meter with me, and hopefully the pickup will solve the problem. ill update this tread after i take it out and i see if it happens again. and yes, i do totally agree with doing a msd distributor then locking the timing as well. again, thanks to all that responded to help me here!!

xsboost525

ok, so i put everything back stock this weekend, along with the new dist. pickup, and no spark at all. im getting tired of troubleshooting, so im just going to get a msd distributor and quit messing around. anyone have any suggestions on either the msd or another brand they have had good luck with? also, im assuming i should be ordering a dist. for a 454, unless someone has a part number i could go off of.

jeff1000man

I know this has probably been covered, but I really don't want to read all the way back.

Do you have signal from the ignition??

Keep in mind that you can get the whole kit (box, coil,wires,dist) from JEGS for around $600.

Griff

Problem was intermittent and at idle and does not repeat running on the hose. I told him that he needs a volt meter and Merc Ign troubleshooting flowchart to diagnose it when it is happening.

jeff1000man

That flowchart would be helpful.

It could be something moving around while idling, or running, such as the ignition switch developing corrosion, corrosion inside the 10 pin plug, frayed purple wire, or the little ground wire that runs back and usually hooks to the solenoid block.

It could be something really stupid, and it's the fact that it is intermittent that makes one thing it might not be in the coil or dist, but just in the main harness or behind the dash.

Maybe if he ran a jumper wire from the battery, or main power block using a long wire and 2 aligator clips to bypass his ignition by hooking the other end to the hot side of the coil. (basically simulating the job of the ignition/ signal wire). Test the boat and see if this helps the situation. If it does not, the problem is on the dist/ coil side of the circuit. If it helps, he would need to go back towards the dash with the problem.

Hope this helps.

Good luck

xsboost525

Jeffman, can you explain what you are talking about with jumping the coil a little better? i would like to try this to see whats going on.

jeff1000man

Basically, there is a purple wire that comes out of your main harness. That purple wire splits and turns on the coil, and also runs to the switch side of your alternator. This is the signal wire from the ignition switch that is hot in the ON position.

This circuit can be bypassed by attaching a lead to the hot side of the battery, and to the terminal on the coil that this wire is attached to. THis bypasses the ignition switch ON position. You will not be able to kill the engine once it is running until you unhook the jumper wire. Sometimes there is a "+" on the coil. THis is the terminal that the purple wire attached to.

If your problems go away with this jumper wire in place, then your problem is not in your ignition system, your problem is somewhere in your wireing harness, or ignition switch or behind your dashboard.

Good luck. Call me if you have anymore questions.

Jeff 832439.5304

xsboost525

i will try that this weekend. if you really dont mind, if i have any problems, i will take you up on calling you when im working on it?