Ive been having this problem for a while and now I want to resolve it. I dont get a consistent spark from my coil while cranking the engine. I have a MSD magnetic picup distributor, and 6AL box. I check the distributor for rust around the pickup and there is none. If I plug in another distributor and spin it slowly (30 rpm) I get a spark. I removed the original distributor and plugged it in and spun it (again about 30 RPM) slowly and I get a consistent spark. I have the MSD box wired so it gets power through a relay that is turned on when the key is in run and start. The only thing I can think of is I have the heavy red wire for the MSD box connected to the battery lug on the starter and there may be a big voltage drop during cranking. The weird thing is that both motors are wired identical and this problem only happens on the starboard motor. Does anybody have a clue what may be going on?

The first thing I would do is swap the MSD boxes from one side to other and see if the issue follows the box.

+1 to Griffs suggestion. The other thing you may want to try is to google "Msd troubleshooting". I know that there is good info on msd's web site regarding troubleshooting and if I recall correctly one of the test they suggest is to unplug the distributor lead from the box, turn the ignition on and jump the 2 post in the distributor lead on the box side with a small piece of wire. If the box and coil is good you'll see it fire a spark through the coil wire. If there's no spark....swap out your coil with another one and retest. If it fires a spark...you have a bad coil. If it doesnt I would start looking at your box or distributor as the culprit. Just put a spark plug on the end of the coil wire. That's the easiest way to test it. I would also check for voltage drop on the msd battery wire (big red wire) and the msd trigger wire (smaller red wire) using a v.o.m. It is possible that your relay could be bad or on its way out. I've seen relays do funny things. I hope some of this info might be useful to you but as griff stated, switching out the box, etc... from the other side to see if the problem carries over might be a better idea. It just depends on how difficult it is to disconnect and reconnect the components on the other motor. Bestt of luck, Mark!

mine did the same thing,,it ended up being the magnetic pick up,,replace it fromf summit for 28 bux..

major problem with the "junk" chinese pickups in dist. !!!! ols ones lasted new ones don't...hope they get issue fixed...boxes love to fail whenever they feel like it...

Make sure you have a good ground to the MSD box. Bad grounds are the common cause of MSD failures.

True Dat!!!

I just had two MSD Distributors "rebuilt" by MSD. I have two sets of them and send them back every 4 or 5 years when they get all rusty inside, so I have a rotation working... It's actually a good deal. You get them back, they have all new stuff in them and a new cap and rotor. It cost me $238 including shipping for both of them.

Had my engine guy throw them in for me one afternoon. I take the boat home, drop it in the water, fire them up and head out for a quick blast. The boat idles fine. I go to get on plane and one of the engines starts popping and spitting @ 2000rpms. I head back in...

I checked the timing, perfect! Advance, perfect. Head back out, same issue. So now I'm thinking WTF!!! I should have swapped the distributors at this time, but that would be too easy. I throw one of my spare Crane ignition boxes in there and head back out. Same issue. Change out the coil, head back out and the same thing. Finally, we put the old distributor back in the boat and the phucker runs great.

From what I can see, there is just the metal "wheel" and the pickup in the distributor (I'm running them in "locked out" mode). So it has to be the brand new piece that they installed. I called them and my 30 days was up, but they gave me an RMA number to send it back so they can fix it.....and charge me for it.

Just a FYI, if it is the MSD box you can send it to them and they will rebuild it and send it back for 75 bucks or less. Last one I sent them ($35 eBay find) came back with a new board and all new wiring (longer then original). Basically a new msd box in an old case for a 110 bucks.

Blue boxes cannot be repaired FYI. They are disposable. They are completing encapsulated. MSD Direction packet and Website have different tests to perform to determine your problem. very usefull. I have had 2 boxes quit, one also melted. Not great reliability. I have heard that you don't want them powered or grounded from your starter. Also don't want any stereo "noise" involved in the ignition circuit if at all possible. Just my 2 cents

All of my MSD parts are at least 7 years old if not older, so having an issue with newer stuff is not the case here. I also have spark when I ground the white wire and when I connect the wires from the distributor. I also have spark when I plug in another distributor and spin it by hand. The issue is intermittent spark when cranking. The MSD box is grounded to the block BUT the power is taken from the battery cable post on the starter and NOT the battery itself.