Since I put my Ilmor in I have on occasions had problems with starting the engine. For some reason it’s never liked starting on just one battery and now it’s not starting at all. I called the nice people at Ilmor and they walked me through checking the engines electrical system; grounding cables, power cables, the kill switch, the gear sector, the starter, starter fuse, and starter relay to name a few with no luck. I had extra fuses and relays so I tried replacing them and still nothing. They thought that maybe my starter is bad so they’re overnighting me a new one; for free I might add. Yesterday I decided to remove my starter and my starting battery and have them tested. I took both of them to Advanced Auto Parts and believe it or not both passed. The starter worked fine and the battery showed good load. I put the battery and starter back in and still nothing. Now I figure it’s got to be a wiring issue right? I grabbed my amp meter and I starter testing. Both batteries showed 13.95V, the starter showed the same. While testing the starter I had my buddy try to turn it over and when he did the volts dropped to a little over 4 volts until he let off the starter and then it went back up the 14V. Also we noticed that before we tried starting the engine the volt meter on the dash was showing 14V and after we tried starting it dropped to the bottom, and the whole dash started acting like it wasn’t getting any power. It stayed that way even after we disengaged the starter but after we turned the key off and turned it back on it again it acted fine and showed 14V. Could it be that somewhere between the engine and the ignition switch something isn’t grounded right? I checked the grounding strip below the dash and everything seemed fine, nothing loose. I then looked in the engine compartment and found another grounding strip on the front of the engine compartment on the Starboard side and now I’m wondering if this is my problem. Does this look right or should there be another grounding cable on the left side?

That strap is for your dash and accessories. you are losing main power to both the starter and that point.

Could be the positive or a negative cable. If I were you I would hook to the ground post right at the battery. Then starting at the heavy positive cable work your way from the battery out, checking the voltage when cranking. Somewhere u will find the bad cable.

If you don't find it on the positive, swap the leads and do the same on the ground cables.

I'll give that a try but is that strip grounded right?

Looks like the ground strap.

that's a bus bar . . . meaning the hot side of your electrical. . . . the positive side. Each of those connectors are numbered. The more than likely go to your dash panel.

If you put a ground cable to that other side, you'll have a nice spark show or a blown up battery


If you're having problems starting, check the grounding cable that's on the block

Good to know! I was under the impression that yellow meant to was a ground. I've tried checking all the ground cables that are attacked to the engine.

I would try hooking a test light to the smaller wire on the starter solonoid. When you,turn the key to start the engine the light should light up. maybe bad ignition switch? check the wires on the back of the ignition switch. yellow is ground in my boats engine comp.

I thought if that was a buss bar for positive each line should be fused, if not a short on one small wire and you have a melted wire and fire hazard?

Volt meter from ground to there will tell you.

Good idea on a test light on solenoid.

Found the culprit!! It was the red cable that goes from the battery switch to the engine. We cut about an inch off the end that connects to the battery switch, put a new fitting on it, and she fired right up! Thanks everyone for your help.

Always a bad connection in the main wiring circut with your syptoms.

The above pic is a ground buss. (notice the no fuses..... and the1 green wire, unless someone really has no business doing electrical wiring) The large heavy wire on the right end is the grounding feed wire. That's all good.

Yellow is used for DC negative. The use of black wire for negative can be confusing when used on a boat with 120VAC shorepower, where black is hot!!! Yellow eliminates that confusion