Alternator Output on '02 8.1L?

[prostar205]

Does anyone know the alternator's amp output on a 2002 L18 engine?

[Engine Nut]

Does anyone know the alternator's amp output on a 2002 L18 engine?

If the alternator is painted black, has a cooling fan behind the pulley and says Leece-Neville on it it is a 55A alternator. If it is unpainted and dark gray in color it is a Delco 70Amp alternator. Current ptoduction engines use a Delco 90Amp alternator. If you have a 55A, Indmar has a kit to upgrade to a 70Amp.

Engine Nut

[prostar205]

Thanks Engine Nut for the help. You are correct. It is a Leece-Neville, Model 8MR2084K. However, the badge on the alternator states it only puts out 51A.

I think I know the answer to my next question but I post it anyways.

I am installing a new stereo system with two new amps. One is a Kicker KX600.1 Class D sub amp rated at 700W, the other is a Kicker KX850.1 rated from the factory at 1000W. I have two Blue Top Optima, D34Ms, powering the stereo. My question is: Will this alternator keep up? I know the answer is HELL no but I thought I'd ask. Next question: What should I put in its place?

[prostar205]

I think I have solved my problem. I am going to have the alternator rebuilt by an auto electric shop next to my office for $200. They are going to up the output to 120A.

Anyone have any comments - good, bad or indifferent????

[Engine Nut]

Just rebuilding the alternator is not enough! First, make sure they are rebuilding it to marine specifications. Ask them to certify in writing that it will pass the SAE J1171 test that all marine alternators must pass. If they won't or can't do that, do not use the alternator. Second, the current wiring for your charging system must be replaced. Start by removing the orange wire from the back of your alternator and taping and insulating it. Then run an auxiliary orange wire directlly from the alternator to the positive stud on the starter solenoid. You will also need to run a new ground wire from the alternator to the engine block. You should use a minimium #1 AWG for both the positive and ground wires.

Engine Nut

[prostar205]

Engine Nut -

Thanks for the insight. I went over to the shop that will be upgrading my alternator and verified with them that the upgrade will meet the Marine standard SAE J1171. They said absolutely YES.

However, when I asked the about upgrading the wire AWG, they asked what size was on the boat now. I told them I thought it was 8 AWG. They said that was plenty. Any large wire size would introduce too much resistance in the system. Any comments on that???? After my stereo install, I will have plenty of 0 AWG wire left over from the power and ground wires I'm using on the batteries up to the amps.