mentordrift
05-05-2012, 07:30 PM
I did some searching, and narrowed down the problem that I am having, and mostly need to just confirm the root cause before I end up buying a new battery
car is a 1995 240sx, engine is a S1 RB25DET
relevant mods:
safc hard wired per manual
dual pusher fans wire per manual, fused
300zx maf, wired per JWT diagram
I was originally having a charging issue the engine, that warranted a pull and fix of any and all wires on the upper and lower harness. All connections were soldered, and any issues on the harness itself was ruled out after this. It is grounded properly at the engine block, firewall, intake manifold and frame area.
I have two alternator; both were checked at Autozone on the bench machine, and both passed, I am currently running a Quest 110 amp unit, but also have the RB25DET unit (just in case). The alternator plug is in good condition, the connection is solid. The alternator ring/bolt connection is tight and also a solid wire. The alternator is NOT grounded to the engine block, I noticed this when pulling the starter for the next.
The starter is good, it passed all three "tests" that are run at AutoZone, but it DID spark (a fairly big spark) when the test was started, but did not continue to spark while the test proceeded. The starter is a '66 Datsun 411 unit that bolts directly up to the RB25 engine, and I have NEVER had an issue with it since the day we installed it about 4 years ago. The gear extends, etc.
The battery is what I am assuming is where the problem lies. It has been jumped directly to the battery enough times over the last 6 years (battery date 6/06). HOWEVER - after putting the battery itself on a 12v charger for a few hours, the engine starts on its own power; runs GREAT, and has no issues, SAFC showing a full 14~ volts while running, no break up at higher rpm, no misfires. After shutting the car off, the battery is dead. Not enough juice to start the RB25. After charging it again for another hour or so, it doesn't start the car again. AFTER putting the battery into a friends KA24 vert, he could start his car on MY battery...
We can start the car no problem by jumping from the starter, and the car will stay running until the key is turned off.
I have NO idea where the voltage regulator is on these cars. Never had to change one. IF this is what I need to check, how do I do so?
I am for sure getting fuel and spark at start.
I am for sure not getting any grounded wires.
I am for sure using a good starter, alternator, and all connections are good.
Can ANYONE point me in the right direction, before I decide that the battery is just simply not capable of starting the car anymore. Things to check, things to look or listen for, things that should be there that might not be?
I just need help before I take this car to someone that will butt***e me for labor charges.
car is a 1995 240sx, engine is a S1 RB25DET
relevant mods:
safc hard wired per manual
dual pusher fans wire per manual, fused
300zx maf, wired per JWT diagram
I was originally having a charging issue the engine, that warranted a pull and fix of any and all wires on the upper and lower harness. All connections were soldered, and any issues on the harness itself was ruled out after this. It is grounded properly at the engine block, firewall, intake manifold and frame area.
I have two alternator; both were checked at Autozone on the bench machine, and both passed, I am currently running a Quest 110 amp unit, but also have the RB25DET unit (just in case). The alternator plug is in good condition, the connection is solid. The alternator ring/bolt connection is tight and also a solid wire. The alternator is NOT grounded to the engine block, I noticed this when pulling the starter for the next.
The starter is good, it passed all three "tests" that are run at AutoZone, but it DID spark (a fairly big spark) when the test was started, but did not continue to spark while the test proceeded. The starter is a '66 Datsun 411 unit that bolts directly up to the RB25 engine, and I have NEVER had an issue with it since the day we installed it about 4 years ago. The gear extends, etc.
The battery is what I am assuming is where the problem lies. It has been jumped directly to the battery enough times over the last 6 years (battery date 6/06). HOWEVER - after putting the battery itself on a 12v charger for a few hours, the engine starts on its own power; runs GREAT, and has no issues, SAFC showing a full 14~ volts while running, no break up at higher rpm, no misfires. After shutting the car off, the battery is dead. Not enough juice to start the RB25. After charging it again for another hour or so, it doesn't start the car again. AFTER putting the battery into a friends KA24 vert, he could start his car on MY battery...
We can start the car no problem by jumping from the starter, and the car will stay running until the key is turned off.
I have NO idea where the voltage regulator is on these cars. Never had to change one. IF this is what I need to check, how do I do so?
I am for sure getting fuel and spark at start.
I am for sure not getting any grounded wires.
I am for sure using a good starter, alternator, and all connections are good.
Can ANYONE point me in the right direction, before I decide that the battery is just simply not capable of starting the car anymore. Things to check, things to look or listen for, things that should be there that might not be?
I just need help before I take this car to someone that will butt***e me for labor charges.