rb20 s14 wont start by turning key

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JonnyMac
Posts: 4
Joined: Fri Sep 01, 2017 5:17 pm
Car: 95 240sx

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hey guys, ive got a 95 s14 and i just put an rb20 into it, ive had problems along the way but now i cant seem to get it to start by turning the key. itll just click relays then nothing happens. what i can do is jump the starter with a screwdriver and itll start no problem. thing is, once its started it sounds like the starter wont disengage and i really dont wanna mess up my starter. i have changed my relays and they all click when ignition is turned to start. ive also been through every single fuse ive got and still cant find anything. i dont have any of the tranny sensors hooked up (they werent hooked up on the old ka due to plugs not matching :gotme ) so could any one of those be an interlock ? ill be rechecking my wiring again aswell, any help i can get is much appreciated


ca18det_boy
Posts: 1384
Joined: Wed Dec 24, 2003 10:47 am
Location: Homestead, FL
Contact:

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Was it previsously an auto chassis? Did you do the wiring yourself, wiring specialties, or did someone else do it? Are you using an RB20 trans or something else? If you're using a different trans, what trans/adapter/flywheel are you using? Is it an OEM RB20 starter? Did you have the issue prior to the swap? Can you post a video of it starting?

JonnyMac
Posts: 4
Joined: Fri Sep 01, 2017 5:17 pm
Car: 95 240sx

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ca18det_boy wrote:
Mon Jan 15, 2018 9:12 am
Was it previsously an auto chassis? Did you do the wiring yourself, wiring specialties, or did someone else do it? Are you using an RB20 trans or something else? If you're using a different trans, what trans/adapter/flywheel are you using? Is it an OEM RB20 starter? Did you have the issue prior to the swap? Can you post a video of it starting?
1 no it is factory manual.
2 yes i did the wiring myself.
3 yes i am using an rb20 trans, should be all stock but who knows, i didnt break it open and look when i got it.
4 should be ? lmao idk
5 i had the very common give it 2 or 3 times and she'll crank, but what i dont get is this doesnt crank at all.

what really gets me is that i metered at the ignition switch and all wires are getting power when they are supposed to, and i have +12v on the hot side of the starter post and ground on the other. i was thinking it might be the soleniod on the starter so i will pull it off and have it tested.

when i did the wiring, i used info from all the little sources that are still available

JonnyMac
Posts: 4
Joined: Fri Sep 01, 2017 5:17 pm
Car: 95 240sx

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here is the pics of what i used for my wiring

https://imgur.com/a/mQrA5

JonnyMac
Posts: 4
Joined: Fri Sep 01, 2017 5:17 pm
Car: 95 240sx

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*update* well i went to autozone and since the rb isn't from 'merica, they couldn't test the starter since it wasn't in their system of parts. instead we ended up using a jump pack (for a dead battery) and hooked the clips to each post. the starter shot forward like it should (which was neat because i've never seen that in person and wondered how it didn't shear the teeth :woot: ). but didn't spin which i was wondering about but the guy said it was good, so whatever. i also let him know that i'm able to jump the starter with a screwdriver to start the engine, so he figures its gotta be a wiring issue. im a little tempted to run a switch panel for this stuff just so i can make my own circuit, but i don't want to lose security of having a key.

ca18det_boy
Posts: 1384
Joined: Wed Dec 24, 2003 10:47 am
Location: Homestead, FL
Contact:

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Heya Jonny,

Thanks for posting up that info! When they tested it at autozone, did they hook up the power to the 12V constant or to the solenoid? They should have had the ground on the starter case, the positive to the terminal lug, and then a jumper wire from that to the solenoid. If they only put power to the solenoid, that would explain why the starter gear shot out but didn't turn. I have the autozone part number for the starter at my house, I can get it for you if you'd like them to retest it. I'm thinking it's actually your ignition lock cylinder that's the culprit. What I would do to test this theory is have someone with a multimeter at the solenoid lead for the starter. Turn your key like you're trying to start and see if you have 12V switched at the starter. If you don't have it, remove the ignition switch from the back of the lock cylinder and turn it with a flathead and see you have 12V that way. If you have the 12V, then you're looking at replacing the lock cylinder. You might have to do this a couple times in case your switch is intermittent. When I had my VH installed in my S14 everything was cherry. I removed it to move it to another chassis and put an RB25 in it's place, then I had the same problem you did. I ended up replacing everything but the lock cylinder...guess what the problem ended up being. Anyways, I have a new lock cylinder and no problems starting.


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