starter wont disengage

[89se-5]

my buddy has a 1991 nissan d21 v6 pickup that i bought a new starter for installed the starter and it started the truck but then would not disengage even with the key out of the ignition the starter still would not stop. So i completely removed the starter installed a new starter relay and installed the starter again and as soon as i attempt to hook up the negative battery cable the starter started spinning even with the key not in the ignition what the heck is going on?

[bradrhale]

ignition switch is toast in the start position would be my first guess. not familiar with nissan but if it has a remote mount starter solenoid, i would also check to see if it is stuck in the closed position also.

[89se-5]

no remote mount solenoid, but is it possible the starter is bad? it was a re-manufactured. and it took me to start the truck for it to start spinning at first and now it wont stop so shouldnt it have just started without the key the first time too? if the ignition switch is fried i mean?

[bradrhale]

best thing to do is to check for voltage at the solenoid with the key off. if you have power there with the key off, than the ignition switch is the culprit. if no power lies there but starts as soon as you hook up the starter and reattach the battery cables, then i would suspect the solenoid on the starter. this is all assuming that the relay is is good operation as well.
what was the reason for the original change of starters?? is it possible that the old one went out due to this same problem?? if so, i would suspect the switch.

[89se-5]

so last night after installing the new starter and it staying on i completely took it off got the new starter relay put that in and put the starter back on and all i had to do was touch the negative cable back to the post and it started sparking and the starter engaged again without any keys so i know the solenoid is getting power w/o a key BUT this never happend once before the new starter the old one was bad and had to be tapped with a hammer or the truck had to be bumped started to get it going which makes me believe the ignition switch is not bad and rather that the rebuilt starter is but i dont know if a rebuilt starter would act in this way or what else it could be

[bradrhale]

if it has a side mounted solenoid, than yes it is possible that it is bad. i would be suspicious of the new starter as well. might try taking it back and explaining to the parts company as to what the problem is. there should be little problem if it is indeed a solenoid problem.

[89se-5]

yea the new starter came with a new solenoid so i told my buddy to try swapping it with another cause that was the only other thing i could think of

[crabtruck]

Couple thoughts...
If you don't do the basic voltage checks
and disconnect the wire from key to solenoid before connecting battry,
you may be doing a lot of unneeded part swapping and store runs.
Many places will bench check a starter for you,
seems a flagrant problem like a stuck solenoid would show up.
It is possible the original "bad" starter that had to be hit to run
may have been caused by the bad key/constant hot short.

this is the AT but may be of help...