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727 question - won't start in park

Dreadl0ck

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For some reason I can only crank the engine if I'm in neutral - not in park. I guess there's a wire missing somewhere, but this being my first B-body I can't seem to find it. Enlighten me please
 
You might have the wiring harness connector on backwards. Rotated 180 degrees?
 
You might have the wiring harness connector on backwards. Rotated 180 degrees?

The 3 pin connector that goes into the transmission? Thought that was the neutral safety switch where center is to starter relay? Or are we talking about different connectors?
 
The three pin connector is for park and neutral
 
Possibly a linkage adjustment. Try pushing the shift lever to the left & see if it cranks.

Chuck
 
It depends on wich year the tranny is from. Mine from 1964 only has one pin on the park/neutral switch. On "early" 727 62-65 you can drop the oil pan and look at the selector and se if it hits the switch on park and neutral.
 
It's most likely the linkage like clazar said, make sure the shift lever on the transmission goes all the way to park and the pawl engages. May have to unbolt the linkage and start over.
 
I agree, sounds like linkage. The neutral safety is just the needed ground for the relay to engage so if it works in neutral then the switch itself is working.
 
Yes it sounds like just a linkage adjustment or worn and loose linkage. On the 3 pin switch you can put it on either way if it fits either way as the center terminal is the ground for the neutral safety switch and the two end terminals are for the backup lights and it dont care which ends the wires are on. The center pin just grounds the wire from the starter relay coil so if it starts in neutral you know the switch will ground the wire. So its either an adjustment or loose linkage problem. It could still be the NSS that just screws into the trans as it could work in neutral and not park but that is rare. Ron
 
Is this a column or console shift? Both shift linkages have an adjustable rod swivel that you can check for play. Also, there can be excessive movement in the torque shaft bushing that is mounted in a bracket on the transmission, that bushing can be worn out. You can access all of this stuff easily underneath the car on the drivers side of the trans. The linkage diagram is in the torqueflite section of the FSM.
 
Console shifter car - if it's any help to you it's a bit hard (physically) to move the lever all the down to 1 - you need to push it a bit harder for it to move all the way down. I'll check the linkage and report back
 
Sure does sound like linkage adjustment. I always start setting linkage in neutral, check each shifter position by moving the shift lever (column or floor) & move lever on the trans see if the linkage rod drops in cleanly for all positions. Park can be tricky to get the lever on the trans to go into the "park" position & you may have to roll the the car a little to let the park rod to engage the pawl inside the trans.
 
Dug this out.

I have the same problem. Column shift, fully restored car (all bushings are new), electric new, I even changed the NSS switch (both were fine). I have a 1-prong NSS.

I have adjusted the linkage several times like instructed in the FSM. On the first start it fires straight up in Park. Going for a drive, shut off and won't let me start the car again in P only in N.

I don't know what to do else..and I don't want to permanently ground the terminal for safety reasons.

Is there anything I am missing?
 
When you are experiencing the no start issue go under the car and disconnect the rod from th etrans lever. My bet is the lever will move slightly allowing the engine to crank. If this is the case; #1 The linkage is sloppy at one of the pivot points. This would not allow the rod to move to full travel with a load against it. #2 The shift rod between the shifter and bell crank is hitting the floor bracket under the console. I just went thru this with a project car this week. #3 there are incorrect parts installed affecting the geometry. If it still doesn't crank after removing the linkage? Either the weld at the rooster comb inside the trans is partialy cracked allowing slop between the shaft and comb assembly. Or the plastic on the rooster comb is cracked. It is not a neutral switch issue. It makes no difference which way the harness is plugged into the switch. The outer 2 terminals contact together to complete the circuit for the reverse lamps. The center pin grounds to complete the starter relay circuit allowing power to the starter.
Doug
 
When you are experiencing the no start issue go under the car and disconnect the rod from th etrans lever. My bet is the lever will move slightly allowing the engine to crank. If this is the case; #1 The linkage is sloppy at one of the pivot points. This would not allow the rod to move to full travel with a load against it. #2 The shift rod between the shifter and bell crank is hitting the floor bracket under the console. I just went thru this with a project car this week. #3 there are incorrect parts installed affecting the geometry. If it still doesn't crank after removing the linkage? Either the weld at the rooster comb inside the trans is partialy cracked allowing slop between the shaft and comb assembly. Or the plastic on the rooster comb is cracked. It is not a neutral switch issue. It makes no difference which way the harness is plugged into the switch. The outer 2 terminals contact together to complete the circuit for the reverse lamps. The center pin grounds to complete the starter relay circuit allowing power to the starter.
Doug
@dvw I need to clarify: My engine does not crank in P, that's the problem.
#1 There's no slop in the linkage, everything is checked and all parts are new.
#2 As stated before it is a column shift, no floor console brackets to hit.
#3 The rooster comb is the exact same as before. It has no cracks and was in in good shape. The plastic slider on the rooster has been replaced with a new correct one.

Also mentioned before, I have the 1-prong NSS and both of my switches work fine (OE Chrysler NSS). I am aware of the job of the NSS and my backup light switch is on the steering column (bc column shift..).

From what I remember the P start problem wasn't an issue before the restoration. But I don't recall if it maybe was just permanently grounded back then.

Folks..still need advice. Thanks in advance!!
 
Sorry I didn't even look to see if this was an old post. Refeing to your car. What year is it? The rooster comb with a plastic slider is the incorrect part for a single prong switch. It uses a 3 prong switch. The single pin switch fits the rooster comb w/o plastic. Did you install a different switch, comb, or valve body?
Doug
 
Sorry I didn't even look to see if this was an old post. Refeing to your car. What year is it? The rooster comb with a plastic slider is the incorrect part for a single prong switch. It uses a 3 prong switch. The single pin switch fits the rooster comb w/o plastic. Did you install a different switch, comb, or valve body?
Doug
This is great news! I just looked up and when I bought the car it had the 1 prong NSS installed, transmission is a '69. So I should go for the 3 prong NSS. Will try that!
 
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