Neutral Safety Switch

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Travco Model: 1976 270

Neutral Safety Switch

Unread post by RobC » Tue Jun 30, 2015 4:28 pm

Lo and behold after sitting for a few months I was not getting any juice to the starter as of yesterday. I am getting ready to fire up my beast with the rebuilt TQ on top but not go.\n\nIt will crank in Neutral but not in Park. Sounds like the Neutral safety switch should be making contact on both the Neutral and Park position.\n\nI am hoping it is just the switch and not the linkage inside.\n\nAnybody experienced this?\n\nRobC\n\nPS Manual says pull the plug and inspect to make sure the contacts are centered on the hole in Park and Neutral. My tranny is going to get rebuilt here pretty soon but I sure would like to know why no Park starting.

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Travco Model: 1975 270,1974 220
Location: North East Ct

Re: Neutral Safety Switch

Unread post by Acesneights » Wed Jul 01, 2015 3:50 pm

Let us know, I have never personally messed with it. It might be on the shifter ???
1977 Travco 270 Elite\n1974 Travco 220 Parts unit

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Travco Model: 1976 270

Re: Neutral Safety Switch

Unread post by RobC » Wed Jul 01, 2015 5:22 pm

Figured it out.\n\nThere are two mechanical contact points inside the transmission attached to the shifter lever mechanism. When in Park or Neutral the contact points touch the center pin on the neutral safety switch grounding it to the transmission case and completing the circuit to the starter relay and allowing the starter relay to do its job. \n\n"Full power to the starter Scotty"\n\nIn any other position R D 1, 2 or 3 there is no contact, no ground and no go.\n\n"I'm givin it all she's got Captain... ya can't change the laws of physics...."\n\nThe switch only completes the circuit to the starter relay so you can shift all you want while its running.\n\nThe fix was to clean all the dirt and oil and crap off the selector lever area on the drivers side of the tranny. It was pretty gnarly down there (**** with Simple green, toothbrush and follow with some carb cleaner). I then "aggressively" put the beast into and out of park a few times. the Park position is all the way back on the tranny lever and It was probably just not quite getting there (see **** procedure above).\n\nProblem solved. Bottom line is that the selector lever pin and seal are probably worn out and a rebuild will fix that but for now I am mobile.\n\nTwo birds with one stone: I have a tranny fluid leak somewhere down there in that area. Enough to drip a few times a day onto the exhaust pipe which upon start and warm up makes for a very dramatic smoke show for about 5 minutes in the driveway. The leak is one of the following:\n1) forward oil cooler line fitting\n2) Kickdown adjustment bolt\n3) Selector switch pin seal or kickdown pin seal\n\nNow that is all hospital clean down there I may be able to actually see where the oil is coming out.\n\nStay tuned.\n\nRobC

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