400 engine sometimes doesn't crank

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Jun 7, 2016 | 03:54 PM

Matt1966

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Tuned

Joined: Apr 2013

Posts: 498

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From: Sweden

400 engine sometimes doesn't crank

Hi! Can you please help me out here! Sometimes the Engine doesn't crank.
Battery and wiring between Battery/Starter relay and starter was new last fall and everything was fine then. Now, once in a while nothing happens.
I am thinking of buying a new Starter Relay and then maybe jump wire the Neutral Safety Switch. Could it be bad ground to the Engine and Starter or a bad Ignition switch? I dont know where to start?
What's the best way to start troubleshooting here?

Jun 7, 2016 | 04:11 PM

greentruck72

Elder User

Joined: Feb 2015

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From: south east kansas

my 72 had that problem turned out the solenoid wasn't bolted down to the fender all the way.

Jun 7, 2016 | 04:29 PM

DB429SCJ

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Joined: Apr 2016

Posts: 858

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From: Buffalo NY

Check the 90 degree push-on connectors at the starter relay,these are famous for losing contact. Make sure the relay has a good ground to the fender. When you have a no-crank condition, hold the key on the start position and move the shift lever to different positions,the shift linkage may need adjustment. DO NOT jump the neutral safety switch,that can be dangerous.

Jun 7, 2016 | 05:37 PM

Matt1966

Thread Starter

Tuned

Joined: Apr 2013

Posts: 498

Likes: 53

From: Sweden

Thanks a lot! I will check the ground and change the push-on connector for the Starter relay/solenoid tomorrow.
If the Neutral Safety Switch and Starter Relay are okey but the Starter is bad is it then possible to here a "click" sound from the Starter Relay.

Jun 9, 2016 | 05:31 AM

DB429SCJ

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Joined: Apr 2016

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From: Buffalo NY

Yes; if the relay clicks and the starter doesn't turn , the starter could be bad. Make sure the negative cable from the battery to engine is good.

Jun 9, 2016 | 06:11 AM

Matt1966

Thread Starter

Tuned

Joined: Apr 2013

Posts: 498

Likes: 53

From: Sweden

I am still working with the failure but 9 times by 10 it cranks just fine which makes troubleshooting a little difficult. Yesterday I checked
ground for Starter Relay and changed the push-on connectors. I also checked all wiring between Battery-Starter Relay- Starter and all ground Cables.
Now I just have to wait until it dont crank. I think failure is Starter Relay or Neutral Saftey Switch because I dont think the Relay clicks when this happens. Is it possible to adjust the position for the Neutral Safety Switch if it's not broken or do I have to adjust the Shift Linkage?
Thanks a lot for suggestions and input!!!!

Jun 11, 2016 | 10:21 AM

DB429SCJ

Laughing Gas

Joined: Apr 2016

Posts: 858

Likes: 118

From: Buffalo NY

Try this; when you get a no-crank , hold the key on start and move the shift lever. Push it up into the park position then move it down into neutral.If it cranks, shift linkage needs adjustment. Neutral switch may be adjustable.73/77 the switch is on the steering column under the dash, adjustment is easy. 78/79 it is mounted on the transmission. It has some adjustment but be careful,it is mounted to the trans with 2 small bolts that break off very easily. Adjusting linkage would be easier. What year is your truck? eng/trans 2or4wd.