Jump to content

non cranking??


Twinpilot001

Recommended Posts

my 1982 datsun 720 4 x 4  -i just  started the engine after a rebuild- ran good a few mins. Now it will not crank. Replaced starter & battery-all new!! still no crank. What's up here? I seem to have a relay on the fusebox that clicks when i turn the key to start-yet wont crank! This is an original z22 engine & truck-no electrical was messed with-all original I also have replaced the key switch with a new one. Help..

Link to comment
  • Replies 6
  • Created
  • Last Reply

Top Posters In This Topic

Top Posters In This Topic

Too many parts have been thrown at this problem. Now you don't know if the new battery, starter or the ignition switch is good or not. You may have added another problem. Throwing parts at it is always the expensive way to fix things.

 

 

Turn on the headlights on high beam. Sound the horn. Lights nice and bright? Horn sound normal?... Assume the new battery is ok and charged up.

 

Place in neutral. Pull Brown/Red starter wire off solenoid. Use a wrench to short across the + battery cable to the solenoid lug. If starter cranks we can assume it's fine.

 

Get a $5 test lamp or a meter. Pull the Brown/Red start wire off the solenoid and test for voltage when key is turned to the START position. Should be near battery voltage. If yes, ignition switch is probably ok.

 

 

So why no work? Well there is one more thing. Check the ground wire from the battery where it bolts to the intake near the thermostat. Clean and tight? It was off for the rebuild....

Link to comment

Maybe i didnt explain myself as i should have ??Old starter on car had a frozen bendix drive- no drive available so -new starter!!  Key switch was worn out-so new key switch installed. Didnt have a battery so i got a new one.  Napa new starter=didn't even work 1 time= -i removed & returned to store - checked good. yes I checked the solenoid  wire-black one with red stripe- heres whats  interesting?? when key switch is  turned to start- power is going thru that wire-YET!! isn't  like full 12v power-seems weak (test light) --no i didn't check voltage with a proper meter yet-i will today -my concern is this= I hear some sort of solenoid making contact when the key is turned to start-NOT the starter solenoid. This one is  on/near the drivers side panel /fuse box area. What is that & what does it power?other than the solenoid (starter) also whats this thing called an "inhibitor relay" never herd of this term till i get the datsun. whats that do? been a certified mechanic 50 years now and as we all know - still learning about parts  from diff auto mfg's that are termed differently. seems that  relay by the fuse area is not delivering a full 12v to the starter?? Ill also ask where is the relay?? that powers the elect fuel pump located?Thanx to all!!

Link to comment

Inhibit relay is for automatics (start only in N and P), as you have a 4x4, and they never came with one, I skipped over that.

 

Weak 12 volts to the starter solenoid is common on old Datsuns. My 710 was this way. Only 6 or 7 volts getting through. Small thin wire and voltage has to travel about 15? feet from battery to switch and back to solenoid... there will be losses. Try a meter to confirm the voltage is low. Try plugging in the ignition switch plug several times to make a clean contact. Jumper 12 volts directly from the battery to the solenoid... if it cranks normally, that's the problem.  My cure was a 'hot start relay'.. using the 6 volts to energize a small relay directly from the battery.

Link to comment
  • 3 weeks later...

Was the OPs problem ever solved? this is exactly what mine is doing right down to the clicking relay under the dash and nothing else.  I will be checking the connections and voltage today as well as the cranking amps of the battery which is where I think the issue lies..battery shows 12volts with the meter but i have a feeling that under load its not producing the required AMPs  ..this will be the third battery in 6 months that I have replaced with its issue...and the kicker is they were all indifferent cars...my wifes Murano, and my other daily.. weird that they would all crap out at the same time but weirder crap has happened i guess.

 

And I plan on  doing the hot start relay very soon regardless..

Link to comment

I will try a remote  starter switch today. I have  load tested the battery & checked it even with a hydrometer. all good.-What is confusing to me is  under the drivers side  dash area =( fuse panel-im guessing?)  i can hear  a clicking when key is turned to start /crank. Yet  im informed there is NO relay in wiring system?  So now ill measure voltage @ the start circuit @ key switch & @ starter solenoid terminal !!  Not even a corroded wire in the trucks system!! even new battery cables!! Likely I'll need a relay in the system !!

Link to comment

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.