1G Intermittent no crank

[willyp42]

Hey Everyone,
looking for ideas.
right now i have the clutch position switch un plugged and the starter relay jumped i am getting an intermittent no crank
when i probe all pins at the relay during crank, I am seeing battery voltage at one of the vertical pins (3 i think) but none anywhere else.
shouldnt i be seeing a voltage at pin 2 also?

i know the starter isnt bad because if i jump the top connector of starter to battery it cranks every time.
thanks,
-Will

 

[1990TSIAWDTALON]

The contacts on our 30 year old relays may be shot Will. I would suggest trying another relay in that spot just to see if it continues or goes away.
Marty

 

[willyp42]

The contacts on our 30 year old relays may be shot Will. I would suggest trying another relay in that spot just to see if it continues or goes away.
Marty

i have a wire across pins 3 and 4 right now and its behaving the same,
but do you know where to get one? i seen one on performance part part out but none seem to exist in new form.
-Will

 

[shellhouse]

With the starter relay jumped, does the solenoid engage but not crank? There should be a click/thud for the solenoid. If it's engaging then the starter needs to be disassembled and internal contacts cleaned for the solenoid.

After the gear pushes forward to engage flywheel, there are contacts which power the starter motor to turn it over. Those contacts degrade and oxidize due to arcing over time.

 

[willyp42]

With the starter relay jumped, does the solenoid engage but not crank? There should be a click/thud for the solenoid. If it's engaging then the starter needs to be disassembled and internal contacts cleaned for the solenoid.

After the gear pushes forward to engage flywheel, there are contacts which power the starter motor to turn it over. Those contacts degrade and oxidize due to arcing over time.

yes it click/thuds every time.
ive also put a spade connector on the solenoid and jumped it to the battery and it cranks every time. which leads me to believe its some kind of power delivery problem.

 

[shellhouse]

Sounds like it may be getting just enough of a stronger engagement to those contacts with hotwire, but I'd still suspect the contacts since it sounds like the solenoid is working with the other wiring.

 

[1990TSIAWDTALON]

To clarify, the starter BRUSHES are possibly wearing out, maybe down to nothing. They hide out right behind the end plate. You have to remove 2 long, small bolts to get it apart.
If it starts every time you jump the signal wire, then test the VOLTAGE at the signal wire when you use the key. I think you will find a drop in voltage, but then will need to run down why or use a typical 4 terminal relay to do the job, much like in a fuel pump rewire, using the old signal wire to engage the relay to send a full 12v to the spade terminal on the starter.
We used to be able to buy new starter drives, brushes and end bushings but I haven't seen them, even for domestic stuff, in quite a while.
I think your starter relay is ok, its not getting a strong enough signal voltage.
Let us know what you find.