Sticking starter

[Slant6Dude]

I have a 68 D-100, factory Slant 6 converted to 318. It still has the three speed collumn shift and direct drive starter.

Any time I crank the starter motor for more than a few seconds without starting the motor it sticks. Supose I am doing a compression test or the truck is cold and the motor doesn't start right away. When I let go of the key the starter keeps right on turning the motor until I disconect the battery. If the engine starts I assume that the speed of the flywheel gives the bendix an estra shove and the starter disconnects. This has happened with two different starters. The battery is new and the starter relay is about a year or so old.

Any ideas?

Thanks in advance
Slant 6 Dude

[Jeffc]

I think you have a bad ingition switch, but could be
relay also.
Test 1
If you jump at the relay does the starter act normal
and disengage right away? if you haven't tried that
give it a shot. Take a screw driver and cross
from were battery cable is on relay to red wire
post on relay.
If it does then it most likely that switch is not
shutting off the power to relay, but try 2nd test.
Test 2
To test the relay to see if it passing juice right,
take a hot lead from the battery and feed it to
the relay post that has the "orange wire", should kick the starter and starter should stop when hot wire is removed.
Test 3
To test ing. switch, Pull orange wire off the
relay, have a helper turn key to "start" and hold, test orange wire to see if juice is passing,
and if it stops when switch is moved to run.
If juice does not switch off when in run, you
switch is bad.(12v light tester or volt oms meter)

[Jeffc]

Thought I should add, if in the frist 2 test
if the starter stays on, the bendix is sticking
on and that is the problem.

[wideblock]

sounds like a sticky soleniod at the starter or a sticky relay. id do like jeff said and jumper past the relay and see if it sticks any. cant rely on the age of now days cheap made parts, i went thru 3 relays on my 66 in 2 years before i got a good one.

[Veriwide]

I just replaced the starter solenoid in my 71 Adventurer today. The post where the positive battery connects was loose, then fused in place when it shorted and melted the negative battery cable terminal. The part was @$35.00 with tax, and an easy fix, well it was easy for me as my truck has a 4 inch lift.