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Overdrive problem

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bighealeysource

bighealeysource

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Hey all,
Thought I had my overdrive issues all worked out. Thoroughly
tested the OD relay and throttle switch,got a nice click from
the solenoid when ignition on, OD switch on dash toggled to
OD and you bump the gear lever to 3rd or 4th. Took it out
for a test drive, flipped it to overdrive and engaged
perfectly. Disengaged when toggled off, reengaged, worked
fine. Apparently all the solenoid activity blew the 5 amp
fuse between C1 post of OD relay and the isolator switch but simply went to the 10 amp as some had advised. Put the fuse in
to isolate the OD harness so it couldn't burn up again !
Now, ignition on, bump the gear lever to 3rd or 4th and get
the very definitive click but on the road, it does not
engage. The solenoid appears to be working so am I looking
at a solenoid adjustment maybe ? Some pretty bumpy roads
around here, maybe the adjustment got knocked off a bit?
Any ideas or recommendations would be appreciated. Looks like
I am going to have to pull the trans cover - ugh.
Thanks,
Mike
 
Apparently all the solenoid activity blew the 5 amp
fuse between C1 post of OD relay and the isolator switch.

Yes if you did not use a 5 amp "slow blow" it could blow under these circumstances.



/ but simply went to the 10 amp as some had advised. Put the fuse in
to isolate the OD harness so it couldn't burn up again !
Now, ignition on, bump the gear lever to 3rd or 4th and get
the very definitive click.

but on the road, it does not
engage. The solenoid appears to be working so am I looking
at a solenoid adjustment maybe ? Some pretty bumpy roads
around here, maybe the adjustment got knocked off a bit?
Any ideas or recommendations would be appreciated. Looks like
I am going to have to pull the trans cover.

Probably so, but You might get lucky and only have to readjust the Overdrive gear switch, it may not ride the anvil correctly under normal driving position of the gear lever.----Fwiw--Keoke
 
Hey Keoke,
Thanks for your advice. Are you referring to the Throttle switch on the firewall or the isolator switch on the tanny ?
Thanks,
Mike
 
I *think* he means the one on the side of the transmission. I had to play with a few different washers (thickness varies) to get mine to work consistantly.

Back in the day, with enough wear on the gearlver and bush, you could momentarily disengage the overdrive by pulling the lever towards you (LHD car) to get a kick-down, or passing gear. Accelerate past the slower vehicle and release your hold on the lever to resume overdrive-top.

I recently (this past February) reverted back to an overdrive xmsn, and had to fiddle with the linkage a bit too. It's a very fine-line between no overdrive, overdrive pull-in (HIGH current draw) and a correctly adjusted solenoid.

Patience is key, as are tiny increments of adjustment.
 
:savewave:
the isolator switch on the tanny :yesnod:

----------------------------Keoke
 
bighealeysource said:
Hey all,
Thought I had my overdrive issues all worked out. Thoroughly
tested the OD relay and throttle switch,got a nice click from
the solenoid when ignition on, OD switch on dash toggled to
OD and you bump the gear lever to 3rd or 4th. Took it out
for a test drive, flipped it to overdrive and engaged
perfectly. Disengaged when toggled off, reengaged, worked
fine. Apparently all the solenoid activity blew the 5 amp
fuse between C1 post of OD relay and the isolator switch but simply went to the 10 amp as some had advised. Put the fuse in
to isolate the OD harness so it couldn't burn up again !
Now, ignition on, bump the gear lever to 3rd or 4th and get
the very definitive click but on the road, it does not
engage. The solenoid appears to be working so am I looking
at a solenoid adjustment maybe ? Some pretty bumpy roads
around here, maybe the adjustment got knocked off a bit?
Any ideas or recommendations would be appreciated. Looks like
I am going to have to pull the trans cover - ugh.
Thanks,
Mike
Click to expand...
I had a solenoid that worked like yours does statically but didn't engage while driving. Turned out to be a "weak: solenoid. Changed solnoid and problem was fixed.
Patrick
 
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