Overdrive Problems

[bucaneer]

My overdrive stopped working. I changed the solenoid, did not help. The dash switch quit after installing the solenoid. What do I try next?

 

[Keoke]

Sounds like a switch failure. Try a new switch

 

[bucaneer]

Thanks for the suggestion. I failed to mention that the car is a 67 3000.I removed the switch and the insulation was melted on the leads into the switch.Is this a switch problem or a sign of something else?

 

[Patrick67BJ8]

Thanks for the suggestion. I failed to mention that the car is a 67 3000.I removed the switch and the insulation was melted on the leads into the switch.Is this a switch problem or a sign of something else?

The OD circuit isn't fuse protected. I burnt my OD harness, plus part of the main harness several years ago. I never did find out what caused it because I swapped all the relays, tc.,parts from a parts car to it. I suspected the throttle switch or relay shorted out internally. You can try and disconnect the throttle switch and relay on the firewall and troubleshoot from there. I actually left my throttle switch disconnected for several years with no problems.

 

[57_BN4]

Test the solenoid coil resistance, it should change from about 0.4 ohm when the lever is down to ~11 ohm when the lever is manually pulled up to the engage position. If you don't see the resistance change as the lever is pulled up then either the lever is not adjusted correctly or the solenoid coil has burned out/shorted internally, or quite likely both if it has been driven any distance with the lever incorrectly adjusted.

There are many websites detailing how to adjust the solenoid lever correctly, it is a very common problem.

Andy.

 

[TimK]

My solenoid failed. I replaced it but used the original plunger. I put a 10 amp fuse in and blew it the first time i engaged the OD. The old plunger was not long enough to reach the button at the top of the solenoid cylinder to push the button that switches off the high amp pull-up circuit to the low amp hold circuit. I then installed the new plunger that came with the new solenoid and everything worked fine. It was longer than the old one. I think everyone should have the solenoid circuit fused. I did follow the adjustment procedures in the manual.

 

[bucaneer]

I replaced all the overdrive electrial componets. the first time I cut on the switch I heard the solenoid click. when I attempted to start the engine for a test drive,while cranking the engine every thing elctrial died. The stater stopped and I have no wipers, turn signals,brake lights and fuel pump does not click. I have head lights, parking lights and horn. All was workig just before the attempt to start.Where do I start?

 

[Richard Dickinson]

Sounds like you have blown the 35 amp fuse A3-A4. Disconnect the solenoid,replace the fuse and work back from there.

 

[bucaneer]

All electrics are back on line and overdrive appears to be working. What range of rpms should the engine run in 4th in overdrive. Thanks to everyone for the help.

 

[TimK]

You can run to red line in OD. (5300 rpm)

 

[bucaneer]

When the overdrive is engaged how many rpms shuld the engine drop. If I am running 4,00o rpms and engage the overdrive how many rpms should I now be running.

 

[Bob_Spidell]

If you're running steady at 4,000 RPM and throw the switch the drop should be roughly equivalent to the O/D's rating (either 28% for early cars or 22%--880 RPM--for later 6-cyl cars). If you're accelerating you'll get a speed increase but little/momentary or no RPM drop.

 

[bucaneer]

TimK,how did you fuse your solenoid circut? where,how and 10 amp fuse?

 

[TimK]

I fused the solenoid circuit with an in-line fuse available at auto parts stores. You can select any amp fuse. I selected a 10 amp fuse based on advice from Keoke. It will blow if the pull circuit remains on for more than a few miliseconds. The hold circuit is less than 2 amps. All the other fusing shown in the photo I did later to put everything on fuses.

I got the fuse block from J.C. Whitney. Not elegant, but it works. Allows separate fusing for circuits that are controlled by ignition switch (like fuel pump) and those that are not, like lights.

 

[bucaneer]

Thanks for the help.

 

[richberman]

buc,
Charlie Hart sells a fuse block which fits directly onto an unaltered Healey. If you PM me I can send you his email address. It's a $60 mod. Info is available at John Sim's Healey6.com technical pages.

rich

 

[Patrick67BJ8]

buc,
Charlie Hart sells a fuse block which fits directly onto an unaltered Healey. If you PM me I can send you his email address. It's a $60 mod. Info is available at John Sim's Healey6.com technical pages.

rich

These do not fit the BJ8's as the green wires are on the opposite side. I took Charlies fuseblock and made it work. I have to sort out all the pics I have but if someone needs to see pics they can send me a PM. I also have removed the OD system since I have a 5-speed, but there appears to be enough clearance for the OD stuff. I did have to move the oil line down & out a little bit to clear the main wiring harness but easily returned to original. Charlie is going to see about a fuseblock dedicated to BJ8's.