Driving with Overdrive

[Chix]

Hello team! Well I fixed the electrics to my A-Type overdrive and it worked for a bit.

Now however, I can hear the solenoid flick in when in gear with the engine stopped and ignition on, but with engine running, it doesn't engage (obvs driving while in 3rd/ 4th).

Just topped up the gearbox oil, and hasn't immediately fixed it. Any ideas?

Also, when it is working, how does one drive with it? Just flick it on and off? Take foot off the gas while flicking? Dip clutch?

There's a bit of a jolt when mine disengages...

Cheers

Chix

[Lingen]

Chix.. There is no need to dip the clutch. When accelerating just switch it "In". A bit of a jolt is normal. When switching it out, the jolt can be reduced if the engine is not on the "Overrun".
Mike.

[JJF]

Dip the clutch for me, good habit, always in control and no issues under braking.
Appreciate each to their own.

[flying farmer]

Might be the points in the cap of the solenoid. They are similar to contact breaker points.

The A type has a high ampage pull in coil and a low ampage holding coil once it is engaged. The contacts are pushed apart when the solenoid has reached full travel, if they are not passing full current the solenoid will not pull in far enough to engage the overdrive.

This used to irritate me a couple of times a year when I had my old PI saloon with an A type, it would be fine in the dry summer weather but would need the points cleaning with some 1200 grit wet and dry a couple of times during the Winter.

Another option is the overdrive relay playing up which would leave the pul in coil without current

A type overdrives do tend to be a fair bit sharper on both engagement and disengagement compared to the J type

[trunt]

It’s been a long time since I had an A type but ISTR an adjustment of the solenoid to ensure that the OD Is fully engaged when the solenoid was fully activated, it involved lining up a hole in the arm with a hole in the casing and adjusting the solenoid.
Not sure if the stag is the same but I suspect it is
Terry

this may explain..

https://m.youtube.com/watch?v=gV_Kjtyhy8k&t=24

[Alacrity]

If you can hear the solenoid clicking when you switch it in then forget about the electrics, they are working fine. Be carefull when setting up the arm movement with the ROM, mine wouldn't disengage when set according to the book.


No need to use the clutch when going in or out of O/D, it is designed to work with the power on as an auto would. When overtaking in 3rd switching the overdrive in when the revs come up makes for great acceleration past. I love it!

[DJT]

No need to use the clutch when going in or out of O/D, it is designed to work with the power on as an auto would. When overtaking in 3rd switching the overdrive in when the revs come up makes for great acceleration past. I love it!

That is how I drove mine for over 60,000 miles, and it wasn’t treated gently either……

[LAMBRETTLAD]

If you can hear the solenoid clicking when you switch it in then forget about the electrics, they are working fine. Be carefull when setting up the arm movement with the ROM, mine wouldn't disengage when set according to the book.


No need to use the clutch when going in or out of O/D, it is designed to work with the power on as an auto would. When overtaking in 3rd switching the overdrive in when the revs come up makes for great acceleration past. I love it!

Best to dip the clutch when coming out of overdrive ,to protect your cones .I think

[Alacrity]

Best to dip the clutch when coming out of overdrive ,to protect your cones .I think

No need, it is designed to work independently from the clutch.

[trunt]

Best to dip the clutch when coming out of overdrive ,to protect your cones .I think

So wear the clutch out instead?

OK so seriously, yes, I have been known to do that for a clunky disengagement but recently realised that any slack in the drivetrain will amplify any clunkiness on disengagement and with a nice tight drivechain its much smoother.. so basically if it feels too bad then drop the clutch for your sanity but it’s not really required.

Terry

[Chix]

Thanks everyone, a good varied spread of opinion!

[Chix]

Here are the latest symptoms, if anyone can help me diagnose, I’d be very grapefruit!

after a couple of days of sitting there, I turn the ignition on, put in third, switch on and I hear the click. Switch off, switch on again, hear the click. Same in forth.

Then I start the engine. Put in third, switch on, still hear the click. Same in fourth.

Then I engage first gear, drive out of the garage, stop. Engine is still running, put in 3rd gear and switch on, no click! Then drive around, overdrive doesn’t engage.

Then put car away. Couple of days later, it works again, but stops when I start driving around.

What is going on??

Thanks team

[Lingen]

Chix.
I would go back to Flying Farmer's suggestion that the contacts in the back of the solenoid behind the black plastic cover, need cleaning.
Mike

[trunt]

Can’t think of anything obvious but most intermittents are down to electrics, so to establish whether this is electrical or mechanical connect a bulb across the solenoid which will light when it has power. Drive around and observe it.. It should always light when the switch is engaged, if not then you have an electrical problem before the solenoid

[Alacrity]

OK so seriously, yes, I have been known to do that for a clunky disengagement but recently realised that any slack in the drivetrain will amplify any clunkiness on disengagement and with a nice tight drivechain its much smoother.. so basically if it feels too bad then drop the clutch for your sanity but it’s not really required.

Terry

If you get a bump in disengagement then instead of disengaging with the throttle closed the simplest thing is to either disengage as you lift off or keep the throttle open a little whilst doing so. Using the clutch is just pointless.