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aleda

Overdrive not working?

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Hi all - had Betty out this week and don't think the overdrive is working. Just been along the A414 at 50 plus in 4th gear and the rev counter at 2500 and couldn't see that the overdrive kicked in. I thought it was playing up the other day and kept trying it, then it did kick in. Is there anything obvious (driver error!) to look for? It has recently been renewed.

 

Also AJ very kindly gave me the AA Book of the Car and I want to ensure I am carrying the right tools in the boot - just been sorting through spanners in the Garage, open-ended, ring, screwdrivers, wow, where do I start. Do I really need to carry the starting handle? Am probably not strong enough to use it anyway. Is it worth carrying a socket set? Hmmmm - advices always very much appreciated.

 

She's driving like a dream by the way, could go to the end of the world :) and not come back.

 

Cheers

Christine Essex

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Christine

 

If you can establish that the overdrive (solenoid) is clicking in, check the gearbox oil level (shared with the o/d unit). a low level will cause symptoms you describe... Ask me how I know! :rolleyes:

 

Good luck with it!

 

Cheers

 

Ian

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Hi Christine,

as Ian says check that the solenoid is engaging.

Select 4th gear.

Turn Ignition ON but don't start the motor,

Whilst carefully listening flick the O/D switch (and look at the ammeter) - did you hear a click (clunk) or did you see the ammeter flick towarads a discharge.

If you did then the solenoid is engaging - this is good.

If you didn't then there is probably a fault in the wiring.

 

Again as Ian says - check the oil level (in fact change it). Drain the gearbox. You can examine it for any significant debris.

Replace with the oil of your choice - I prefer the thinner oils SAE40 gearbox oil etc Penrite do a good one.

 

Test run - drive at a steady 60MPH this should give 3000RPM with the standrad diff.

Whilst looking at the tacho (watch out for the pedestrians) engage O/D. You should hear/feel the engine change tune. The tacho should drop to apprx 2500RPM.

 

Best of luck

Roger

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Christine

If the solenoid is clicking in and out OK I would check early on that the lever clamp at the solenoid side has not moved since being set recently. There is a rigging pin hole on the other side of the OD unit which should take a 3/16 pin (usually a drill shank)when the solenoid is engaged. I have had this clamp move several times, albeit I beleived it was tight, before I managed to fix the issue with a replacement lever.

If you had the OD renewed locally take it back to them and ask them to check this for you, as it very difficult to check this without either removing the gbox tunnel or having the car in the air.

 

All the best

 

Rog

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Hmm - just did as you suggest, no tick, no ammeter drop. Had gearbox overhauled and overdrive rebuilt in January so guess its electrics as gearbox oil would have been done then? Methinks I will have to get her back to Carlow, I have to book her in for the rewire anyway. Thanks as always for your advices, I was hoping that maybe it was something simple, never mind.

 

Just washed her and she does look grand.

 

Cheers everyone

 

Christine Essex

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Christine

 

It's an electrical problem so could be fairly simple to diagnose. There are a few simple checks you can do starting with the overdrive relay. The relay is probably mounted (inside car) on the driver side bulkhead just above the gearbox tunnel or thereabouts. Assuming you've got the original type relay, there are 4 terminals marked C1, C2, W1 and W2. First connect a 12v bulb between C1 and earth. Turn on the ignition, if the bulb lights then the power supply is good, if not, then the electrical supply upstream of the relay is the problem - check fuse or connection on fusebox. Assuming the first check is ok, next check is to do the same test between terminal W1 and earth but this time with the o/d switch on. If the bulb lights the power supply from the overdrive switch is good, if not check the connection at the switch and/or power supply to the switch. If C1 and W1 both have power, connect the bulb between C2 and earth and turn on the ignition & o/d switch, if the bulb lights the solenoid is probably faulty, if not the relay has failed and a replacement should fix your problem. Final check is to test the relay earth, connect your 12v bulb between a live supply (e.g. battery terminal) and W2 on the relay and select 2nd, 3rd or 4th gear. If the bulb lights the earth is good, if not the earth connection to the relay is the fault.

 

Good luck

 

Bill

Edited by badshead

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Christine

It is the best news you could have had in the circustances. ( You did have it in gear (2,3 or 4)for the test as advised by Roger?) A bit of wire, or at worst a new solenoid and you should be back on the road and cruising.

Sounds a simple fix.

Best of Luck

Rog

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Yes Rog, I did have it in 4th gear as Roger recommended so I think the test result is sound. Am going to a little local car show next Saturday, think I will print off Bills post, take my workshop manual, probably won't fix it but at least read it through to try and understand it. There will be some other classics (and vintage) there and probably someone to show me round the sections Bill talks about. I need to get on a car mechanics course but guess they no longer exist!

 

Thank you everyone

 

Christine

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Hi All

Hope you solve your problem Christine some good advice given

Just wondered if they have come across a problem of no hydraulic pressure. Electrics are ok.

someone who is just about had enough problems with his car (paul)

Thanks

Mark

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