Overdrive behaving badly

[Freebird]

Hi

After a prolonged thrash to, round and back from Spa the OD decided to play up this morning having been as good as gold all weekend.

At first I thought it was one of the usual electrical maladies, but somehow I don't tink it is. What was happening was the OD would drop out if given any gas at all, back off and it would come in again but as soon as I touched the accelerator it dropped out almost as if is had kick down.

A bit later in the journey to work it behaved normally and a bit aler still it wasn't coming in at all.

Pick the bones out of that!

[andy thompson]

Sounds sick - clean all filters if possible but expect internal maladies - overdrive spares in Rugby rebuilt mine - total experts and not to expensive (300 quid for a fully rebuilt competition spec J Type)

[Nick Jones]

Could still be electrical - the engine and box will move around under torque reaction and are possibly leaning on wiring somewhere?  Power on/off will also move the gear selection mechanism slightly which could have this effect if the inhibitor switch adjustment is marginal.  Might be able to replicate the last one by wiggling the gear lever?

Nick

[Freebird]

Nick_Jones wrote:

Could still be electrical - the engine and box will move around under torque reaction and are possibly leaning on wiring somewhere?  Power on/off will also move the gear selection mechanism slightly which could have this effect if the inhibitor switch adjustment is marginal.  Might be able to replicate the last one by wiggling the gear lever?

Nick

OK, will try things on my way home tonight. What syptoms does low oil level give?

Box is coming out soon anyway as need a new clutch, so no problem deliving into it then.

Glen.

[Jason]

The last three overdrive issues I've had (all on different cars) have all been electrical and pretty similar to your symptoms, one was in the gearstick (silly place to put an overdrive switch) teh other two were electrical connections to the solenoid - both were caused by hot oily wires going brittle and failing in the hostile environment. All 10 minute jobs to find and fix. Electrical is your fist set of test as they are easy to apply and usually cheap to fix :-)

[mazfg]

I've just sorted out my overdrive fault and twas electrical. Found it very intermittent, sometime it would work from cold, but as the engine warmed up it stopped working. I could hear the relay by the battery clicking, as well as the solenoid, but wouldn't behave.
I took the relay off and apart..found a bit of rust n iron filings around the magnet and corroded contacts. Cleaned up, re-sealed with some silicon and replaced. Now working 1st time and every time

[andy thompson]

Maybe because I've actually broken two overdrives recently I'm moving away from the electrical solution optimism frame of mind - everyone is of course correct  8)- check all electrical possibilities (and oil level) before getting ready for gearbox removal LOL (gangsta)(scared)

[Pete Lewis]

having low  gearbox oil level will drop out on load
as said check inhibitor switch and gear lever wiring,if in dobt connect a small test bulb to the solenoid feed and if its out when its in you have a elec defect.

gear lever wired switches are notorious for fractured wiring.

Pete

[Freebird]

Thanks for everyones help. It was faultless on the way home last night  :-/ Switch is on the column, not the gearlever.

Now laid up for head gasket, clutch and gearbox bearing replacement before ventruing to the 'ring early July. I will check all the wiring an obvously replace the oil at the same time.  :)

Thanks again

glen.