I've got a MGB GT 4 syncro with o/d.
I went for a drive today doing 60 miles on 4th gear, flicked the switch on the o/d came on fine then switched of a short time after kicking in.
Nothing was happening when I tried to switch it on and of again. Would it be a faulty switch or the a problem with the o/d itself?
Overdrive cutting off
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Remyd
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Overdrive cutting off
Remy Dubois
1971 MGB GT
1971 MGB GT
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Vic Butler
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Re: Overdrive cutting off
First, check the oil level in the gearbox. A low level.csn cause overdrive engagement problems. If that's ok remove the switch and with it switched on, check for battery voltage on both terminals.
If that's ok the next item is the overdrive solenoid which is accessible from underneath the car. It should click when energised.
At least it doesn't stay engaged. Reversing with overdrive engaged destroys the uni directional clutch.
If that's ok the next item is the overdrive solenoid which is accessible from underneath the car. It should click when energised.
At least it doesn't stay engaged. Reversing with overdrive engaged destroys the uni directional clutch.
1977 Stage 2 MGB GT
1975 SWB Series 3 Land Rover with a later 2.5 petrol engine
1975 SWB Series 3 Land Rover with a later 2.5 petrol engine
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Remyd
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Re: Overdrive cutting off
I checked the oil the other day and seems ok, I’ll check the switch next time I’ll be in the garage. Thanks for th info!
Remy Dubois
1971 MGB GT
1971 MGB GT
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Michael Barclay
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Re: Overdrive cutting off
Hi
I had a problem with my overdrive dropping in and out. Turned out to be a corroded bullet connector in the harness below the fuse box. The overdrive wiring is the Yellow and yellow/red wire. Pull the bullets apart and clean with wire wool /emery paper.
Mike Barclay
I had a problem with my overdrive dropping in and out. Turned out to be a corroded bullet connector in the harness below the fuse box. The overdrive wiring is the Yellow and yellow/red wire. Pull the bullets apart and clean with wire wool /emery paper.
Mike Barclay
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Paul Hollingworth
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Re: Overdrive cutting off
Does it come in if you pull the gear stick towards you ? If so then its the inhibitor switch on the gearbox which stops you engaging when in 1st and 2nd. You might have to take out a fibre washer from underneath it. Difficult but do-able. You might have to drop the cross member. Most problems with the overdrive are electrical thankfully.
1971 MGB roadster & 2006 MGTF
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Remyd
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- Joined: Tue Dec 29, 2020 5:54 pm
- Forename: Remy
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Re: Overdrive cutting off
Hi Paul,
I don't know as I only used it in fourth gear but will have to try that if all else fail!
I don't know as I only used it in fourth gear but will have to try that if all else fail!
Paul Hollingworth wrote: ↑Thu Feb 25, 2021 12:30 pm Does it come in if you pull the gear stick towards you ? If so then its the inhibitor switch on the gearbox which stops you engaging when in 1st and 2nd. You might have to take out a fibre washer from underneath it. Difficult but do-able. You might have to drop the cross member. Most problems with the overdrive are electrical thankfully.
Remy Dubois
1971 MGB GT
1971 MGB GT