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Overdrive indicator
- Thread starter Tabcon
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TR4nut
Yoda
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I thought the number is normally pretty close to the engine/commission number but might be wrong on that. But there are other tell-tale signs too - for instance the metal plate on the top of your cover near the switches is not a TR4 item, but I think it is for a TR6. Likewise the side position of the reverse switch, TR4s didn't have them at all. TR6 transmissions also had thicker bellhousing flanges, which isn't a bad thing.
TR3driver
Great Pumpkin - R.I.P
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The gearbox serial number should have a prefix to indicate what car it's from. TR4/A would be CT I believe, while TR5/250/6 had several different prefixes like CD, CF, CP.Tabcon said:
The OD also has a S/N that can be used in a similar fashion.
But in both cases, it really only indicates where that part came from. Many of the parts interchange, so someone like John E. may well have built yours from a collection of parts from different cars.
My TR3A had a mid or late TR6 box with early TR6 gears, a TR3 top cover, and a TR4 OD.
TR4nut
Yoda
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TR3driver said:
Yep, they are listed as an option in the factory catalog - but I always thought they were a dealer add-on, but might be wrong on that. However, I don't think the switch would have been side-mounted like on the top Tab has, it would have been on one of the bosses on top of the cover.
Randy
Moseso
Jedi Knight
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Looks like an "A" type, with no solenoid in the hole, to me.
Easy OD ID:
Look on the bottom --
A type: BIG brass hex cap for oil drain -- also solenoid mounts vertically on left side.
J type: Plate held by multiple small bolts for oil drain -- solenoid mounts horizontally, fore-and-aft on left side.
Sorry, no pictures handy...
Easy OD ID:
Look on the bottom --
A type: BIG brass hex cap for oil drain -- also solenoid mounts vertically on left side.
J type: Plate held by multiple small bolts for oil drain -- solenoid mounts horizontally, fore-and-aft on left side.
Sorry, no pictures handy...
TR3driver
Great Pumpkin - R.I.P
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Yup.Moseso said:
I expect John recommends that the gearbox & OD be installed in the car without the solenoid, and then the solenoid installed afterwards, to reduce chances of damaging the solenoid during installation. There is brittle plastic inside that rubber boot on top (that houses the pull-in contacts) and it's easily broken if it gets bumped. The rubber boot tends to hide the damage; I'll bet John has even gotten a fair number of "It doesn't work" calls because someone didn't notice that the solenoid was damaged.
BTW, not all A-types have the solenoid mounted vertically.
https://www.triumphstag.net/start/technical/partslist/images/04-12.gif
TR4nut
Yoda
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Hmm, looks maybe it was brought over from the UK or Australia perhaps? Listed as from a 2.5 PI tranny:
Club Triumph Info
Club Triumph Info
bgbassplyr
Darth Vader
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Oh Boy! A restoration of misc. parts.
Here a piece, there a piece, everywhere a box of pieces. EIEIO.
It's a joke. No offense.
Jim
Here a piece, there a piece, everywhere a box of pieces. EIEIO.
It's a joke. No offense.
Jim
TR3driver
Great Pumpkin - R.I.P
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Makes perfect sense; ODs were much more common in the UK than in the US. Friend of mine said he picked up 6 of them at Stoneleigh for 20 GBP each a few years back. Compared to the hundred of $$ that even a core unit brings here in the US, I'm sure there are people bringing them over.
Still gotta be better than trying to convert a Volvo OD.
Still gotta be better than trying to convert a Volvo OD.
vivdownunder
Jedi Warrior
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It's quite possible tabcon's o/d came from Australia, as many Triumph 2000/2500 type sedans came here with o/d fitted. For a long time now these cars have been purchased cheaply just to rescue the o/d, and the rest crushed for scrap.
I've always wondered why most USA delivered TR's had steel wheels and no overdrive, whereas we with the same long distances to travel, mostly chose the overdrive option and wire wheels. I spent probably two years looking for a TCF series TR3B with overdrive, before having to settle for importing a non o/d car.
However, it wasn't long before the 3B had an o/d fitted. Thereafter it used only 29 litres on a set country run instead of 37 previously.
Once you've had an o/d TR, especially one with 2nd, 3rd and top hooked up, they are such addictive good fun, and so practical in saving engine wear and fuel consumption, that it's hard to accept a car without one.
Viv.
I've always wondered why most USA delivered TR's had steel wheels and no overdrive, whereas we with the same long distances to travel, mostly chose the overdrive option and wire wheels. I spent probably two years looking for a TCF series TR3B with overdrive, before having to settle for importing a non o/d car.
However, it wasn't long before the 3B had an o/d fitted. Thereafter it used only 29 litres on a set country run instead of 37 previously.
Once you've had an o/d TR, especially one with 2nd, 3rd and top hooked up, they are such addictive good fun, and so practical in saving engine wear and fuel consumption, that it's hard to accept a car without one.
Viv.