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TR4/4A Will a TR3A trans cover fit a 4A?...close?
- Thread starter karls59tr
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vivdownunder
Jedi Warrior
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Doubt the trans cover could be used as the floor cutout is a different shape on the 4A.
The front fixing is different too with vertical bolts on the 4A cover - horizontal on the 3A.
4A floor panels are completely different to the 3A at the outer sill, so that's probably a lost cause as well.
Viv.
The front fixing is different too with vertical bolts on the 4A cover - horizontal on the 3A.
4A floor panels are completely different to the 3A at the outer sill, so that's probably a lost cause as well.
Viv.
Geo Hahn
Yoda
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Too bad -- I had thought about the steel tunnel too.
A friend's TR3A had the gearbox grenade at highway speed in Oklahoma. Damage was so extensive they never found the propshaft. Lots of dents in the steel tunnel from needle bearings and other parts.
Got me thinking about how that lovely fibreboard tunnel on my TR4 would protect me should this happen. A Kevlar alternative would be nice.
A friend's TR3A had the gearbox grenade at highway speed in Oklahoma. Damage was so extensive they never found the propshaft. Lots of dents in the steel tunnel from needle bearings and other parts.
Got me thinking about how that lovely fibreboard tunnel on my TR4 would protect me should this happen. A Kevlar alternative would be nice.
HerronScott
Darth Vader
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Geo,
Wow, what was the failure on that TR3A transmission that caused that kind of damage? I could see the front driveshaft U-joint perhaps but didn't think the transmission in a TR could fail that drastically.
Scott
Wow, what was the failure on that TR3A transmission that caused that kind of damage? I could see the front driveshaft U-joint perhaps but didn't think the transmission in a TR could fail that drastically.
Scott
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I was wondering the same thing? Perhaps it was something like what happened to 'uncle jack' as it was about to debut for the Transamerica run?HerronScott said:
Geo Hahn
Yoda
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It did remind me of the Stag's misadventure though in this case the gearbox remained with the car, though completely severed from the bell housing.
At first he thought he would fix it and continue on to Chicago, then he got the tunnel off and realized the trip plan would change. He found a super nice bunch of people at a garage in Keyes Oklahoma who helped him out for several days. In the end a friend brought a trailer, they took it back to Tucson, put in another gearbox and took off once more for Chicago but this time with the TR3A on the trailer. Arrived in time for the big show they were attending with quite a tale to tell.
The cause of the TR3A failure has not been exactly determined but might be a tooth that had broken off a gear (2nd I think he said) and laid around in the bottom of the gearbox until one day at speed it go swept up to where it could do some real harm. I believe he arrived at this theory by examining the broken gears as one can often tell an old break from a recent break. Yes, he uses a magnetic drain plug.
At first he thought he would fix it and continue on to Chicago, then he got the tunnel off and realized the trip plan would change. He found a super nice bunch of people at a garage in Keyes Oklahoma who helped him out for several days. In the end a friend brought a trailer, they took it back to Tucson, put in another gearbox and took off once more for Chicago but this time with the TR3A on the trailer. Arrived in time for the big show they were attending with quite a tale to tell.
The cause of the TR3A failure has not been exactly determined but might be a tooth that had broken off a gear (2nd I think he said) and laid around in the bottom of the gearbox until one day at speed it go swept up to where it could do some real harm. I believe he arrived at this theory by examining the broken gears as one can often tell an old break from a recent break. Yes, he uses a magnetic drain plug.
TR3driver
Great Pumpkin - R.I.P
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Thanks for posting the link to "uncle jack's" mishap, Andy. I thought of that myself, but couldn't find a suitable photo.
Looking at that photo (and others), it seems clear to me that the countershaft in the bottom of the gearbox (which rides in the uppermost hole in the photo above) was forced down through the bottom of the case. This could happen if, for example, some sizeable chunk of metal got caught in the gear teeth and was forced between the gears by the inertia of the car, acting as a wedge between the two shafts.
Could have been a broken gear tooth as Geo's friend thinks, but I was wondering if perhaps it was a shift fork taper pin that backed out. Early gearboxes had safety wire for those pins, but later ones only had a nylon button that should probably be replaced every time ... only problem is that no one AFAIK makes replacement pins. I meant to ask Tim at TRfest if the shift fork pins were still in place, but didn't get a chance.
Looking at that photo (and others), it seems clear to me that the countershaft in the bottom of the gearbox (which rides in the uppermost hole in the photo above) was forced down through the bottom of the case. This could happen if, for example, some sizeable chunk of metal got caught in the gear teeth and was forced between the gears by the inertia of the car, acting as a wedge between the two shafts.
Could have been a broken gear tooth as Geo's friend thinks, but I was wondering if perhaps it was a shift fork taper pin that backed out. Early gearboxes had safety wire for those pins, but later ones only had a nylon button that should probably be replaced every time ... only problem is that no one AFAIK makes replacement pins. I meant to ask Tim at TRfest if the shift fork pins were still in place, but didn't get a chance.
HerronScott
Darth Vader
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Amazing picture and something I definitely never want to see in person!
Scott
Scott
TR4nut
Yoda
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Regarding the Uncle Jack transmission, I don't know where I read it, but I believe they diagnosed the likely culprit to the countershaft thrust bearing, which on a stag is a needle bearing as opposed to the TR non-needle variety. Evidently one or more needles became loose and then all heck broke loose.