TR4/4A my bad- need tr4 shifter photo

[twigworker]

I took a shot of the underside of the shift tower on this TR4 gearbox before I disassembled it, but screwed the picture up and lost it.

Now I need to see exactly where the distance tubes that fit on each shift rail go.

There are one each on the three main rails and another one on the reverse idler shaft.

If you don't have a photo, a description would work...Example:

On the 1/2 rail the tube goes in front (toward the front of the car)of the fork.

Why did I remove the rails? Because they were jambed up with their detente balls and hard goo from shear age. Was it a chore? Yes. Is it going to be a chore to reinstall the rails and detents? I was until I figured out a "country cure". :wink:

Thanks, Jack

 

[TR3driver]

Will this do?

While it's apart, don't forget to change the shaft seals.

 

[twigworker]

Total BINGO Randal. <span style="text-decoration: underline">Thanks lots.</span>

Shaft seals? I didn't find any when things were coming apart. I am not very familiar with TR g-boxes and wondered about how just the close tolerance of the shaft/bore toward the rear would contain the lube.

Pretty diabolical of the engineers to trap the detente balls and plunger under non removable plugs, but I beat them at their own game.

Doing a complete ground up nut and bolt for this guy so "I'll be back".

Jack

 

[TR3driver]

You should read the gearbox articles at https://www.buckeyetriumphs.org/technical/technical.htm
(which is where the above photo came from).
Although written for a TR250/TR6, the TR4 gearbox is basically identical to the TR250/TR6 box. There are also some very good articles at https://www.vtr.org/maintain-index.shtml (the "Greasy Hands Garage Guides").

I was under the impression they didn't start using those blind plugs until later; but perhaps I've just misremembered. In any case, they're easy to get out. Find a tap that will just bite into the inside of the cup (ISTR I used a 5/16 bottoming tap but maybe it was 1/4"). Drop a spacer over it big enough to pull the plug into, then turn a nut down the back of the tap. Pulls them right out. Mine could have been reused, but I tapped the holes for the earlier threaded plugs anyway.

Where the 3 shafts enter the housing, underneath the extension, there should be a small plate held by 2 bolts. Under that plate are the shaft seals.

Frequently the replacement seals don't fit right, so instead I bought some "double seal" O-rings plus some teflon "backing rings" from MMC

Installing the detents is easy (especially if you tap for the threaded plugs). The fun part is installing the shift interlock and getting it right. It's like one of those puzzles where you have to steer the ball around the holes, except you can't see the ball and the hole at the same time!

 

[twigworker]

Preview
I thought about using some short stubby easy-outs to pull the plugs but instead opted for drilling 1/8" holes in the top of the casting directly above the bores for the detentes, and driving a slightly smaller drift down through them to drive the plugs out. The drift went through the center of the springs for the forward speed rods and pushed onto the plunger for reverse. When I am done I will fill the drilling's with liquid metal and all will be well again.

Thanks for the tip Randal on the seals. They don't seem to show up anywhere in the catalogs, but I will use your knowledge to "make things right". At the moment I am stalling on the rebuild until I can figure out a way to dislodge the clutch release fork from the cross shaft. Heating to red several times hasn't helped it to budge.

Also, no one likes a whiner, but the aluminum material casting for the bell housing on this thing leaves a lot to be desired, very grainy and porous. I have found at least four fractures that will have to be welded up.

Jack

 

[TR3driver]

You really shouldn't rely on vendor catalogs, as they frequently don't tell the whole story. TRF (my personal favorite) doesn't even attempt to publish a full catalog for the TR4.

Instead, get a copy of the factory parts catalog (the seals are item 44) :

 

[TR3driver]

On the clutch fork, are you sure there isn't a broken taper pin inside, or some DPM (dumb previous mechanic) has welded the fork to the shaft?

Most likely the shaft needs replaced anyway (they wear at the bearings), and the fork should move easily once the pin is out. So if it's that badly stuck, my suggestion would be to just cut the shaft and be done with it. One of those cheap angle grinders from Harbor Freight plus an abrasive cutoff wheel will make short work of it.

Yeah, the castings aren't very good. You have to keep in mind, these were cheap sports cars; their low price was a large part of their attraction.

 

[twigworker]

That's the conclusion that I came to on the shaft this afternoon. The two parts aren't welded but it looks like just a little stub of the set pin is still there. I just didn't want to destroy a part that I wasn't sure that I could replace.

I have the parts catalog on order.

I suspect that it isn't "according to the rules" on the forum, but do you know of more Triumph parts vendors, other than TRF and Moss? I don't care to do business with VB. I hate to bash any vendor as there are precious few who are out there to support out hobby in the first place, but I find that I have to do business with TRF sometimes even though it is like pulling teeth to work up an order. Their catalog/numbering system is something out of a Stephen King novel.

Please PM me if you are uncomfortable about publishing the information here.

 

[TR3driver]

The broken pin can usually be removed the same way you got the plugs out. Just drill about 3/32" down through the fork, on the axis of the hole, then use a pin punch to knock the pin out. The fork is plenty beefy, the hole won't matter.

There are lots of other, smaller vendors (some of whom advertise on this forum). But Moss & TRF are by far the largest (and most of the smaller ones actually get most of their parts from Moss).

It took me awhile to get used to it, but now I actually prefer the TRF system, where I can put in a factory part number and get that part. Comes in particularly handy when I'm trying to find parts for my Stag; as many of them are the same part used on TR2-8. In fact, just this morning, I looked up a stoplight switch in the Stag parts catalog, and ordered two of them from TRF. Took me about 15 minutes to place the order (I also ordered an OD switch for the TR3); then only about 2 hours until I had confirmation from UPS that the order was picked up. I didn't want to pay extra for overnight shipping, so the parts should be here next Thursday.

Of course, it doesn't hurt that the owner of TRF is a genuine Triumph enthusiast and owns several of them. Few years back, he even drove his TR3A across country, some 3000 miles, to VTR/Triumphest here in CA.

Oh, and you might find this interesting or even helpful:
https://docs.google.com/open?id=0B2H2NJt34OffYjZmY2ZlYzctYzg5OC00OTc4LWE3MmEtMmRiODI3OTliY2Y4
I'd suggest downloading it to your hard drive if you do.

Pretty much all the common replacement items are usually readily available for TRs. In fact, I'd have to say that parts availability is MUCH better now than it was when Triumph was still in business! (I do wish the same were true for Stags, though.) Although I haven't bought one recently, I'm sure you'll have no trouble finding a clutch shaft.

BTW, the early brass bushings (36998) will fit the later gearboxes, and IMO are a better setup as long as you keep them greased. It's easy enough to drill & tap the shaft for grease zerks, or what I did was to drill & tap the gearbox:

 

[TR4nut]

I suspect that it isn't "according to the rules" on the forum, but do you know of more Triumph parts vendors, other than TRF and Moss? I don't care to do business with VB. I hate to bash any vendor as there are precious few who are out there to support out hobby in the first place, but I find that I have to do business with TRF sometimes even though it is like pulling teeth to work up an order. Their catalog/numbering system is something out of a Stephen King novel.

I find it useful to go to the UK vendors once in a while -

Moss Europe
Revington TR
Rimmer Bros

Even if you don't order from them their websites can be useful for looking up parts. And if you find a part from them, you can try TRF again since the UK vendors still use Standard Triumph numbers.

And if you aren't aware of BP Northwest, I like using them too - much more limited selection but good quality in my opinion and very price competitive.
BP Northwest

 

[JerryVV]

I like dealing with Scott Harper in Warren, Ohio (Team Triumph) 330-392-7176)
His hours are limited, usually 11:00AM to 5:00PM. Mostly used items but can also supply new parts. I'd bet he has those parts in a used bin somewhere

 

[twigworker]

Thank you Randal for the link to the parts book. I will still order a hard copy, but this is great.

Is there also one for the TR3?

Jack

 

[TR3driver]

Is there also one for the TR3?

https://docs.google.com/open?id=0B2H2NJt34OffYWZiN2VlZGMtNTkxMi00NGUzLWE4NzMtMGRkODRkYzU3MDU1

Or you can peruse the entire collection at
https://docs.google.com/open?id=0B2H2NJt34OffMDVmOTZlZWItYTcyMy00ZDhkLTliOWEtOWU1OWRhNDZhYmRl

Lots of them are less than perfect (most of the scans are not mine), and I do try to improve them from time to time. So if you find a particular problem, feel free to let me know. And you can check back from time to time.