Restoration of 2358R

[Certified Lotus]

Thanks Tom, but I still have a long way to go. All my rebuilds have every part cleaned, repaired, painted or rebuilt/replaced. When I am done they are “new” old cars. Usually as good or better than when they came from the factory (With a few enhancements).

The 352 Transaxle has no “updated solution” for the shifting. Everyone says if you pay attention to the u-joints and bushings and adjustment it’s pretty good. The 365 Transaxle has an updated cable shifter solution that I read works nicely.

At least the shifter will function as designed from Lotus.

[GavinT]

Additionally, all my links have multible holes drilled in them for pins to secure the location of the final adjustment. Some of these holes are very large suggesting bolts were used instead of pins.

My question is, if you had thin lock nuts to secure the u-joints in place, the pins would not be taking the full load each time you shifted and rotated the links. Am I thinking about this correctly?

Pardon my humble opinion because I'm not really familiar with the TC linkage . . just going by what I see in your pics.

The design appears to rely on the pins through the uni-joint shafts.
I expect this is so that when the uni-joints are replaced, the whole linkage is restored to OEM alignment with respect to the relationship between the front and rear sections. Presumably this is due to there being minimal adjustment available elsewhere, correct?

I'd think thin lock nuts might be of marginal benefit because you can't really apply full torque to those.
Looking at your pics, the pins seem to be small.

What is the diameter of the threaded shaft?
It's normally considered safe to use a pin that doesn't exceed one third the diameter of the shaft.
What type of pins are they? - seloc pins?

Have you considered spirol pins?
Spirol pins will accept shock loads better and they're also more forgiving of less than perfect holes.

If none of that works out I'd be sorely tempted to cut off those threaded shafts and weld on a larger diameter threaded portion . . and of course, drill/tap the bungs in the shift tubes to suit.
That way you get the benefit from using a larger pin.
And of course, you'd need to change the rod end on the swivel part to accommodate the larger shaft, but hey . .

That's my 2 cents for what it's worth.

[Roger]

My TC is but 13 numbers away from yours (2345R). It has a 13mm shaft too, but no bush and the link fits with no issue, so  I imagine your theory is correct.

As for the u/j, I didn't like those pins so threw them away and use Loctite and locknuts. No sign of movement yet!

[Roger]

Oh, and by the way....
The 365 box has the same kind of linkage as the 352, just the rear link is a bit longer.
My locknuts aren't thin, if I remember I'll take a photo when I'm  at the car later today.
The tubular bit of the bracket that holds the heim joint had slipped down over the rubber bush on my car too. I glued the bush back in place, and also fitted a washer at the bottom of the tube so it can't slip down. It's therefore not fully rubber-insulated,  but I can't say I've noticed.

[tedtaylor]

Glen, you report: "Installed the "A Pivot Bracket" to the bell housing (Note that you cannot add a lock washer to the bolt as the A-Pivot is too close to the bolt head and a lock washer makes the bolt head too proud interfering with the A-Pivot).  Then I installed the A-Pivot."

Have you considered grinding the hex head down on the bolt?  Certainly grinding down the head the thickness of a lock washer will still give plenty of wrench grip and satisfy locking it down (especially if you add the Loctite)

[Certified Lotus]

Ted, I actually did think of that but when I did the measurements the amount of material that had to be removed to fit the right size lock washer for this bolt was too much. I did research thin head cap screws and washers, but had to buy 25 at a time to get a good price. Lock-tite is a better solution.

[buzzer]

On the lock nut issue, I did manage to try this when I was putting my linkage together. I could not get it to hold well enough. As soon as you put some sideways pressure to engage reverse or 5th it moved. Be good to find another solution that was easily maintainable

[Certified Lotus]

GavinT, Buzzer and Roger,  all interesting comments on the shift linkage. I’m scratching my head on the multiple drill holes on the shift tube (links) threaded areas as it is oblivious that the small pins broke and larger holes where drilled for larger pins. Same on the threaded stock on each side of the u-joint. I’m wondering if these were examples of bad backyard mechanics or shops who dealt with this all the time and knew what to do.

Roger used locktite and locking nuts, without pins. Buzzer couldn’t get locking nuts to hold.

GavinT raises a good question, are the threaded studs on the u-joint pre-drilled from the factory and the pin location is just for placement so the adjustment is to factory spec? I don’t know, I haven’t seen an OEM link u-joint that is new. The threaded stock is 1/2 inch and one of my u-joints has 1/8 inch holes drilled for pins and the other is smaller and larger holes for pins.

Does anyone else have further insights to the 352 Transaxle shift tube assembly?

By the way, the new u-joint assembly that RD sells doesn’t have any holes predrilled and it comes with locking nuts.

[Roger]

Here are my locknuts, gripping tight and I cannot imagine why not.

[GavinT]

G'day, Certified,

If your threaded shafts are 1/2 inch, then you should be able to use a ~ 4 mm pin comfortably.

Not having any prior experience . . but the RD uni-joint assembly in your last pic doesn’t overly excite me.
Those type of assemblies are often used in race cars partly because they’re compact and easy to install - no problem.

I reckon they’d exhibit a less than useful life in a road car mainly because of the number of gear changes. The ‘legs’ of the uni-joint are quite narrow and as far as I can tell, they don’t use needle roller bearings. Is that correct.
This leads me to the worry that we’re all familiar with . . i.e. even a small amount of wear at the uni-joint is magnified greatly at the gear stick.

Having said that, it’s not clear to me that the OEM uni-joints use needle rollers either, but it looks like they might. Is that correct?

Then there’s the issue of originality.
If originality is of less importance than functionality, I’d go for a steering joint of some kind as these are more suited to the intended function IMHO.

If you’re happy to do some fabracobbling and don’t want to deal with splined shafts, then perhaps the common Double D shafts and uni-joints are worth considering.
I reckon one of these would outlast the car!

[seniorchristo]

 "are the threaded studs on the u-joint pre-drilled from the factory"

Glen
Holes for roll pins would not be predrilled on replacement parts.  The parts (collar and shank) must be drilled together as a unit to ensure a tight fit for the roll pin.  I think one solution is to replace the u-joint and drill for a new roll pin while leaving enough room for a locknut.

It looks like the PO even tried to weld the u-joint shank to the collar after all else failed.
Also, Pegasus sells much higher quality (and expensive) Apex universal joints solely designed for shifting.

[seniorchristo]

https://www.pegasusautoracing.com/productselection.asp?Product=1490

[Certified Lotus]

Thanks for all the insights and information.

Roger, good to know that retaining lock nuts work with the use of locktite. I have one original u-joint that seems to be in good condition so I may try that.

GavinT, the joint from RD is manufactured by Lovejoy who has been making Commerical unjointed since the 1940’s. It looks like they had these custom made with the threaded studs. Here is the chart regarding load factor. I think it should hold up fairly well, but might want to add the boot to keep weather off of it.

http://www.lovejoy-inc.com/products/universal-joints.aspx

Chris, I would agree that the pin holes are most likely drilled after install to match the collar and stud holes. It was suggested the ujoint studs came pre-drilled, which is why I asked the question who has installed an OEM complete shift link system. The Pegasus helicopter ujoints look very cool, but they will require welding custom threaded studs to them, which will make them exceptionally expensive. I‘ve made note of this ujoint for future reference. Thanks.

Does anyone else who has done a done a full shift link install for a 352 Transaxle have advice?

[seniorchristo]

Glen
If I remember correctly there was considerable play in the new Lovejoy joint from RD.  I think the Apex joints are a much higher quality item.  If welding is considered impractical, the joint could be bolted to a proper stud using a saddle washer and perhaps Loctite bearing mount(?).  I think this would eliminate all play at this location.  I guess there would still be some flexing in the attachments however.  Just an idea to consider.
https://www.pegasusautoracing.com/productselection.asp?Product=3077-002

[Certified Lotus]

I wouldn’t say “considerable play” in the Lovejoy ujoint, it did have a little play. But more to the point, the whole OEM shifting solution is a bit wonky. I’m not sure enhancing the center u-joint at considerable cost without enhancing the shifter and the rear u-joint that attaches to the transaxle will produce dramatic results. I would think a solution needs to be designed for the entire shifting system.