TR4/4A Back to the Overdrive-TR4A

[KVH]

I just took my interior out again, along with the center saddle and radio.

I'm determined to get that pinch bolt on the OD operating shaft to quit slipping. I've machined the clamp just a bit to allow more room for the crimping to work, but I do have a question.

What's causing it to slip in the first place? There appears to have been just shy of 1/16th of an inch to crimp before this exercise, and the OD was working for about 3 weeks. Is a lock washer needed? Is vibration causing the loosening?

I must say, after it slips I don't detect the bolt being loose at all, so it's a bit of a mystery.

Also, I see a slight leak at the operating valve plug on top of the OD. Can I ignore that or do I need to chase that down next? A new plug won't be cheap.

thx

 

[JerryVV]

I think that valve cap has a copper washer. You might try to tighten and loosen a few times to burnish it into sealing

 

[KVH]

Yes, thanks, I'll try that with the copper washer.

It seems as if I only learn from experience--and from this board. Not too much is self-taught.

I just emptied my transmission and overdrive, and I'm not all that happy. I'd rebuilt the OD just a short time ago, and was expecting to see clean and clear GL4 fluid. Instead, my magnetic drain plug had a little clump of dirt around it, and some fine steel, silver colored "bits" in it.

I don't imagine that's normal, and I hope it's nothing from the OD. I really tried hard to rebuild that right--new thrust washer, tested claerances, new bearings front and rear, and about 100 posts learning from everyone (Randall is a genious of course).

Maybe it's all coming from the gearbox. It's not "terrible" looking, but I do see some little tiny specs or shavings, silver in color.

Time will only tell, and the worst that can happen is that I'll have an excuse to learn all about the rebuilding of a gearbox, and more about the OD again.

 

[TR3driver]

Oops, sorry, just saw this thread.

My opinion, the clamp isn't coming loose at all; rather it moves a tiny bit every time the solenoid slams the lever up (or maybe even just when actuating against full pressure). Since there is a bit of extra movement at the normal adjustment, the OD continues to work for some time. At any rate, I had exactly the same experience, several times, hence my determination to be able to more easily readjust and tighten without disassembling the car. Last time around, I torqued that SHCS until I thought the wrench would snap, and it has held for over a year now.

I know you don't want to hear this, but I wouldn't keep driving with it making shavings. It's amazing how fast the cost to rebuild goes up when you have to start replacing hard parts, like the annulus and planetary gears.

 

[KVH]

. . . At any rate, I had exactly the same experience, several times, hence my determination to be able to more easily readjust and tighten without disassembling the car.

OKAY, but even if I have as good a setup as you created, I have to be able to access the adjustment lever to insert a 3/16 pin. That's impossible due to lack of clearance with the transmission tunnel. I made a little bent rod that "sort of" fits but I still have to set it by guess and feel. Is that what you to, or did you cut an access hole in the other side of the tunnel?

I know you don't want to hear this, but I wouldn't keep driving with it making shavings. It's amazing how fast the cost to rebuild goes up when you have to start replacing hard parts, like the annulus and planetary gears.

Is the thick black "goo" a sign of bad things as well. I can't imagine that's some stewed up metal brew, but maybe so. Also, there wasn't much to the OD, so unless that sun gear is deteriorating I'm wondering if the issue is something in the gearbox. And what would that be.

I know it's no consolation, but it runs and shifts great, and the OD is very quiet and smooth. So where's that muck coming from? Maybe I'm deluding myself, but let me try this on you:

I never had a magnetic plug before, and I didn't clean out the gearbox because I left all the gears in and didn't tackle rebuilding it along with the OD--and didn't want to "rinse" it with solvent or anything like that. Perhaps the plug just gathered up all the old muck? Am I just searching for the sunny side of life?

 

[TR3driver]

OKAY, but even if I have as good a setup as you created, I have to be able to access the adjustment lever to insert a 3/16 pin. That's impossible due to lack of clearance with the transmission tunnel.

Well, maybe a TR3 has more room at that point than a 4A. I cut a length of pin that would just fit into the space between the arm & cover; then used needle nose pliers to put it into place. Had to be careful not to slide it in too far, or there wouldn't be enough still sticking out to remove it.

Cutting an access hole would probably have been easier, but I am somewhat loathe to cut up the original sheet metal if I can avoid it.
<div class="ubbcode-block"><div class="ubbcode-header">Quote:]Is the thick black "goo" a sign of bad things as well. I can't imagine that's some stewed up metal brew, but maybe so. [/QUOTE]
I could be wrong, but that it is what I think it is. Very tiny metal particles, mixed with gear oil.
<div class="ubbcode-block"><div class="ubbcode-header">Quote:]
Also, there wasn't much to the OD, so unless that sun gear is deteriorating I'm wondering if the issue is something in the gearbox. And what would that be.[/QUOTE]
From the gearbox, I'd guess you're looking at particles from the surface of the countershaft or its bearings.

From the OD, one possibility is that the planetary gears are rubbing against the face of the annulus. Somewhere around here, I've got an annulus that was ruined by a bad bearing in one of the planetary gears. The OD it came out of wasn't making any bad noises, was just slow to engage sometimes (low oil pressure) and always had some "fuzz" on the magnets at every oil change.

<div class="ubbcode-block"><div class="ubbcode-header">Quote:] Perhaps the plug just gathered up all the old muck? [/QUOTE]
Well, could be. Worth a try, I guess.

Side story: When I got my first Stag home, one of the first things I did was to change the oil and install a magnetic drain plug. Next oil change, I found part of a timing chain roller stuck to the plug! Now timing chains are a famous weak spot of the Stag motor and since the pistons hit the valves, the damage from a broken chain can be severe. So I kind of panicked and immediately pulled the timing cover off, only to find that the timing chains were in great shape! The chunk of roller must have been from some previous chain and somehow had been roaming around the oil pan.

 

[MichaelG]

"OKAY, but even if I have as good a setup as you created, I have to be able to access the adjustment lever to insert a 3/16 pin."

The factory equipped O/D cars had a cutout in the gearbox cover to access the solenoid and adjust. A picture is on page 2-304 of the factory workshop manual, or page 56 figure 6:3 of the Autopress: Ken Ball manual

I made this simple modification to my cover when installing the O/D.

You are on the right track....Take more material off the clamp, score the inner surface of clamp with a round file, use some blue loctite and tighten as much as you dare.

 

[KVH]

Seems I can't do anything without affirmation from this Forum!

OKAY, first question is a follow up to the discussion above. Since the transmission and OD share the oil, I guess I have to concede that the metallic sludge on my magnetic drain plug may be from the OD and not from the gearbox. I just rebuilt the OD, so I'm not glad to concede that possibility. However, since I clearly drained the transmission before rebuilding the OD, I have to think that sludge would have drained out if it had been there all along and associated with the gearbox. Correct assumption?

Second, assuming that sludge came from the OD, that would be disconcerting given that I've only put 190 miles on the OD since rebuilding. Also, because I replaced the head and tail bearings, as well as the brass thrust washers, and checked the clearances as best I could with a dial gauge, steel shavings and sludge from the OD would cause me to wonder what I could possibly have done differently. I thought I "had it right." So, if I did things "generally" right on the rebuild, which part is likely the culprit here? The sun gear? Planets?

They looked terrific before my handi-work!

Finally, I'm re-installing the spring loaded side mounted solenoid bracket on the OD unit tomorrow. Mine was leaking despite careful application of Hylomar. I'm concerned that my new gasket is awfully thin. Should I be? It came in the gearbox/OD gasket rebuilding kit. It looks like paper. The one I had (and which leaks) was quite a bit thicker. I can make my own, which I'm inclined to do, but what advice is out there for that gasket?

 

[TRTEL]

Dear KV,
I really think if it all went back together smoothly and all that was changed were a thrust washer and a bushing or two, there is no problem. I worked on these things constantly for about four years (40 yrs ago). They all develop 'sludge'. Most of it gets 'shaved' off the brake ring and probably a bit off the annulus. Race car boxes (for good reason)would accumulate the most.
Though I was thinking that lubricants are so much more superior now that they would cut down on the material you're seeing. Just the design I suppose. And if it were the sun/planetary gears its probably too late, as they do need a close fit. They will make themselves known soon. I would vote in any case to 'drive it till it breaks' (in the words of my old mentor).

tl