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TR2/3/3A TR6 overdrive filter /magnet placement??

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GTP1960

GTP1960

Jedi Knight
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my question is:
what goes in first? Magnet ring or filter?

mine had the magnet sitting on the lip of the filter.
(Magnet ring is concaved, bowl shaped, slightly distorted, but not bad)

but the image in the moss catalog appears to have the filter sitting on the mag. ring & mag. Ring resting inside the cup of the plug?(#9 & 10)


Thanks.

Guy.
image.jpgimage.jpg
 
The order should be as the Moss illustration.
1) filter
2) magnet stack
3) Drain plug with sealing washer


There should be a stack of three magnet rings

M.
 
Thanks for clarifying that M.
i would not have picked up on the stack of three magnet rings.

another delay, while waiting on Moss order! Oh well, at least they are quick shippers.

Though the transmission has performed well,
I have not been happy with the workmanship of this rebuilt transmission.
but it's always buyer beware if you can't do it yourself.
 
CJD recently suggested adding an O ring on the drain plug in addition to the washer which I'm going to try.
 
sail said:
CJD recently suggested adding an O ring on the drain plug in addition to the washer which I'm going to try.
Click to expand...

I plan on trying the O ring also.
my housing is pretty scratched up.
i found that a standard 2 3/16" ring is a good fit.
question is; thick ring or thin ring?
Install with lube or dry?
image.jpg
 
Randall mentioned making a overdrive plug wrench from a large socket.
that would be ideal, if you have the know how & skill.
but this wrench from Moss saved me a lot of trouble, and potential damage to the plug .

(though it is pricey at approx. $60.00 bucks)

image.jpg
 
GTP1960 said:
I plan on trying the O ring also.
my housing is pretty scratched up.
i found that a standard 2 3/16" ring is a good fit.
question is; thick ring or thin ring?
Install with lube or dry?
View attachment 43184
Click to expand...

Hey Guy...I just responded to your PM that the o-ring I used was on the thicker side, but looking at your picture, I think mine was about mid-way between the 2 in your pic. Of the 2 you have, I would lean towards the thinner one. Try it and make sure you feel the plug hit softly on the o-ring before you feel the solid contact of the plug against the case. If there is little or no compression feeling as you install the plug, then go with the larger size. Just lightly lubricate the ring with oil, and there is no need to install the plug overly tight.
 
I received the mag. Stack from Moss today.....
only thing that worries me is the filter sits proud on the stack, not "in the stack".
the filter diameter is to wide to fit inside the stack.
therefore the base of the filter does not slide on to the post in the cup of the plug.

i really want to get this overdrive right the first time, since it's "right or refill " the gearbox oil.

your thoughts appreciated.
 
I'm glad you posted this. I missed that there is supposed to be a magnet at the filter when I rebuilt mine. I'll have to order one too. Watching to see how you fit it in!
 
Well if I don't hear otherwise, I think I'll leave the original concave mag. Ring on the lip of the filter (as I found it ) & reduce the base to two rings in the stack instead of three. Hopefully, The filter should be able to connect with the post on the plug & secure it..
otherwise the compression would distort & stress the filter ( if the filter were resting on a 3 ring stack).

Fwiw: there was a definite "silver sheen" on the original concave magnet ring.
no big partials, but it was there, like a shiny paste.
So I think the magnet rings are important.
 
Thanks, Guy. The oil in mine had turned to tar, so I think the magnets got tossed out with the tar...


 
Manohman.....how did you ever clear that goo?

that reminds me: I've got the original non- synchro gearbox sitting over in a corner:
need to drain it & flush it.

any suggestions on flushing it?
 
Last edited:
Here is how mine came to me with 3 magnets in the bottom then filter which does rest on the peg. It's later production A type unit.
IMG_2028_zpsabaz5dm1.jpg
 
CJD said:
I'm glad you posted this. I missed that there is supposed to be a magnet at the filter when I rebuilt mine. I'll have to order one too. Watching to see how you fit it in!
Click to expand...
The magnets were only used on later ODs, with the notches in the drain plug and no center post in the screen. Earlier units with the smaller hex flats on the plug, and a bolt through the center of the screen did not use them originally.
However, I found that the earlier setup could take one magnet ring (not all 3).

I also like to run a magnetic drain plug in the main gearbox. Moss & TRF sell the Triumph style optional plug, which has a big hex head on it and sticks out by 3/4" or so. However, I prefer the hex socket magnetic plugs available from McMaster Carr, which install flush to the surface.
https://www.mcmaster.com/#magnetic-pipe-fitting-plugs/=12tjzjo
 
Sorry to diverge from the original thread, but I am wondering which is considered the better overdrive drain plug, the one with the notches or the one with the big hex head. Also, are they interchangeable if the center bolt is used with the hex head one, but not with the notched one? Thanks!
Regards, Bob
 
sail said:
Here is how mine came to me with 3 magnets in the bottom then filter which does rest on the peg. It's later production A type unit.
View attachment 43271
Click to expand...

that's an unusual filter. ( I haven't seen one with a inner circular ridge like that).
my filter has a less flexible inner basket weave that would not re-form well.

i did as Randall suggested and used one mag. ring at the base of the OD plug and a magnetic plug in the gearbox.
however next year ( or next time I drain) I'm switching to the mag. Hex socket type.
That big post sticking straight down is just asking to be knocked off.

I went with John's suggestion of an O-ring for the OD plug. (Used the narrower ring, pictured above & only snug tight , like a spin on oil filter.)
just took it out for a test drive & see no leaks yet.

any opinion about Teflon tape on the drain plug threads?

Thanks and best regards
 
TR3driver said:
The magnets were only used on later ODs, with the notches in the drain plug and no center post in the screen. Earlier units with the smaller hex flats on the plug, and a bolt through the center of the screen did not use them originally.
However, I found that the earlier setup could take one magnet ring (not all 3).

I also like to run a magnetic drain plug in the main gearbox. Moss & TRF sell the Triumph style optional plug, which has a big hex head on it and sticks out by 3/4" or so. However, I prefer the hex socket magnetic plugs available from McMaster Carr, which install flush to the surface.
https://www.mcmaster.com/#magnetic-pipe-fitting-plugs/=12tjzjo
Click to expand...

Thanks Randall...it was bothering me when I thought I had lost a part!

I can say that after seeing what happens to gear oil when it sits for decades, I've been spinning the shafts on all my tranny's and diffs I have stored...to keep the oil "mixed"!
 
TuffTR250 said:
Sorry to diverge from the original thread, but I am wondering which is considered the better overdrive drain plug, the one with the notches or the one with the big hex head. Also, are they interchangeable if the center bolt is used with the hex head one, but not with the notched one? Thanks!
Regards, Bob
Click to expand...
I kind of prefer the later design; but I wouldn't bother converting just because of that.

In both cases (IMO) you need a socket that fits the plug. Too many mechanics tackle the later plug with a BFH and drift, which can easily distort the soft brass. I don't recall the size offhand, but ISTR I wound up with a metric socket that had the lip ground down to fit the early plug. I may have remembered wrong, though, that was a long time ago and I don't have it handy to check.

The plugs interchange, but you have to use the screen that matches the plug. To use the early screen, you also need the center bolt, washer and spacer that hold it in place. Also, many (most?) later units lack the threaded hole where the center bolt screws in for the early screen (although it wouldn't be too hard to add).
 
I have the older type on the overdrive on my TR250, which I got from John Esposito. I like the older type and I have found that a 31mm 6 point socket fits it very good. By using a socket it is easier for me to tighten and loosen than the notched type. I currently have the notched type on the overdrive I rebuilt for my TR3, but I'm going to convert it to the older type so I can use my 31mm socket on it. I have tried fitting the old style plug with the screen that was in my TR3 overdrive and it seemed to fit ok ( not sure if I have old style screen or newer style screen), but it appears I will be able to use only one magnet under the screen. I have not finalized my conversion to the older style plug yet, so I'll know later if I can use more than one magnet with it.
Regards, Bob
 
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