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Improved TR Rear Main Seal Kit

MGTF1250Dave

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Aloha All,

I just received the new rear main seal kit from TRF. I believe these are fabricated by Alexander Racing Enterprises (ARE). This seal kit does not require any machining of the crank shaft, the original aluminum labyrinth seal pieces are machined to accept a VITON lip seal. The kit includes an alignment tool, the modified two piece aluminum seal ring and the VITON lip seal. There is a core charge for the aluminum seal ring, but the package included an addressed jiffy bag for me to return my original ring for credit. There is an 4 page illustrated installation guide and the job seem pretty straight forward.

I haven't installed it yet, but it seems it should seal better than the original and a better option to machining the crank shaft to install a modern seal. I'll let you know how it works soon I hope.
 

Perrymip

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I also won't be able to report on the installation for some time, but everything about this solution seems to me very attractive, especially no alteration of the crank, which has produced so many horror stories. And the (correct) mandrel for installing the seal is, itself, a major contribution. Joe Alexander is quick to point out that the project was initiated in Germany by "Mad Marx"
 

TR3TR6

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Dave:

Do you have to pull the engine to install the seal or can it be done by removing the transmission, clutch and flywheel?
 

TR4nut

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I installed that seal about a month ago, but have yet to fire up the engine - yes I agree I like the concept, money-wise it wasn't much different that the modern seal alternative since there is no machine shop work to remove the scroll.

People have changed out the old scroll seals without pulling the engine, but with the work on the rear main I think its best to do it with the engine out of the car when rebuilding.
 
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MGTF1250Dave

MGTF1250Dave

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Aloha Terry,

I would agree with Randy that this probably best if installed while rebuilding the engine. If installed with out using the centering tool, which requires the crankshaft to be out of the engine, there is the chance the new seal will not be centered. I believe this would result in excessive wear on tight spots and possible leakage from gaps in loose spots.

I think it might be possible to install this with the fly wheel removed, but I satisfactory results would be a crap shoot. Much like installing a replacement labyrinth seal without using a center tool.
 

TomMull

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Although MadMarx does suggest that it may be possible to put in this seal with the crankshaft in place, the instructions clearly specify the crank out. You have to pull the crank for a couple of reasons: 1. The seal requires compression from tightening the bearing cap (as does the original aluminum seal) which is why you get the mandrel, and 2. The seal seats on a tiny bit of the crank just forward of the flywheel flange, which will probably require a slight polish.
There is a lot to like about this seal, no crank grinding and it supplements the original seal,rather than replacing it, but I've decided not to use it even though I'm in the midst of a rebuild. I'll use the original Triumph aluminum "seal" which has never leaked significantly in the past. If, however, I ever have a rear seal leaking problem, I would certainly try this first.
Tom
 
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MGTF1250Dave

MGTF1250Dave

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Aloha Dan,

I have the engine with the new rear main seal installed in the car. I have driven about 70 miles in addition to an initial run of about 20 minutes at first start up. I have not noticed any oil drips from the rear of the engine or bell housing area, but perhaps it is to early to be sure.

I think the sucess of this new improvement is that you keep the original scroll seal and are adding a back up with the modern seal behind it. The kit I bought from TRF included everything needed to install it. The machined aluminum centering tool is dimensionally correct and yours forever. Although this kit costs a little more than the alternate modern replacement seal, there is no machining of the crank shaft required. So that additional cost needs to be considered when comparing prices.

I think after about 500 miles I should know for sure if my install was a success.
 

TR4nut

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I've started my engine up only. Still have the very minor drip, but I can't say it is the seal, I had a bad valve cover gasket which contributed, and I still worry about the felt around the rear main. But overall, I am sold on the seal.
 

PatGalvin

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Hey Guys

Question for the brain trust - Is anyone using the Moss seal retrofit (Land Rover rear seal, I think - the one that requires you to machine off the crank scroll) with good success? My rear seal retrofit from BPN leaked badly when I started my engine (last summer, sheesh that was a long time ago) and I'm hoping and wishing that I perhaps installed it incorrectly. After I finish body work and paint, I'm going to pull the engine and take another crack at it. Looking for anyone that has this modern rear seal and has had good (low or no leak) success. Moss and BPN claim they've sold thousands. Do they all leak?

Thanks. Hope you don't consider this a hijack of the thread. Seemed on subject to me.

Pat
59' TR3A
 

TR3driver

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I am not, but many people have had trouble with them leaking even worse than the original seals. One of the big problems has been that many of the instructions sheets give the wrong dimension for machining the crank.

There are some good tips here https://www.tonydrews.com/uncle_jacks_engine_building_tips.htm
and here
https://personal.linkline.com/koblinger/trsc/tech%20articles/mainseal.htm
on ways to get the conversion seal to seal.

But for anyone who has not already had the crank machined, I strongly recommend the more recent conversion that uses a Viton seal and does not require alteration of the crank (except perhaps some polishing in the new seal area). This conversion was invented by a Triumph racer in Germany, because he could not get the old conversion to work for him, and I've only heard good things about it. (Mine is still in the box, waiting for one of those round tuits to appear.) (This is the conversion that Dave started this thread about.)
 

PatGalvin

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Hi Randall
If I were to do it over, I'd certainly use the new style seal and keep the crank scroll. Mine leaked pretty badly - surely much worse than the stock scroll seal.

But I've already had my new engine balanced, so I really want to try and make the Moss/BPN rear crank seal work, if possible. My crank is machined EXACTLY at 2.5", per the instructions (within 0.0001"). Uncle Jack recommends 2.525". Really hate to lose all my good machining work and punt to a new crank.

So, has anyone had good experience with the Moss/BPN crank seal? (searching for some encouragement).
 

TR3driver

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David_Reaka said:
Hi Randall, Would u please give details about the rear seal u are referring to. Regards, David
Basically, it does two things :

1) Improve the original scroll seal (by correcting what many believe to be an error in the original factory manual). A new seal setting tool is part of the kit (HP600 @ TRF).

2) Add a Viton lip-type seal to stop any oil that makes it past the scroll seal.

And best of all, it doesn't require modifying the crank. If you are unhappy with it, just install a new original seal and you're back to the stock configuration. There have been more than a few people burned by the other conversion, as it's somewhat difficult to grind the crank larger (although it can theoretically be welded up and ground down).

Here's a link to the developer's instructions (note that the TRF kit includes a scroll seal that has already been machined): https://www.tr4-racing.de/download/splitseal.pdf
And a TRF catalog page showing the kit https://trf.zeni.net/TR2-TR3Handbook/7.php

Let me know if you have any other questions.
 

TRMark

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VTR's publication, The Vintage Triumph had a great article several months ago titled "Sealing the Wetliner". That was the first I heard of Mad Marx's new seal. I machined off the scroll on my TR crankshaft years ago and used one of he Rover seal conversions. Didn't leak a drop till I put oil in it. Not much of an improvement.
 

Jersey_Royal

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I have a Mad Marx Seal on order with TRF for my Tr3, unfortunately they are out of stock. They are having problems sourcing the machined aluminium section.

Thought i would let you peeps know.

Cheers

Guy
 

TR3driver

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MGTF1250Dave

MGTF1250Dave

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Randall is correct. Joe Alexander fabricates the seals for TRF along with several other "improved" parts for TR's. He makes them in the US for Christan Marx, known on this forum as "Mad Marx". Here is a link to his website:

https://www.tr4-racing.de/eng/madmarx-racing.html

and it includes a link to a down loadable installation manual. The stock aluminum seal halves are machined to accept the viton seal, so a stock of these items is essential to making the kits.

I agree with Randall that you may be able to get one by contacting The Vintage Racer and offering to provide the stock aluminum seals up front. I believe you also need to order the centering tool seperately from them since it does look like it is part of the kit.
 

TR3driver

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MGTF1250Dave said:
I agree with Randall that you may be able to get one by contacting The Vintage Racer and offering to provide the stock aluminum seals up front. I believe you also need to order the centering tool seperately from them since it does look like it is part of the kit.
That's right, forgot to mention that. And I know Joe (ARE) supplies them, as that is where I got mine. He just gets busy with other things (like racing Triumphs) from time to time, and may not be any faster than (or even as fast as) ordering from TRF and waiting for the parts to come in.
 
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