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TR4/4A Rear main seal

carpecursusII

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I know this has been beaten to death so I'll try and keep it short. Reading through everything here it would seem I want to avoid the revington seal conversion and not machine my crank. I have looked at the ARP replacement kit with the lip seal and it looks pretty good. When I removed my original rear seal it had felt packed in the channel just aft of the scroll seal, the car did not seam to leak much oil, it certainly did not leave any drops on the floor maybe just a light coating on the back of the engine. I know this motor has been rebuilt before so I presume this was added.

My questions are:
1) How good is the ARP seal kit and how easy is it to install, I will be doing the work and don't want to add more headaches.
2) Has anyone else seen felt packed into the aft channel of the seal before and is that a viable solution to the probem. If so, where do I get more felt rope to replace it with?

Thanks
 

tinman58

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I like the lip seal. Easy to install, just shorten your flywheel bolts. I don't quite understand where you are talking about with the felt rope. (pictures)!
 

charleyf

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I have installed one of the ARP ( Alexander Racing products) rear seals and found it to be very straight forward. You do need the centering tool as well as the seal. The felt packing is the traditional way to seal that channel. The felt comes with most lower engine rebuild gasket sets. But the felt is not alone in there. The manual says to cut the felt in short pieces and soak them in Wellseal ( TRF # WS100) and then pack them in as tight as you can. This is still done with the ARP seal. A call to TRF should net you both the felt and Wellseal.
Charley
 

TR3driver

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2) Has anyone else seen felt packed into the aft channel of the seal before and is that a viable solution to the probem. If so, where do I get more felt rope to replace it with?
Interesting concept. Just to be clear, I believe you are talking about adding rope to the oil return groove in the original seal; not the felt that goes between the bearing cap and the block.

'Rope' seals were common "back when"; the much-maligned scroll seal was actually an upgrade as the rope frequently didn't last very long. A quick Google shows that several sources still carry the rope, eg Summit https://www.summitracing.com/parts/fel-bs3165?seid=srese1&gclid=CPv-kb60yr4CFUVqfgodqFcAiw

I will definitely be going with the "Mad Marx" Viton seal, as supplied by Alexander Racing Enterprises (not to be confused with American Racing Products). It was developed by a TR racer in Germany, who tried all the other seals and found them lacking. Apparently you can be banned from some race tracks, for leaving even a single drop of oil on the pavement.

One of our local club members tried the older conversion, where the scroll gets machined away. The results leaked far worse than I've ever seen an original seal leak! We're talking a stream of oil, not just an occasional drop.
 
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carpecursusII

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Randall, you are correct I am talking about the return groove not the felt that seals the bearing cap to the block. I have had club members who have used the revington seal with success when machined to 63.5 mm but I would still lean toward the ARP seal if I upgraded. Do you know if that summit link you posted would be the correct size, I am temped to order it and see how it works.
 

TR3driver

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Do you know if that summit link you posted would be the correct size, I am temped to order it and see how it works.
I don't know, but it looks kind of big in the photo. IIRC the rope for my old "stove bolt" Chevy motor was close to 1/2" in diameter and the groove was about 3/8". I don't recall the groove in the TR seal being nearly that big; but can't say I've ever paid all that much attention to it.

The factory scroll seal can actually work pretty good, if you re-arrange (or lose entirely) the factory "PCV" system, and use the right size mandrel to install the seal. (The factory workshop manual is apparently a misprint.)
 
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carpecursusII

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I am running the factory PCV system and it is operating properly. I suck from the valve cover and into the intake. How would I re-arrange it?
 

TR3driver

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I am running the factory PCV system and it is operating properly. I suck from the valve cover and into the intake. How would I re-arrange it?
One way would be to remove the plug and install the TR2-3 style road draft tube. But if you've got the early setup with just an open tube to the air filters, then just freshening the rings & cylinders would probably be enough.

The problem is that, at full throttle and especially if the rings & cylinder walls are a bit tired, there is quite a bit of exhaust that makes it's way past the rings and out through the crankcase. You want to make sure it can exit the crankcase easily and not build up pressure there. TR4A (and I've been told some TR4) used a valve in the line from the rocker cover that greatly limits the amount of flow; especially at full throttle when there is no vacuum in the intake manifold. The pressure build up in the crankcase tends to blow oil out everywhere, including the rear main seal.
 

DanB

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I have installed one of the ARP ( Alexander Racing products) rear seals and found it to be very straight forward. You do need the centering tool as well as the seal.
Charley

Feedback on Joe's seal from me... I installed it this past spring. Due to some transmission trouble, I pulled the tranny out last night. It looks like the new seal is leaking as bad as it ever did before. There is a good bit of oil inside my bell housing.

Dan B
 

charleyf

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Dan,
I have had no reason to get inside my bell housing to see if there is any leak there. But I have put 8-10,000 miles on this car.
Charley
 

tinman58

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Dan B.
check the lenght of the flywheel bolts. The arp bolts were I little long and wore out the seal. The fix was shorten the bolts on a grinder. After 6000 miles on the new seal, no leak...
 

PatGalvin

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As info, I installed the Revington lip seal, machined my crank to exactly 2.5 inches, and it doesn't leak a drop (after about 500 miles). So, I'm quite happy so far. Make sure your aluminum oil gallery plug on back of engine block is sealed tight, or replace it. Mine leaked and I mistook that leak for a rear seal leak. Was a very expensive and unnecessary repair on my TR3A. Best of luck!

Pat
 

sp53

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I have not started my engine yet after installing the Mad Max seal, but it looks like it should work fine, and it was not too difficult to install. Read up on it and get both sets of instructions. One suggestion I would make is to make one of those stock rear main cap pullers that pulls the rear cap straight up. I suggest this because there is a sequence of dry fits as you go through the installation process and the rear cap is a very snug fit. Half of the new seal stays in place when you mate the two together and then take the crank back out to put on the seal, so you cannot wiggle the unit back and forth too much. You want a starlight pull up. Chris maintains with his instructions to also follow the shop manual, and I believe the manual shows how to make that simple lifting puller dealie with a couple of screws, at least the Haynes does.
 

TR3driver

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Feedback on Joe's seal from me... I installed it this past spring. Due to some transmission trouble, I pulled the tranny out last night. It looks like the new seal is leaking as bad as it ever did before. There is a good bit of oil inside my bell housing.

Dan B
Are you sure it's the crank seal leaking? There are several other places that can leak, including a couple of plugs and the seams between the rear main cap and the block.
 

TR3driver

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I have not started my engine yet after installing the Mad Max seal, but it looks like it should work fine, and it was not too difficult to install. Read up on it and get both sets of instructions. One suggestion I would make is to make one of those stock rear main cap pullers that pulls the rear cap straight up. I suggest this because there is a sequence of dry fits as you go through the installation process and the rear cap is a very snug fit. Half of the new seal stays in place when you mate the two together and then take the crank back out to put on the seal, so you cannot wiggle the unit back and forth too much. You want a starlight pull up. Chris maintains with his instructions to also follow the shop manual, and I believe the manual shows how to make that simple lifting puller dealie with a couple of screws, at least the Haynes does.
It's also in the factory TR4 workshop manual (tho not in the TR2-3 manual)
 

sp53

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I would like to point out that the Haynes manual is confusing when it talks about the installation of the felt. In one section it simply talks about putting the felt in and in another it shows how to put the felt in with a square punch with the felt cut into one inch pieces and soaked in shellac.

When I talked to Joe he was telling me a story about a professional shop that simply put the felt in dry and called it good. I guess they figured the felt would swell with oil or something. Who knows what they were thinking, but I guess they were defending there installation and blaming the new seal.
 

TR3driver

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FWIW, I feel that 1" is a little long and use the 3/4" given in the TR3 factory manual. The felt needs to be soaked thoroughly and tamped down good; if done right you wind up with shellac seeping from the joint. I've been using classic Permatex #3 "Aviation Form-a-Gasket", which seems to work well (tho it can be hard to remove the cap later on, my tool is bent!). I also use a 3/16" diameter round aluminum rod (originally part of a motorhome dump valve I believe) instead of the square drift mentioned in the manual.
 

TR3driver

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So sorry to hear about the bent tool.
No big deal. It's still functional, and only took a few minutes to make in any case. I'll use a stronger bar if I have to make another one.
 
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