Birf soup - using Marlin axle seals...confused! (1 Viewer)

[FirstToy]

Ali,
did you carefully check the face of the rubber seal? I remember some people using the seating tool that wwas not wide enough and cutting the face. You can probably only see if if you tug on it.

Otherwise,
I noticed the Marlin seal rubber was not as flexible but seemed a much beefier design than OEM.
The outside of the seal (that faces the axle) has a thin, orange/red seal. Maybe that seal is not thick enough and caused some leakage?

bummer you had to tear down

 

[Tools R Us]

I like the Marlin type for the earlier rigs, but prefer the flexibility of the stock one on the '80. My thoughts in this post:
IH8MUD Forum - View Single Post - Marlin Crawler inner oil seals and installation tool

I have had a few apart and have put stock type back in, so haven't run the Marlin seals in an '80, have in earlier type axles.

 

[alia176]

Ali,
did you carefully check the face of the rubber seal? I remember some people using the seating tool that wwas not wide enough and cutting the face. You can probably only see if if you tug on it.

Otherwise,
I noticed the Marlin seal rubber was not as flexible but seemed a much beefier design than OEM.
The outside of the seal (that faces the axle) has a thin, orange/red seal. Maybe that seal is not thick enough and caused some leakage?

bummer you had to tear down

Good points. However the face is good in this case. The thin orange seal that goes on the outside of the flange did move. Another words, when you tap in the seal into the axle housing, this super thin raised sealant (for lack of a better word) lifts off and moves to the back. I'll try to take a pic to help illustrate.

However, there is no way that gear oil escaped from the interface of the metal flange and the axle housing. This is simply too good of a fit IMO to allow leakage.

I like the Marlin type for the earlier rigs, but prefer the flexibility of the stock one on the '80. My thoughts in this post:
IH8MUD Forum - View Single Post - Marlin Crawler inner oil seals and installation tool

I have had a few apart and have put stock type back in, so haven't run the Marlin seals in an '80, have in earlier type axles.

Your assessment seems accurate, as always. This is a beefy seal but less flexible and for a full time rig *may* not be the perfect thing.

That notch you see on the rim (first pic) is from my seal puller tool.

 

[alia176]

More pis for your amusement....

 

[alia176]

Further testing in my U.L. approved lab revealed the following:

flexing the OEM seal is super easy as has been mentioned already. Flexing the Marlin is difficult. However, if you remove the round spring out of this seal, then it became more flexible.

Yes, I did pinch my finger tip in a pinch point

 

[alia176]

More testing....

The OEM unit uses a coil spring that can stretch whereas the Marlin uses a simple wire loop that is open and can also stretch to a point. However, the oem spring is more sexy flexy by far.

At least that's according to my super calibrated fingers anyway...

 

[alia176]

This is the argument CruiserDan made as well when I told him I was going to try the Marlin seals out.

I'll be going back in next month for a regear and will see the results.

Since you're primarily rear wd, I have a feeling that yours will be in good shape.

 

[desertdude]

Makes sense looking at the build of the seal - So what is the word from Marlin?

btw - Keep that hammer away from your fingers

 

[alia176]

I get the feeling that Marlin hasn't received any feedback on this particular seal from 80 owners. Nicholas from Marlin wasn't able to figure out what's going on either and as you know, troubleshooting over the phone w/o seeing the issue in person is rather difficult.

I'd like to hear some feedback from other Marlin seal owners to get a bigger picture.

 

[Cruiserdrew]

I'm running 3 sets of Marlin seals and 1 set of the OEM seals (on my 80). I think in a part time truck the speed and ease of the Marlin seal installation is worth deviating from OEM. However in a full time truck I have a feeling the OEM can "follow" the sealing surface better.

Ali-you don't have groves in the axle seal surface do you? I think once those grooves develop, the Marlin will likely seal better, since the lips of the seal ride in a different place.

 

[alia176]

No grooves on my axle that i can tell.

Edit: the area where the seal rides is *slightly* lower than the rest of the material. Is this a groove? Yeah, I guess you could call it that.

 

[Tools R Us]

... The thin orange seal that goes on the outside of the flange did move. Another words, when you tap in the seal into the axle housing, this super thin raised sealant (for lack of a better word) lifts off and moves to the back. I'll try to take a pic to help illustrate.
...

That is how the seal ring works. It's bigger than necessary, so the majority is sacrificed, the film that stays in place does the sealing. You can easily do the same thing with any seal; clean the surfaces oil residue free and apply a skin coat of silicone type sealer before driving the seal. In this case it doesn’t matter, the slight amount that weeps around the outside if the seal is irrelevant.

...
flexing the OEM seal is super easy as has been mentioned already. Flexing the Marlin is difficult. However, if you remove the round spring out of this seal, then it became more flexible.
...

The seal isn’t a bushing, it’s job isn’t to support the axle, so should be as soft as necessary to seal. The axle doesn’t run concentric, has play in it’s mounting, steering, etc, allows it to move slightly. Try putting them on the axle, push on the side of the seal to simulate axle deflection. My guess is the stock seal will maintain better contact with the axle, seal better?

No grooves on my axle that i can tell.

Edit: the area where the seal rides is *slightly* lower than the rest of the material. Is this a groove? Yeah, I guess you could call it that.

From what I can see in the pic, that axle looks good, I would run it. If you have access to a lathe, you can spin it up and clean up/polish with some emery cloth, but IMHO not necessary.

 

[locrwln1]

Nice comparison between the two seals. Like Ali, I too have Marlin's and I'm getting some seepage on the passenger side (long side). I am approaching 30k on mine. Not happy about that. Guess I will be going back to stock seals.

Jack

 

[Romer]

Interesting discussion. Lots of points I had not thought of. Thanks Ali for bringing this up.

 

[1973Guppie]

so is the consesus that 80 owners should use the OEM seals? I am going to be doing a full rebuild here soon and don't want to have to go back in, that is for sure.

 

[arndog123]

Nice to know because I'll be doing front axle service on both 80's in the near future.

 

[alia176]

Given the info learned from this thread, I put back in a new OEM seal and will need to get another one for the other side.

Interestingly enough, the Marlin seal installer tool is perfect for installing an OEM seal! As you see from the pics, I use lots of grease on the spring side of the seal to prevent the spring from popping out during insertion (hammer tapping). Be sure to lube up the seal installer with gear oil or light grease before sliding on the OEM seal. And as always, lube your shaft before insertion

 

[edog's 80]

It's mostly anecdotal since I didn't take pics, but I am running the Marlin seals and I think I had the same problem. I tore into mine to put new birfs in only a few thousand after my recent rebuild and the grease definitely had some oil in it. FYI I am also running extended diff breathers.

 

[timer00]

after reading all this I wish I would have just put the stock seals in instead of thinking I was upgrading using the Marlins haha

 

[Ebag333]

The seal isn’t a bushing, it’s job isn’t to support the axle, so should be as soft as necessary to seal. The axle doesn’t run concentric, has play in it’s mounting, steering, etc, allows it to move slightly. Try putting them on the axle, push on the side of the seal to simulate axle deflection. My guess is the stock seal will maintain better contact with the axle, seal better?

I'd be curious to see someone compare them side by side.

I found this little blurb in Marlin Crawler's forums.

Here we show why the new Marlin Crawler Heavy Duty Inner Axle Seal is so innovative.

Deflection required for Air Gap		
Common Aftermarket Seal     	Marlin Crawler HD Seal
0.022" / 0.56mm			0.058" / 1.48mm

Here we see our HD Seal pushed 0.050", just before an air gap is formed:

And here is the common aftermarket seal pushed out 0.050", the same distance that our HD Seal still seals as seen above:

Here we see our HD Seal pushed 0.058" where an Air Gap is formed:

Now comes the real shocker!
Here is the common aftermarket seal SITTING AT REST.
The weight of the axle causes an air gap to form without any external forces!!

So this commonly used seal can't even support the weight of the axle it is supposed to be sealing! I know this is not necessarily a design criteria of a seal, but since the birfeld and inner axle vibrate and deflect, it is awesome to know that the Effective Sealing Distance of the Marlin Crawler Heavy Duty Inner Axle Seal is an astonishing 164% greater than the common aftermarket seals!

I think we can all agree that the OEM seal is going to do better than the aftermarket...but the question is, how much better? Considering the aftermarket is the same design, I'd be extremely curious to see how they compare.