TheSamba.com :: View topic - Oil Slinger-What It Is, What Can Happen, and How To Fix It.

Sat Oct 04, 2014 8:20 am

I've seen several folks comment that the part is not a slinger. I actually agree that the term 'slinger' usually refers to a part of a shaft or a part on a shaft that rotates with the shaft. That said, I'm not sure what would be a better and more recognizable term for this part of the bell housing. The riffles on the inside coupled with the rotation of the shaft 'sling' the oil away from the seal. If someone wants to come up with a more appropriate and more recognizable name for that part, I'll be happy to change the term I use. Until then, I will continue to use the term 'oil slinger' despite it being a bit of a misnomer.

I see the term 'intercooler' bandied around despite ther only ever being a single charging device installed. I even use the term 'intercooler' despite it being a misnomer because most folks know what is being talked about despite it being technically incorrect. 'Moot' also doesn't mean 'irrelevant', 'whom' should be used in the accusative case and the nominative case should follow the verb 'to be'... "Are these they?"...

Sat Oct 04, 2014 8:33 am

I also clew the "slinger" with fluid metal when its loose.
Very important is not to fix the clutch shaft to the end. The shaft has to move. If it is screwed to the end without moving the pilot bearing will be destroyed quickly.

Sat Oct 04, 2014 8:54 am

1vw4x4 wrote: Some of these replies with making tool to install the seal, and welding
the (so called) slinger are really over kill. I've repaired a dozen of these.
I thought I was the only one finding this, because many clutches are being replaced, but the pilot bearing is not. This rips up the input shaft seal
and gear oil soaks the new clutch. Then the owner sells it. I get it for repairs and find the new clutch disc with everything else bad, and no gear oil
in the transaxle. A complete clutch job at this stage is over $1000.00. I just did one.
Its not a slinger. A slinger is a rotating part (usually on a shaft) that
throws the oil by centrifugal force. This does not rotate, although it does help
throw the gear oil back into the transaxle.

It's a "rifled input shaft support bushing". Call it whatever, we know what you're taking about :)

Rifling is likely not needed in this situation for anyone looking into building better bushings. Some of the pics have pretty scarred stuff that I'd not bother putting back in.

Sun Oct 05, 2014 7:16 pm

The input shaft should not contact the slinger or any alternative bushing and IMO if you don't have the rifling inside the bore it would likely be better to just leave the insert out entirely than to add an un-rifled bushing. The un-rifled bushing would do nothing other than get in the way of oil returning to the trans from the seal area. Maybe drill a tiny hole at the low point of the seal bore to let fluid drain from the seal as typical in many other applications.

Sun Apr 12, 2015 11:49 am

I am really interested in this thread, but the pictures don't show. Have you moved them? Please help, thanks!

Andrew A. Libby wrote:

The awl in the following picture is pointing to the slinger:

Sun Apr 12, 2015 2:36 pm

Not the same exact pics, but basically the oil slinger is here:

...which is behind the input shaft seal:

...which is behind the t/b guide:

FWIW, these are all from the Samba gallery, so they should be safe here...

PS: Anyone know anything about Andrew's pics? ...lost forever, or...???

Mon Jan 18, 2016 7:34 pm

Thanks for posting this. I happened to be at the input side of transmission of my syncro looking for things to fix when I stumbled upon this. My slinger seems firmly in place and pilot bearing hasn't failed but I wonder what is life span of the pilot bearing?
What does this felt piece look like I don't see one here? Has someone made anything better other then sealed pilot bearing?

Sat Mar 12, 2016 3:43 pm

Excellent info here. I do wish Mr. Libby's pics were visible. I'm not looking forward to diving in to this...

Sat Jul 30, 2016 6:29 pm

Earlier today I was replacing the the clutch on my '85 gl. This being my first time having the trans out on a vanagon, I just planned on replacing the input shaft seal and rear main seal. The input shaft seal was wrong. Annoyed, I left the trans out to wait for the correct one. Now I'm reading this and thinking this may have been a good thing. I'll be checking it when I get back. Thanks.

Mon Feb 27, 2017 1:08 pm

Engineering talk would call the part an "oil return thread". Most everyone that has worked on vans before 1972 model year and all air cooled bugs will be familiar with this as it used on the crankshaft pulley.
Only difference is, on the pulley the thread turns, and on the transaxle the shaft turns. The oil does not care about this and is happy to be 'screwed' back to where it belongs.
One other cause of the needle pilot bearing to wear out/fail is "riding the clutch". Whenever the clutch pedal is pushed down, even part way, there is relative motion between the crankshaft and the transaxle input shaft. Hence the pilot bearing is turning. When the clutch is fully engaged, foot off the pedal, there is no motion and the bearing will probably last forever.
Where this can go wrong is drivers that come to a stop sign or red light and wait with the trans in gear and the clutch pedal pushed down. Then the pilot bearing is spinning the whole time. This will wear that bearing out much quicker than waiting in neutral.
When I was working on these full time, whenever the engine or trans was out the pilot bearing was inspected. If it was found good it was lubed with bearing grease and the felt 'seal' that fits in the flywhl was checked to make sure it was there.
Whenever a clutch was replaced pilot bearing was also changed. Old one can be removed by filling end of crank with thick grease and tapping close fitting shaft into bearing. Bearing will pop right out or add more grease.
I used an old input shaft.
Also I have seen quite a few of the pilot bearings completely destroyed with the needles falling out and rusty. Worst case is the needles jam around the input shaft then clutch does not matter because shaft is stuck to crank. Very hard to drive or shift.
When the bearing is this bad a rotary tool can be used to grind away part of the outer race in the crank. Then the bearing will come out as there is no more press fit.

Mon Mar 25, 2019 2:08 pm

It's a pity those pics no longer exist, but anyway I will certainly check this out once there.... thanks!

?Waldo? wrote: A "soapbox" I've been preaching from for a while now is "always check the oil slinger before installing a tranny". After coming across another premature failure, this one less than 18 months after a very prominent, and expensive shop "fixed" the whole clutch system (after a seemingly catastrophic failure), I feel like perhaps a pictorial would be helpful. It is a seemingly inconsequential part and yet can cause an incredible amount of expense in both labor and materials and often does.

The awl in the following picture is pointing to the slinger:

The input shaft oil slinger is a metal sleeve that resides behind the input shaft seal in the transmission. It has a spiral flute or thread on it's inner surface. It should be a press fit into the bell housing. It's purpose is to "sling" tranny fluid away from the input shaft seal and extend it's life. It does so in the following manner. The input shaft, while spinning, gets the tranny fluid to spin around it. The flute of the slinger is oriented so that with the clockwise rotation of engine and input shaft, the spinning motion of the tranny fluid, forces the fluid away from the seal. Quite ingenious really.

What goes wrong is that on occasion the slinger becomes loosened from it's press fit in the bell housing. This is most often caused by a failure of the pilot bearing in the end of the crankshaft. The failure of the pilot bearing allows the input shaft to flop around excessively. In turn, the flopping input shaft hits the slinger and in short order frees it from it's press fit. As an aside, I feel the premature failure of pilot bearings is quite frequently caused by the removal of the felt ring in the flywheel which prevents the clutch dust from ruining the pilot bearing rollers. Although, the pilot bearing might be fine, I always check the slinger as the last mechanic to install the pilot bearing might not have.

Once the slinger is no longer a press fit in the bell housing, it is no longer a help, but rather a cause of destruction. The flute of the slinger is oriented such that once it is no longer held in the bell housing, the tranny fluid, instead of being slug away from the seal, now actually spins the slinger and throws it AT the seal, chewing up the back of it. Once the input shaft seal is sufficiently chewed, it will leak tranny lube, often significantly. I have actually seen where it got on the clutch and actually caused (coupled with stupid driving techniques) the explosion of the clutch disc.

I ALWAYS CHECK THE SLINGER IN THE BELL HOUSING PRIOR TO INSTALLING A TRANSMISSION!! YOU SHOULD TOO!!

That's worth repeating.

I ALWAYS CHECK THE SLINGER IN THE BELL HOUSING PRIOR TO INSTALLING A TRANSMISSION!! YOU SHOULD TOO!!

The check is simple. Remove the input shaft seal (a seal puller or sheet metal screws and a couple pry bars are good methods, IMO) and use a small pic or eyeglasses screwdriver to pry on the slinger. If it moves, IT MUST BE ADDRESSED to avoid significant costs in parts and labor in the very near future.

To address the failure, I remove the bell housing from the transmission (6 bolts in the clutch housing area and 4 below m8 - 13mm heads), I remove the slinger, peen the surface that should hold it so that the press fit is restored, clean the various surfaces with brake cleaner and JBWeld it in place. I feel that the combination of the JBWeld and peens is a permanent fix.

Here is the surface that needs to be peened:

Use a punch to make dimples. Although the dimples depress the metal further, the edges of the dimples cause the metal to raise and will grip the slinger.

Here is a picture of the surface after being peened:

After I'm convinced the press fit is restored, I mix up some JBWeld, slather it on the peened surface and the face that is in the direction of the flywheel and hammer in the slinger. Once the gasket surface is cleaned thoroughly and the JBWeld has set up, then the bell housing can be installed on the transmission. I use a very thin coating of Permatex on both the tranny and bell housing mating surfaces and torque them together.

Here's one shot on the tranny side:

And here's one on the clutch side:

I would add that this is a VERY COMMON failure. Probably half of the transmissions I've removed have had a flopping slinger accompanied with a leaky input shaft seal.

Once more just for good measure:

I ALWAYS CHECK THE SLINGER IN THE BELL HOUSING PRIOR TO INSTALLING A TRANSMISSION!! YOU SHOULD TOO!!

Andrew

Mon Mar 25, 2019 2:38 pm

More recently I found that oversize replacements are available here: https://www.vw-t3-bus-shop.de/en/shaft-bushing-clu...production

Mon Mar 25, 2019 2:43 pm

?Waldo? wrote: More recently I found that oversize replacements are available here: https://www.vw-t3-bus-shop.de/en/shaft-bushing-clu...production

I guess I could find (look for) these on my 3 spare DMs?

Tue Mar 26, 2019 12:18 pm

?Waldo? wrote: https://www.vw-t3-bus-shop.de/en/shaft-bushing-clu...production

Is that a link to an "oil slinger"? ^^^

Can I locate them on these boxes?

Tue Mar 26, 2019 12:22 pm

No, that is the thowout bearing guide tube. Behind the guide tube and the seal that is behind the guide tube is where the slinger resides. It pokes into the inside of the transmission. It's easiest to see with the bell housing removed.

Tue Mar 26, 2019 12:31 pm

Aha, OK, so that is another good reason to remove the bellhousing on the bench - I can check out these slingers......

Thu Jul 02, 2020 11:46 pm

Hi Guys,

Here in the UK, I couldn't find any information on the oil slinger and nobody seemed to know anything about it, so with only one supplier stocking replacements, finding this fantastic post was a Godsend!

Although I reckon it's the through hole in the bell housing that has worn, I have a new slinger on order, though I think my real problem stems from the pilot bearing. It has totally disintegrated leaving just the outer race in the crank end and a 'smear' on the end of the input shaft.

What do you think could have caused this failure and what damage should I be worried about in the transmission?

Regards,
Grant

Fri Jul 03, 2020 6:25 am

^^^ Typical failure mode, all for want of grease...

- Dave

Fri Jul 03, 2020 4:39 pm

Happened to me when the pilot bearing spun out. Take a close look at the tip of the input shaft, and look in the flywheel center with a flashlight or borescope.

Fri Jul 03, 2020 5:49 pm

unclegee wrote: What do you think could have caused this failure and what damage should I be worried about in the transmission?

If you have a gasser, was the felt ring installed properly in the flywheel? If not, then the chain of events was likely that dust from the clutch friction surfaces got into the pilot bearing and caused it to fail prematurely, etc, etc...

You should worry about the slinger, the input shaft seal, and the end of the input shaft.