Technical Timing cover seal leaking?

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Technical Timing cover seal leaking?

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Hi all,
some technical advice required before I start ripping everything apart.
I have developed what can only be described as a weeping timing cover oil seal. I know Peter recently had something similar to this but this looks different.
In my short video - sorry about the quality, you can see I am getting a spray pattern that appears to be flicked out from the front pulley.
First of all I thought it was just the fan belt as there are tiny rubber particles all over the place. My original alternator pulley was rather corroded and I sandblasted and painted it. However the inner surfaces have some pit holes that may be causing abrasion. I also re-tensioned the belt to reduce load.
This problem is still ongoing but there is definitely an oil residue being flicked out. This is on the engine side of the belt/pulley so I am presuming it is the oil seal. You can see a build up on the under shield and a sample on my finger. Although from underneath their appears to be no oil leaking and if I wipe the back of the pulley there is no oil.
Ive ordered a new alternator pulley, silicon oil seal and timing cover & sump gaskets.
I'm going to remove it all for an inspection.
Any ideas?
Also what method have you used to undo the crankshaft nut/bolt without removing the sump to wedge a bit of wood in the crank?


[ame]https://youtu.be/PwFgfTM9bG4[/ame]
 
I've had the same issue with the fan belt Sean. Little black bits of rubber everywhere. Not nice on brand new paint! Saw on one parts website a silicone rocker gasket but can't remember where now. I have a spare rocker cover if you want to try it. It's not coming out through the studs is it?
 
You can also get corrosion on the vee belt drive of the crankshaft pulley which will rip up your fan belt. As for the oil leak get a sheet of plain white paper and lodge it close under the crank pulley but not touching. Run the engine to get the splatter on the sheet. You should then be able to tell if the oil is coming from the back or front of the pulley. Either way you will not get oil drips when not running as the pulley acts as a flinger only with the oil under pressure. If the oil comes from the pulley back you know it is the timing chain cover seal, from the front it will be the oil filter seal.
 
ImageUploadedByFIAT Forum1463913992.437249.jpgImageUploadedByFIAT Forum1463914011.567662.jpgImageUploadedByFIAT Forum1463914028.000707.jpg
I took the engine under tray off and there is definitely evidence of oil coming from the crankshaft front seal. Made a bar with 2 holes to mount to the front pulley using 2 of the 6mm bolts and was unable to undo the pulley bolt.
On removal of the pulley, the seal looks ok but there is a slight line/groove around the pulley machined surface. This could be enough to cause the leak. Although I can't actually feel anything with my finger nail.
So maybe I will see if I have a better pulley and try that before changing the seal?
 
I've had the same issue with the fan belt Sean. Little black bits of rubber everywhere. Not nice on brand new paint! Saw on one parts website a silicone rocker gasket but can't remember where now. I have a spare rocker cover if you want to try it. It's not coming out through the studs is it?


Cheers Damian, but it's not the rocker cover, it's the front timing chain cover.
 
You can also get corrosion on the vee belt drive of the crankshaft pulley which will rip up your fan belt. As for the oil leak get a sheet of plain white paper and lodge it close under the crank pulley but not touching. Run the engine to get the splatter on the sheet. You should then be able to tell if the oil is coming from the back or front of the pulley. Either way you will not get oil drips when not running as the pulley acts as a flinger only with the oil under pressure. If the oil comes from the pulley back you know it is the timing chain cover seal, from the front it will be the oil filter seal.


Most definitely the oil seal. Both pulleys look ok with regards to the v belt, maybe it's just bedding in or cheap quality belt? Could also be due to the oil contamination?
 
So I decided rather than remove the timing cover that has no leaks from the gasket & a new front seal with less than 10 miles use, I would try and deal with the culprit in question.
Presuming that the seal must be sitting on the groove in the pulley and thus causing the leak, then the best thing to do is remove the groove.
There's about 2mm difference in the 2 diameters so I thought I have enough to play with.
With a piece of 180 grit paper I slowly sanded around the circumference until the groove disappeared.
Fitted it all back together & removed any oil residue with some degreaser.
Started it up and run it for 10-15 minutes at above idle using the handy cruise control.
Initially there was a little splatter of the remaining oil but then it cleared.
Tried the white paper test and all seams fine. So it's going back together and give it another try.
 
Sean,

I just replaced this seal (again) last week.

Since you're getting oil that's flung off from the pulley, it would appear to be coming from the pulley-seal interface. If the leak was coming from the seal-timing chain cover interface, the oil, theoretically, would just drip down the face of the cover.

Hopefully, you've got it sorted.

But if you end up replacing the seal, this is a FWIW: I had replaced both crankshaft seals with the silicone ones. In short order, the seal at the flywheel end started leaking, so I pulled the engine back out to replace that one. Was careful to not damage the seals when reassembling, but a few hundred miles later, the crankshaft seal on the timing side went from weeping to leaving drops of oil in the driveway very quickly. It may be just me, but I didn't have good luck with the silicone seals. This time around, I purchased locally and got one that also has a dust lip to keep debris away from the seal. I also used a reassembly lube so the seal wouldn't run dry until the oil found its way there.

While there was very little oil leaking, I wish I had tackled it earlier because the pulley did a great job of flinging a film of oil all over everything in the engine bay. It took me longer to clean the bay than to replace the seal.

I also had a groove on the pulley. Much deeper than yours. But since the new seal rides on a different place on the pulley, I left it.
 
PS. I read that some seals, which have PTFE in them shouldn't be pre-lubricated. Isn't the world complicated??

Not that complicated if you compare a 500 to a 60 year old LandRover.

LandRovers leaked from new, so I don't worry if my 43 year old Fiat drips occasionally:)

Life is too short, just drive it and enjoy it, a gravel drive does help, does not show the drips.

H A
 
Life is too short, just drive it and enjoy it, a gravel drive does help, does not show the drips.

H A

Agreed on all points and given that I have about 150 square metres of building site style parking, drips don't actually matter anyway. I spilled 4 litres of used diesel engine oil the other week without fretting.
I don't stress about stone-chips, rusty chrome or the finish of aluminium parts, but for me, mechanical issues are always worth chasing.
That's because I do drive my little cherub so much and so far.:)
It is possible to eliminate Fiat 500 oil leaks and it feels good to have done it; but my life is shorter now.!!!?
 
With a piece of 180 grit paper I slowly sanded around the circumference until the groove disappeared.

Did this work Sean Franko500?
When I reassembled the 650 I substituted with silicone seals. I was very, very careful in fitting and aligning it but it has wept oil since day one; very little but enough to annoy me greatly.
I have spare pulleys and a particularly good one from the 594 engine.
If your fix worked I might just swap the pulley as a first attempt.
 
Yep it worked fine. Not a drop of oil from the pulley seal.
My D one also had a deep groove. Unfortunately the D pulley is different to the later one and not so easy to replace. So my Dad has machined it down on the lathe. There's a fair amount of metal left on the diameter to still provide a good seal though.
 
You have got a very talented and useful dad Sean; obvously a family trait. :)

On stripping down the pulley I found that it has no wear perceptible to my fingertip but that the seal looked very deep in the housing; so I wondered had I made a mistake or was the silicone seal made to a different depth?
Checking against cover of the 594 engine it is obvious that the housing is different. ((594 on the right). It's almost like you could fit a deeper seal or possibly two seals.:eek:
MAL_0084 by Peter Thompson, on Flickr
The pulley wheel also has an extra machined surface on it. (on the left).
MAL_0085 by Peter Thompson, on Flickr
So although the existing seal looked good I changed plans and did what I hope is the sensible thing, and replaced the seal with a standard one. I am hoping that this brings the lip to bear on a different "land" on the pulley and that the standard seal will have a tighter grip on the shaft.
It is a point to note that these apparently identical components, both made for the 126-type engine, although admittedly 12 years apart and in different countries, may not be directly interchangeable.
 
The pulley on the left has a machined face, however it should not be touching anything. As you know from taking it apart/putting it together the pulley can only go on so far and is clamped between the crankshaft and the large bolt/washer. So its just the diameter and depth that is crucial.
It wouldn't hurt to run some emery paper/ fine sand paper around the journal of the pulley to make sure there is no wear as the seal will find it.
Hopefully a new seal will sort it - they are usual pushed all the way home in the casing.
 
Back in a previous life I was a diesel mechanic. We used to work on all the old crap that the big guys and dealers didn't want too.

Weeping seals and worn shafts were a common issue, and while the customer usually mind spending money on their gear, buying a new crankshaft to sort a small leak was out of the question.

Turning down the shaft works, but you are reducing the diameter and hence the "squish" of the seal on the shaft surface. Most seals can tolerate a bit of this, but the pressure they will leak at is reduced.

I used to blend out the damage on the lathe with a bit of emery tape and then fit a speedi sleeve. They are a very thin, hard steel sleeve that fits over the damaged area and gives the seal a smooth, flat surface to run on. I usually loctited them on, just because I am anal that way. There are many manufacturers of these, but SKF do good ones. I am not sure if one would be available for the Fiat pulley but it is worth a shot.

http://www.skf.com/us/products/seal...leeve/installing-skf-speedi-sleeve/index.html

Let us know how you get on.
Chris
 
Chris, I didn't know such a simple and brilliant think existed.
My leak didn't seem to be because of any wear or damage and the pulley wearing surface looked excellent.
So I've reassembled and will do a test drive tomorrow and then report back.
 
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