failed main oil seal
- Jim Clement
- 356 Fan
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- Tag: 1957 356 A Coupe
- Location: Calgary Alberta
failed main oil seal
I recently had my engine rebuilt, and it was tested on the test stand for about 5 hours.
so, was safe to put in the car.. but soon there after noticed a oil leak from the front center of the engine... nice clean oil..
so
pulled the engine and had the fellows find the leak.. it was the oil seal.. picture is attached.
I was wondering if anyone has an idea why it would fail like this. it almost looks like it was burnt..
it has the numbers 60 80 10 then NBR
Any ideas
so, was safe to put in the car.. but soon there after noticed a oil leak from the front center of the engine... nice clean oil..
so
pulled the engine and had the fellows find the leak.. it was the oil seal.. picture is attached.
I was wondering if anyone has an idea why it would fail like this. it almost looks like it was burnt..
it has the numbers 60 80 10 then NBR
Any ideas
- Vic Skirmants
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Re: failed main oil seal
Hard to tell from the photo, but is that the standard double-lip seal? With the outer lip un-trimmed? That will rub on the flywheel radius and get burnt, thereby causing seal failure. This has been discussed many times.
- Jim Clement
- 356 Fan
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- Tag: 1957 356 A Coupe
- Location: Calgary Alberta
Re: failed main oil seal
Vic,
I think it is a standard oil seal ? a better pic is attached.
what should have been done to it prior to installation ?
I think it is a standard oil seal ? a better pic is attached.
what should have been done to it prior to installation ?
- Vic Skirmants
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Re: failed main oil seal
That outer lip should be cut off with a sharp razor blade. I also trim the inside of the outer part. There is a metal part under the rubber, so it's easy to tell how far to cut. This puts it further into the case. Practice on the failed one.
- Jim Clement
- 356 Fan
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Re: failed main oil seal
is it the outer lip that should be cut off.. as per arrow ?
sorry for the very poor writing skills on the picture..
sorry for the very poor writing skills on the picture..
- Vic Skirmants
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Re: failed main oil seal
There are two "sealing lips". Cut off the outer one to avoid cooking it from contact with the flywheel radius.
And yes; also cut off the "lip" you show in the photo.
And yes; also cut off the "lip" you show in the photo.
- DonCichocki
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Re: failed main oil seal
Jim,
I made a fixture for my lathe so I could grind down the width of the seal to fit flush in the crankcase without altering the sealing lips. You need to get the width of the seal down to .312" (5/15"). This seal was in my engine over 24,000 miles and didn't leak. I changed it out of precaution while doing a cam swap.
I made a fixture for my lathe so I could grind down the width of the seal to fit flush in the crankcase without altering the sealing lips. You need to get the width of the seal down to .312" (5/15"). This seal was in my engine over 24,000 miles and didn't leak. I changed it out of precaution while doing a cam swap.
- Dave Wildrick
- 356 Fan
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- Location: Houston, TX
Re: failed main oil seal
Here's the outer lip that will burn if not cut off:Jim Clement wrote:is it the outer lip that should be cut off.. as per arrow ?
sorry for the very poor writing skills on the picture..
Dave Wildrick
Houston, TX
#10230
64C coupe
65C coupe
Houston, TX
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- Ron LaDow
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Re: failed main oil seal
Credit where due: Tim Berardelli advises that Wolfsburg West offers 36HP VS Viton seals, without the extra lip at $6.00, retail.
He says, and I believe him, that they are dimensionally interchangeable.
He says, and I believe him, that they are dimensionally interchangeable.
Ron LaDow
www.precisionmatters.biz
www.precisionmatters.biz
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- 356 Fan
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Re: failed main oil seal
We sell the viton rear main seal without the lip seal. Its not $6!
Just checked Wolfberg and they say its a viton seal for $6. Good thing I didn't bet the house!
ed
klasse356
Just checked Wolfberg and they say its a viton seal for $6. Good thing I didn't bet the house!
ed
klasse356
- Greg Bryan
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Re: failed main oil seal
Don - thanks for posting your findings on "thinning" the seal. I've noticed that the current seals seem to be over-flush to the case.
The two lips are a modern advance over the single lip. The area between the two lips should be filled with grease. I will try your .312 dimension next time I need to modify a seal.
The two lips are a modern advance over the single lip. The area between the two lips should be filled with grease. I will try your .312 dimension next time I need to modify a seal.
Greg Bryan
- Albert Tiedemann
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Re: failed main oil seal
DonCichocki wrote:Jim,
I made a fixture for my lathe so I could grind down the width of the seal to fit flush in the crankcase without altering the sealing lips. You need to get the width of the seal down to .312" (5/15"). This seal was in my engine over 24,000 miles and didn't leak. I changed it out of precaution while doing a cam swap.
Sometime back a poster remarked that he had found a source for an 8 mm wide seal with the other original dimensions. I am not sure if the material compositions were stated. However, a seal of this width can be installed flush to[as mentioned in the quote] or deeper into the crankcase receiving bore. In either case, and particularly the latter, the sealing lip is likely to avoid the groove, if present, worn in the flywheel hub. Other causes that promote seal failure are many and aside with non compliant seal geometry include installation skewness, sealing surface diameter and roughness and eccentricity, seal surface grooving [deeper than surface roughness], initial dryness of interface and the list is likely much longer. $6 for a single lip Viton seal is a real bargain, but I doubt that you need this newer material.
If you are tapping the seal in with an appliance or using same in support of the Factory recommended tool, Matra 204 or Zelenda US 204, take a look in the classifieds at my offering, aft-P73b to alleviate all pitfalls of the inexperienced installer. First time users get it right the first time. Square to the bore and to the right depth. With a small modification,[similar to that on the driving surface of P73] the tool will finish the seal to any depth greater above the bottom of the crankcase bore on the interval 8 < d < 10 [mm, of course]
Last edited by Albert Tiedemann on Sat Jul 01, 2017 9:34 pm, edited 1 time in total.
Albert Tiedemann, C356C
"The Hermit"
"The Hermit"
- Herlin E. Woolery
- 356 Fan
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Re: failed main oil seal
In trimming the main oil seal would that be for the T2 engine and later year engine's , thinking when i replace my flywheel , main oil seal I don't remember trimming the main oil seal in my T 1 engine and so far no oil leaks.
Albert buy having the right tool then there is no need to trim the main oil seal?
Herlin
Albert buy having the right tool then there is no need to trim the main oil seal?
Herlin
- Albert Tiedemann
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Re: failed main oil seal
Use of aft-P73b does not alleviate unwanted scenarios associated with untrimmed seals. I have used only single lip seals in the engines that I have rebuilt.Herlin E. Woolery wrote:In trimming the main oil seal would that be for the T2 engine and later year engine's , thinking when i replace my flywheel , main oil seal I don't remember trimming the main oil seal in my T 1 engine and so far no oil leaks.
Albert buy having the right tool then there is no need to trim the main oil seal?
Herlin
Albert Tiedemann, C356C
"The Hermit"
"The Hermit"
- GregVandenbussche
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Re: failed main oil seal
you can also have your flywheel machined to get the proper surface for second lip
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