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Front Timing Cover Oil Leak

  • Thread starter Thread starter onefast65
  • Start date Start date Aug 8, 2005
O

onefast65

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May 4, 2004
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#1
  • Aug 8, 2005
  • #1
I recently got my 347 up and running in my 65 fastback. Everything is great except for an oil leak that is slinging oil all over my newly painted engine compartment. I used a late model 5.0 block with a timing cover from a 70's 351w. Before I go and pull everything apart, is there anything obvious wrong with this combination? I had the shop that built the short block install the cover for me and I don't recall if there were dowels involved that would locate the cover on the block. Is it possible that there is a mis-match between these parts that is causing my problem? The oil is definitely coming from the front crank seal - it is getting onto the dampener and getting flung outwards around the engine compartment. Any help would be greatly appreciated.
 

thehueypilot

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Feb 25, 2004
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Medina,Tennessee
Aug 8, 2005
#2
  • Aug 8, 2005
  • #2
I believe there are two alignment "tubes" that go on each side of the cover to locate it. Two of the cover bolts (one on each side) pass through them. Are you running a new balancer? If not it might be worn a have a groove worn it it? Was the seal lubricated before start up. If run dry it will burn the sealing ring off. Maybe the seal was torn during installation?
 

iskwezm

10 Year Member
May 24, 2005
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Rowland Heights,California
Aug 8, 2005
#3
  • Aug 8, 2005
  • #3
probably leaking form the balancer seal,make sure there isnt a groove in the balancer,if there is they make a sleeve repair kit.
 
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onefast65

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#4
  • Aug 8, 2005
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Yes, new balancer. As mentioned, I did not do this part of the assembly. I did however find some pictures that I took during assembly that show the "tubes" in place. Maybe the seal was not lubed or damaged during assembly? Any other ideas out there?
 

Loup-garou

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Aug 11, 2001
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New Orleans, LA
Aug 8, 2005
#5
  • Aug 8, 2005
  • #5
Did the shop install an oil slinger in front of the crank timing gear? I know there are sometimes clearance issues when running a double-roller timing chain, but it does help keep oil away from that seal.
 
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onefast65

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#6
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Not sure, how would I tell if they installed the slinger?
 

tos

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Apr 27, 2001
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Cincinnati Ohio
Aug 9, 2005
#7
  • Aug 9, 2005
  • #7
They also could have installed that seal backwards.
 
C

Clark

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Rowlett,Texas
Aug 9, 2005
#8
  • Aug 9, 2005
  • #8
The slinger looks like a large washer, and has a notch to line up with the woodruff key. It would be on the crank shaft in front of the small timing gear, once the cover is removed it would be staring right at you. As mentioned before, keeps oil away from the seal and can be easily overlooked during assembly.
 

Loup-garou

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Aug 9, 2005
#9
  • Aug 9, 2005
  • #9
onefast65 said:
Not sure, how would I tell if they installed the slinger?
Click to expand...

I don't see one in that picture attached above. It's just a small sheetmetal disc that slides on the crank before the timing cover goes on.

Check the inside of the timing cover for an obvious cast-in drip rail above the crank seal area. If it has a rail, you should be okay without the oil slinger (which means your problem lies elsewhere). If no drip rail, you need to install a slinger. Be sure to measure the depth of the timing cover and compare it to the height of the timing set + oil slinger... some double-roller timing sets are too thick to allow use of the oil slinger - it causes it to hit the timing cover.

If that looks like a problem with your setup, the alternative is to find a "drip rail" timing cover.
 

thehueypilot

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Feb 25, 2004
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Medina,Tennessee
Aug 9, 2005
#10
  • Aug 9, 2005
  • #10
Another thing to look at is some metal backed seals do not have anything (Sealant) to seal between the metal case of the seal and the timing cover. If you don't put some kind of sealant between the two you could develop a leak. Just something else to consider?
 
6

66HertzClone

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Aug 24, 2004
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Central New Jersey
Aug 9, 2005
#11
  • Aug 9, 2005
  • #11
The correct procedure for installing the timing cover includes installing the balancer before tightening any bolts. This way the seal will be centered on the crankshaft. No way you say, remember those tubes? The elongated holes allow for some movement of the cover, without the balancer to center it, the cover will mount lower than it should.
 
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onefast65

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#12
  • Aug 9, 2005
  • #12
I was wondering about that - especially since the 65 mustang manual talks about using a centering tool to center things up before tightening the cover bolts. I am assuming that this means dropping the oil pan a bit to make sure that it is not pushing up on the cover before tightening the bolts.
 
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onefast65

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Aug 21, 2005
#13
  • Aug 21, 2005
  • #13
Leak Fixed - turns out that it is not a good idea to use an early 70's 351W timing cover on a 5.0 block as the dowels are at different locations. I got a 5.0 timing cover and installed as follows:

1. loosely installed cover to block with gasket and RTV and dowels on lower holes.
2. installed dampener.
3. made sure that cover was still free to move before tightening bolts.
4. installed the water pump and torqued everything down.

The result - NO LEAKS!
 
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