Oil leak


charger440

GT Owner
Mar 5, 2006
46
Duluth, Georgia
I am replacing the oil pump belt, and discovered that I have a small oil leak inside the oil pump belt cover. Minor, but enough that the turbulence from the belt throws the small amount of oil around and makes the belt oily. It is hard to determine where the oil is coming from, but the seal looks dry, while the inside of the gear is wet and the two bolts heads inside the cover have oil drips on them. Any thoughts on the likely leak source, and how to fix it, are greatly appreciated.
 

GT@50

GT Owner
Dec 14, 2019
231
Issaquah
flex seal.jpg
 

gtjoey

Keep Smiling - GT Owner
Mark IV Lifetime
Oct 14, 2005
3,438
When these cars SIT the front pump seal dries out....Easiest way is put a new pump.
Common way back in the day about 2 years out from NEW.....
GTJOEY1314
 

GT101

*UK Support*
Supporting Vendor
Jan 20, 2010
305
Colchester, Essex, UK
You can replace just the seals - they're not serviced by Ford as separate items but are a relatively common size.
My scribbled notes suggest they're 28 x 50 x 8 double lipped nitrile seals - less than $5
Most bearing and seal shops should be able to get them if they're not on the shelf.
 
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charger440

GT Owner
Mar 5, 2006
46
Duluth, Georgia
Thanks for the good advice. I find the original Ford oil pump (4G7Z-6600-AA) for $ 1,523, and the Melling oil pump (M360) for $ 98. Would the Melling oil pump be OK? (it is listed as standard pressure, standard volume, aluminum body).
 

charger440

GT Owner
Mar 5, 2006
46
Duluth, Georgia
So I went ahead and bought a new oil pump to solve the small oil leak inside the oil pump belt cover. Turned out that I received what I assume to be the internal oil pump (?), and not the outer one behind the belt. What is the outside one called? Oil sump pump maybe? A good source for this part?
 

GTMD

GT Owner
Mark II Lifetime
Jan 4, 2011
763
NorCal
I didn't think there was an internal oil pump since this is a dry sump system. Only the external pump. Are you sure it was for a GT and not a Mustang?
 

charger440

GT Owner
Mar 5, 2006
46
Duluth, Georgia
It was a Melling oil pump M360, application listed for both the 07-12 GT500 and for the 05-06 GT with dry sump (see first link below). I did find the external oil pump from a Ford OEM parts vendor (see second link below). But at that price I will first try to find the correct seal and replace it.


 

CanadaGT

GT Owner
Sep 28, 2006
180
Edmonton Alberta
I worked on one that was leaking and the chamfer on the taper of the pulley was off. Put a spacer washer to suck the pulley tight, it did the trick. I believe the threads for the nut were not deep enough and the nut was bottoming out on torque spec. Hence the spacer (Hardened Chrome washer from my Harley days) Anyway it still is not leaking at his service this year. My $.02
 
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