Leaking plug on rear of 200ci from 1966 Mustang

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BobSled
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Leaking plug on rear of 200ci from 1966 Mustang

Post #1 by BobSled » Wed Oct 10, 2018 1:17 am

Hi,

I'm new to engine repairs and was replacing the clutch in my 1966 Mustang 200ci engine, and I noticed what looks like a leak from a freeze plug on the rear of the engine. I cleaned it off and waited a few hours, and another few drops formed (engine not running since the crankshaft, starter, etc.is removed). I figured it was a freeze plug and that it might be leaking antifreeze, but it sure looks/feels like engine oil.

See pictures.
Back of 1966 Ford Mustang Engine.pdf

Dorman_Plug_from_Mustang.pdf


1. Can someone tell me what the plug is?
2. It looks like it is stamped "Dorman Products" and "D-48-C" (or "P-48-C") but I can't find that part online. Suggestions for a replacement part?

Thanks,
BobSled
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B RON CO
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Re: Leaking plug on rear of 200ci from 1966 Mustang

Post #2 by B RON CO » Wed Oct 10, 2018 7:02 am

Hi, that plug is the back of the cam bore. That is why it is dripping oil. Good luck
B RON CO. Still workin' on it!

1933 Ford Pickup - 59A Flathead V8
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bubba22349
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Re: Leaking plug on rear of 200ci from 1966 Mustang

Post #3 by bubba22349 » Wed Oct 10, 2018 8:10 am

X2 it's the cam plug along with the smal pipe plug above it for the Hydrolic Lifter oil galley and yes these would only leak engine oil. The other upper center soft / freeze plug (above the crankshaft) seals the cooling system passage. The cam plug you have circled in red are replaced with a standard steel soft plug (ask for the size of the cam bores opening) the receiving bore needs to be clean and a good sealer applied before the soft plug is installed. When this plug is installed and sealed correctly it will last the life of engine until the next rebuild. By the way be sure to use some sealer on the crankshaft bolts too or they can also leak some oil. Good luck :thumbup: :nod:
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Re: Leaking plug on rear of 200ci from 1966 Mustang

Post #4 by fakundo__92 » Wed Oct 10, 2018 8:13 am

Hi. The water cap is behind the cylinder head. I had to remove it to replace it. After the clutch there is one of oil.

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Re: Leaking plug on rear of 200ci from 1966 Mustang

Post #5 by CZLN6 » Wed Oct 10, 2018 1:02 pm

Howdy Bobsled:

Be sure to install a new soft plug in the cam access hole. Many have mistaken a slow oil leak at the back of the engine for a rear main seal. Fixed the rear main seal only to find they still have a leak from the rear of the engine. You can give yourself an "Atta boy" for spotting the leak while the back end was apart. You saved yourself some headaches.

Good Luck.

Adios, David
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http://www.falcon6handbook.com/

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Re: Leaking plug on rear of 200ci from 1966 Mustang

Post #6 by BobSled » Wed Oct 10, 2018 10:20 pm

You guys are AWESOME!! Thanks very much!
BobSled

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