327 Bolt Hole question
Thread Starter
Burning Brakes
Joined: Oct 2008
Posts: 884
Likes: 1
From: Blacksburg Virginia
327 Bolt Hole question
I have a 64 327 300hp and need help identifying four bolt holes on the front of the engine block. They are in pairs one above the other on each side of the front of the block. They are located to the left and right of the harmonic balancer. The two on the passenger side had bolts in them during teardown so I put them back the two on the drivers side did not. I am getting this mystery antifreeze drip and can't find anything leaking. Today I put the tip of a power towel in each hole and the top one came back with antifreeze on it. I don't know if it has just been their from the leak or if the hole goes somehow into the cooling chamber in the block. Can anyone tell me what these holes are for and if I should plug all four?
Team Owner
Joined: Oct 2000
Posts: 38,897
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From: Washington Michigan
Those four holes have been there since 1955 - they were used originally for passenger car engine mounts, and were used later on for some accessory mountings. The top hole on the passenger side goes through into the drilled hole for the fuel pump pushrod, and should have a 3/8"-16 x 1/2" bolt in it or you'll get an oil leak from the pushrod hole. Don't use a longer bolt in that hole or you'll jam up the fuel pump pushrod.
If you have anti-freeze in that upper passenger side hole, it's a bad sign; it should only have oil in it.
If you have anti-freeze in that upper passenger side hole, it's a bad sign; it should only have oil in it.
Thread Starter
Burning Brakes
Joined: Oct 2008
Posts: 884
Likes: 1
From: Blacksburg Virginia
Those four holes have been there since 1955 - they were used originally for passenger car engine mounts, and were used later on for some accessory mountings. The top hole on the passenger side goes through into the drilled hole for the fuel pump pushrod, and should have a 3/8"-16 x 1/2" bolt in it or you'll get an oil leak from the pushrod hole. Don't use a longer bolt in that hole or you'll jam up the fuel pump pushrod.
If you have anti-freeze in that upper passenger side hole, it's a bad sign; it should only have oil in it.
If you have anti-freeze in that upper passenger side hole, it's a bad sign; it should only have oil in it.
Team Owner
Joined: Oct 2000
Posts: 38,897
Likes: 1,926
From: Washington Michigan
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