1956 leaking oil through threaded bolt holes

[Marie]

We just bought a 56' Thunderbird. 312 motor. Its bleeding oil. We found two threaded holes in the back of the motor. I can see the push rods moving when the motor is going. Obviously that's where the oil is coming from. My question is...can anyone tell us what they are for? Should we just put grub screws in to bung them up?

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[1957Bird]

Wow that don’t sound right
Think you might want to be a bit more specific about where the holes are.
both I’m one side?
One on each side?
Top of the engine, back of the engine???

 

[jack-in-sac]

We just bought a 56' Thunderbird. 312 motor. Its bleeding oil. We found two threaded holes in the back of the motor. I can see the push rods moving when the motor is going. Obviously that's where the oil is coming from. My question is...can anyone tell us what they are for? Should we just put grub screws in to bung them up?

Where; "in the back of the motor" are these threaded holes specifically located?

 

[55birdman]

Pictures?

 

[Tater Salad]

Y

This courtesy of John Mummert. Scroll down about half way, to the section on intake bolts. Or read the whole write up.

First picture is passenger side, I have a short bolt just plugging the hole. Second picture is block grounded to firewall.
See if the holes in the pictures are the holes you're questioning.

The link at the top of my post is just the letter "Y". Click it to read John's article.

 

[Marie]

Where; "in the back of the motor" are these threaded holes specifically located?

Sorry. They are in the top of the heads. One by the breather on the drivers side. The other behind the distributor on the passenger side

Y

This courtesy of John Mummert. Scroll down about half way, to the section on intake bolts. Or read the whole write up.

First picture is passenger side, I have a short bolt just plugging the hole. Second picture is block grounded to firewall.
See if the holes in the pictures are the holes you're questioning.

The link at the top of my post is just the letter "Y". Click it to read John's article.

Hi. Yes these are the holes. We can see the push rods moving when the motor is running. Do you think that this would explain us losing approx 1 pint of oil per 100 miles? Can you tell us what the holes are actually for? Do we need that earth strap on the firewall?

 

[Marie]

In the top of the head. I by the breather and on the other side one is directly behind the distributor

I was wrong about 1 being by the breather, it's by the temp sensor. Both holes are just below the tappet covers. Someone put two photos up and Kev said those are them

 

[doug7740]

We just bought a 56' Thunderbird. 312 motor. Its bleeding oil. We found two threaded holes in the back of the motor. I can see the push rods moving when the motor is going. Obviously that's where the oil is coming from. My question is...can anyone tell us what they are for? Should we just put grub screws in to bung them up?

To answer your question, the threaded hole on the back of the left cylinder head is for the engine to firewall ground cable. (See attached picture) The threaded hole on the back of the right cylinder head is for the ignition wire bracket. (See attached picture)

A thread sealant is a must for any bolts or studs that extend into engine block or cylinder heads that do not have a blind hole. I place a dab of blue Loctite on each bolt before installation.

doug7740
1955 Thunderbird Blue

 

[Marie]

To answer your question, the threaded hole on the back of the left cylinder head is for the engine to firewall ground cable. (See attached picture) The threaded hole on the back of the right cylinder head is for the ignition wire bracket. (See attached picture)

A thread sealant is a must for any bolts or studs that extend into engine block or cylinder heads that do not have a blind hole. I place a dab of blue Loctite on each bolt before installation.

doug7740
1955 Thunderbird Blue

That's amazing. Thank you so much. We knew something was missing, just didnt know what. We'll get onto sorting that out now. Thanks again. So glad I joined up here.

To answer your question, the threaded hole on the back of the left cylinder head is for the engine to firewall ground cable. (See attached picture) The threaded hole on the back of the right cylinder head is for the ignition wire bracket. (See attached picture)

A thread sealant is a must for any bolts or studs that extend into engine block or cylinder heads that do not have a blind hole. I place a dab of blue Loctite on each bolt before installation.

doug7740
1955 Thunderbird Blue

Sorry to be a pain but we just bought this car. On the way home were losing approx 1 pint of oil per 100 miles. Do you think we could be losing that much oil out those holes and running down the back of the motor. Its supposed to have been rebuilt so hoping the main seal was done.

 

[doug7740]

If there are no bolts in either of the holes, it is possible that is where your oil leak is originating from. Replace the missing bolts and put a dab of blue Loctite on each bolt before installation. Make sure the bolts that you use are not too long. Since you can see the push rods through the bolt hole, you don't want the bolt to contact the push rod when you tighten it up.

doug7740
1955 Thunderbird Blue

 

[Marie]

Just letting you all know that we put bolts into the holes but still losing oil. Main rear seal leaking. So have ordered new parts from the states and waiting for them to arrive in NZ. Then should all be sorted. Thanks for your replies though. Much appreciated

 

[doug7740]

I hope that you ordered a neoprene seal and not a rope type seal.

doug7740
1955 Thunderbird Blue