This ain't good I'm guessing. Don't remember those cracks when I installed these mounts. What would cause this?

 

Are they new? What brand are they?

 

I would not drive that car except to move it around your driveway. On motor mount failure: old or bad rubber on the mount, or an engine more unbalanced than Rachel Maddow.

Your pictures are very good, by the way. In focus, well lit, and good angle.

 

Also, I caution you not to apply too much power. I had a broken motor mount and the motor lifted high enough for my carburetor stud to put an outward dent in my hood. It was an eyesore.

 

I agree with all that has been said. I don't know the reason if all seemed to fit properly. Try a different source next time. Until you get them changed avoid all maneuvers requiring significant torque. Take pride in your photography, and remember that "crack kills".

 

Yeah. Those are no good.

Probably old rubber.

Get new ones.

- Eric

 

It's hard to tell from these photos, but it APPEARS that you have frame mounts from a 350 car and motor mounts from a 455 car forced into place. Those frame mounts need 2261 motor mounts, NOT 2328 motor mounts. The fact that the motor is a 455 is irrelevant.

 

Check out the crack in the third arch of this bridge. Looks dangerous.

 

Nice photo, you can even see the pimple on his A$$.

 

Thx everyone. Car is still in build stage so this happened just in the shop. They are used mounts but were not cracked when I put them in. I think Joe is right, I had a heck of a time getting then to line up. Might be wrong combo.

Are the 2261's shorter? Maybe thats why my headers were touching my airbox.

 

Once again, Olds motor and frame mounts MUST be used as a matched set. When matched correctly, the crank centerline will be in exactly the same place with either combo. Mismatch and the motor will sit too high (assuming you can force the incorrect mounts into place at all).

I assume this car was originally a 350 car that had a 455 swapped into it, and you bought "455" motor mounts, correct? Using the incorrect 2328 motor mounts with those frame mounts will 1) raise the motor about 1" and 2) stress the rubber mounts, causing the installation problems and cracks you see.

 

How did you get your start in becoming the "Oracle of Oldsmobile's"? Did this trek begin in your teens, I assume?

 

While Joe is in the pulpit on this Sunday on the subject of motor mounts, if the matched sets (350 pads and mounts, vs 455 pads and mounts) put the cranks in the same spot, what is the difference between the sets overall? Are the 455 ones heavier duty?

 

Ohhh, I LIKE that! I may have to get shirts made up.

Yup, which for me was 1974, when I got my license and inherited the family 1968 Vista Cruiser as a first car. I promptly replaced the 350 with a 425, which is where I learned about the different crank flange bolt patterns.

I couldn't afford to pay someone to fix my stuff, so I learned. The next car was a 68 442 pulled from a wrecking yard and totally rebuilt over three years. The rest, as they say, is history.

 

https://classicoldsmobile.com/forums...tion-list.html

Read posts #23 and #25, specifically.

 

Ok, I see. No real advantage for any particular set, other than you want the "come apart" fail safe.

 

The 2328s are marginally stronger, and are used across the board starting in the mid-70s, but now that the 2261s also have the fail safe, other than optical reasons there is no real advantage one way or the other. Just match the frame mounts.

 

Spring is here

 

His? I apologize for starting the deviation of subject material when serious matters are at hand.