motor mounts

[EdwardGT350]

how can one determine if a motor mount is cracked or bad?
what are the signs?
will engine vibrate excessively?
how hard is it to change them?
which brand is a good quality?
are the hipo ones more robust?
im getting severe shuttering under load from a stand still and its particularly bad on an incline.
tia

[gt350hr]

   Early multi piece or later one piece mount?

[EdwardGT350]

for april 66 build.

[gt350hr]

   Your car "should" have later "standard production" '66 mounts. They are one piece and easily inspected for cracks in the almost 3/4" thick rubber that bonds the upper and lower halves together. There are several "improved designs" but they are obvious if you are trying to keep it looking "stock" . They are not too difficult to replace. Jack stands and a floor jack are a must have.
    The shudder you describe sounds more like a clutch/flywheel issue.

[67350#1242]

The driver's side usually the one to go first because is stretched by torque.
A good indicator with a 4spd is the shifter will tilt excessively to the right during acceleration.

[kjspeed]

Easy to check with a friend (or if you can see your motor from the driver's seat with the hood up). Put car in drive (auto trans) and slowly press the gas pedal as you keep your foot on the brake to keep the car from moving. If the driver's side motor mount is shot you'll see the engine lift up. Put the car in reverse and repeat to check the passenger side. With a good emergency brake you can do this with a stick also. If your E brake won't hold the car, then it's a bit trickier. Either way, make sure that there's nothing in front or behind you when you do this.

[S7MS427]

Put the car in reverse and repeat to check the passenger side.

I don't understand how this will check for a bad mount on the passenger side.  The engine only rotates in one direction regardless of whether the transmission is in forward, neutral, or reverse.  Am I missing something?

[SFM5S000]

Martin,
The best stock looking OEM type to me are the Lakewood "muscle mounts". They look like the stock ford pieces, but are interlocked.
Cheers
~Earl J

[427hunter]

how can one determine if a motor mount is cracked or bad?
what are the signs?
will engine vibrate excessively?
how hard is it to change them?
which brand is a good quality?
are the hipo ones more robust?
im getting severe shuttering under load from a stand still and its particularly bad on an incline.
tia

Are you sure it's not clutch chatter?

[EdwardGT350]

same shuttering occurred before the new clutch. i thought the new clutch would solve problem.
now we think its either the flywheel or oil from a rear main seal that got onto new clutch.
advised to slip the clutch or start in 2nd gear to hopefully burn off the dried oil.
shuttering ONLY happens when starting in first gear, especially on an incline.

[427hunter]

same shuttering occurred before the new clutch. i thought the new clutch would solve problem.
now we think its either the flywheel or oil from a rear main seal that got onto new clutch.
advised to slip the clutch or start in 2nd gear to hopefully burn off the dried oil.
shuttering ONLY happens when starting in first gear, especially on an incline.

You always have to resurface the flywheel when you change the clutch, oil will not burn off - it's the clutch and flywheel not the motor mounts.

[kjspeed]

Put the car in reverse and repeat to check the passenger side.

I don't understand how this will check for a bad mount on the passenger side.  The engine only rotates in one direction regardless of whether the transmission is in forward, neutral, or reverse.  Am I missing something?

Transmission output shaft in reverse applies torque in the opposite direction. With brakes locked it will lift the passenger side if the mount is broken.

Sounds like OP's problem is clutch related though.

[EdwardGT350]

where is the best place to jack up the motor to check or change the motor mounts?
can the jack be placed under the drivers side of the oil pan with a 2x4 piece of wood in between?

[Jbarela]

I am no expert but I experience the exact same thing in my mustang and in my bmw after clutch replacements.both times it was either the throw out bearing or the pilot bushing. I cant remember but I remember when the clutch was done one of those parts were not replaced and bam chatter..parts replaced and chatter was gone. I also went with needle bearing pilot bushing.