How to change motor mounts on finished car

[MikeD]

Ok, the background:
my car has a balanced 351W with convertible motor mounts in it. It has been on the road since 2003, and has about 20,000 miles on it now, and the pipes have always moved too much. In fact, they move so much that they broke the hangers off the pipes. So I have been running without hangers for most of the 18 years on the road.
I added a torque strap from the frame to the drivers side head for a while, and that helped a lot, but I took that off a few years ago. (can’t remember why, at the moment…)

Now I’m thinking I will replace the motor mounts with some solids I just bought, as a winter project.

My question: Can I support the engine from the bottom somehow while changing the mounts? I don’t think I can put a jack under the Gordon Levy road race oil pan without crushing it. Other options?

Or do I NEED to use an engine puller and lift it from the top using the intake manifold?

Thanks for any tips!!
MikeD

[Rdone585]

I would not put pressure on the oil pan, use an engine hoist. It's not too difficult. You will most likely also need to loosen or remove the tranny mount so the engine will rise without damaging it. You can put some bolts with a heavy chain in the heads from corner to corner across the engine. You can use layers of cardboard between the chain and the valve covers to minimize scratching them. Other choice is to remove the carb and use a lift plate. You only need to lift the engine an little over an inch. Make sure the side pipes have the clearance needed to lift the engine, otherwise they will have to be removed. Just take it slow and watch all the points where what you are lifting can hit what's not lifting.

[edwardb]

I've done this before a couple times. But be prepared. It can be a handful. Absolutely agree 100% lift it from the top with an engine hoist. Loosen the transmission mount. But my experience is it doesn't have to be disconnected completely. Unless you have the shifter and driveshaft tunnel in place. Then it could hang up there when raised. Just be prepared for the engine to move around a bit once the engine mounts clear the chassis mount. Don't have your arms, hands whatever in there one it starts to move. Once you have it up high enough, swap the engine mounts and drop back into the chassis just like you did when first installed. Good luck.

[cob427sc]

I have replaced one (drivers side) when the donor engine mount tore back in 98 and I was not near home. Used a floor jack and a piece of wood blocking on the engine against the head and lifted the engine on that side just enough to pull out the old mount and slide in a new FOMOCO mount. You could probably do the same , one side at a time but lifting the engine would be best.

[OVCobra]

You indicated that you were going to "replace the motor mounts with some solids"...if you mean solid motor mount two things to be aware of;
1) there will be a significant increase in noise and vibration (due to the loss of dampening from the elastomer(s)),
2) you will need to change the transmission mount to a solid mount

Just make sure that motor and transmission mounts have similar elastomers ( rubber, polyurethane, etc.) ideally complete set from one manufacturer.

This is pretty much pure race car stuff and not really intended for street cars IMO.

[Rdone585]

I put solid engine and tranny mounts in when I first built the car. Later I was told with solid mounts on both it put extra stress on the drive train. I soon found out that the tranny should not have solid mounts, so I changed to a urethane tranny mount. I've been running like that for the last 17 years on street and track.

[MikeD]

Thanks for the replies guys!!
I bought solid motor mounts from American Muscle that include the transmission mount. I am aware it will make the car even more hard-core then these cars are. (As you guys all know.) I like the idea of changing it up after 19 years on the road.

I really haven’t done anything big to the car except drive it in that time. So I’m embracing the modifications. If I end up not liking the solids, I will go with poly mounts in the future.

Thanks again for the tips!!

MikeD


https://youtu.be/q7PLk2fpcas

[CraigS]

If you don't have an engine hoist get a come-a-long and a big long eye bolt from your ceiling. I ran the eyebolt through the drywall and up through a 4x4 that spanned 2 trusses. BTW the trusses were standard non storage type and it worked fine for removing and installing my 351.

[John Ibele]

Hey Mike - have fun mixing it up and keeping it new. I'm sure it's on your list but just in case, don't forget to recheck drive shaft angles and make sure you're happy w ground clearance w.r.t. frame. I'd expect the motor will come down a bit.