Partial engine drop -- how much needs to be done?
 

It looks like I'm going to have to do a partial drop to swap in the new trailing arms on my '72. I'm going to -try- to replace the thermostat seal, etc on the top of the motor while I'm in there.

But the real question is...what can I get away without removing? I'll likely have pulled both CVs by then anyways. I figure that the shift coupling, throttle cable, clutch cable, and some of the electicals. But is it reasonable to leave things like fuel and the main wiring harness hooked up? Will I be able to get away with loosening the rear engine mount bolts, and just lowering the tranny?

For those that don't know, 72 and 73 are lucky enough to have an interference problem between the trailing arm bolts, the torsion tube, and the transmission. Unless the torsion tube was -notched- and the bolts were re-installed the opposite way, one cannot remove the trailing arms without a partial engine drop.

My guess is that if you don't drop the whole thing it's really two different projects and/or motions.

On my car you can get to the thermostat seal by just dropping the back.
2 bolts out of the rear mounts and maybe the main harness and it will come down about 3-4 inches. It isn't easy, but you can get to the t-stat from the top that way. (Luckily you don't have all the CIS stuff in the way)
On my car you can also get to the same area from underneith because that part of the engine tin is removable in sections. (I don't think your's does this.) So this part is probably relativly simple.

At this point half is loose. If you remove the transmission mount, you might be able to slide the engine and trans back 2-3" with the coupler still attached. That's probably also where your going to hit the rear crossmember behind the fan. Hopefully at that point you can get to your bolts. If not it looks like maybe you could then discomnnect the coupler.
Maybe it's better at that point to raise the transmission up as far as it will go in the tunnell.

These are just some thoughts.
Since the t-stat is doable, maybe just post the one question on PP.
With the volume of traffic there someone will probably answer you with at least a go or no go!
Good luck!

I don't think you will gain much by a partial engine drop. This is usually when one disconnects the engine mounts and lowers the engine with a pivot on the tranny mounts. The tranny does not drop very far until the select shaft hits the tub.

You will also not be able to move the drivetrain back far enough to clear the trailing arm bolts.

I think you will have to drop the whole drivetrain to get at those bolts. I did on my 71. If you already have the CV's disconnected Its only two sets of wires, one fuel line, a shift coupler and 4 bolts from being out of the car.

He knows, listen to him :!:

Well, I don't have any problem lowering the entire engine and transaxle. On a '72, there's not a whole lot to disconnect. Hopefully I'll be able to loosen up the trailing arm bolts with an engine partially obscructing my access (lowered, but still under the engine bay). I hear it takes some significant force to loosen up the trailing arm bolts.

Josh, You should be able to jack the car up high, lower the drivetran on the ground and have plenty of access to the bolts. Of course, if you use a rolling jack or ATV setup just pull it out from under the car and give yourself plenty of room.

A std. breaker bar should be enough. Of course, always keep that 3ft section of pipe handy just in case. Also make sure it fits on the end of your wrech/etc. A section of uni-strut will also work in a pinch. I had to use a large cresent wrench on the back side. There was not enough clearance for a socket that size and I didn't want to cut one down.

The trailing arms will be tight in the mounts. You will have to wiggle/wrestle them out and the new ones in. A soft dead blow hammer works well here. Use a round drift through the bolt hole to help in alignment.

After the swap just lift the engine back up into the car. You are right, on a 72 there isn't much to disconnect. Later cars too, it just looks complicated with all that CIS crap in the way. Take that SCWDP! :twisted:

btw, are you installing new stock bushings or monoballs in the Al arms?

Anything that’s been in place for 32 odd years will be a little “reluctant”. But the real issue is getting them free of the bush, while not mushrooming the bolt ends or bending the rear shift rod trying to get the transmission low enough to swing that BFH.

Vice grips, Liquid Wrench perhaps some heat and many @#$ words! I too think it is better to just pull the drive train out and be able get in there to work. You now have a reason to look the top end over and fix/clean things up.

Thanks for all the tips.

I'm trying to avoid having to jack the back of the car up to the stratosphere to clear the stacks. I already have the car on 4 jack stands. I can disconnect the shift rod to help lower the tranny even further. My shifter will need a re-alignment anyways after I install a rennshifter as well as Charlie's bushings.

I have another set of trailing arm bolts, so if I were to damage them, it wouldn't be the end of the world.

I'm also swapping in a set of monoballs. Rennline is having a Christmas sale right now -- 15% off.