1963 coupe axle rubbing arm

[N8]

I have a coupe I'm working on bringing back from the dead and is close to being on the road. During the test drive today there was grinding noise, so I jacked it up and saw both axles were rubbing the bottom of the a arm slot. The car is a spyder, but I have a monza engine in it for now and will rebuild the spyder engine later.

What is the issue? Are spyder engines heavier? I don't think they would be by much. Could the engine be mounted too low? What do you think would cause this? It's the same on both axles.

Photo

https://photos.app.goo.gl/yKJ6UmDNCnEy2KG89

[dbcorvairracer]

Engine weight is roughly the same, slightly heavier due to the turbo, however not the issue here. Most likely failed motor or trans mounts. Check the motor mount at the back of the engine compartment, or the two mounts at the front of the transmission holding the transmission up to the crossmember.

[N8]

I'll snap a photo of the mounts later today. They are old and tired, but not failed and I was hoping to hold off on replacing those for a bit to spread the cost of this out. I remember there is thread left in all the mounts so I can raise the engine a bit. I'll try that and report back.

[joelsplace]

Threads left?
From the picture it looks like the powertrain is too far forward.
Check the toe. I'll bet it has severe tow out.
If it does fixing that will pull the axles away from the control arms. I don't recall ever having one rub in that location.

[N8]

Trans mounts are saggy and need replacement, so I'll order some and hope that solves the issue.

[N8]

Photos:

https://photos.app.goo.gl/Pf2Gg29yEeZaNamg6

I ordered trans mounts and the engine mount.

The engine is farther back than I would like. Hopefully fresh mounts shift things forward.

[N8]

Threads left?
From the picture it looks like the powertrain is too far forward.
Check the toe. I'll bet it has severe tow out.
If it does fixing that will pull the axles away from the control arms. I don't recall ever having one rub in that location.

You just opened up a whole new world to me. I'll look into that. I just read that trans crossmember shims affect toe. Since I'm too far rearward I would like to remove some of those if the new mounts don't correct the issue. The front side of the engine is noticeably low currently as well.

[joelsplace]

In the picture the transaxle seems to be too far forward. Transmission mount are very important to handling on your Corvair.

[jimbrandberg]

You mentioned the engine seeming too far forward. There should be shims between the front of the transmission and the transmission mount bracket. These are also what adjust the wheel toe in or out like someone else mentioned.
Toe out will make if feel scary over road undulations.
Jim Brandberg

[Rick4130]

Those mounts are fully thrashed! Replace them for major peace of mind! :)

[N8]

Update: I replaced the trans and engine mounts with new. I torqued them 70% less than spec because I used antisieze and read you should reduce the torque because the fasteners are lubricated. Drove around the block gingerly and all was good. Drove around aggressively and the axles rubbed again. Looks like everything shifted rearward because there was 1/4" space from the oil filter housing to the frame and now there is 1/8 or so. My plan was to jack it up tomorrow morning, loosen the mounts, shift forward, and torque to spec. I'm just posting to see if there is something else I should look into. Could a loose crossmember bolt cause this?

Thanks again,

Nate

[joelsplace]

The engine position sets the rear toe. It will have to be wherever it ends up to get proper toe in.
It is possible your rear subframe is loose or the mounts are bad.

[Dennis66]

I was going to say check the subframe mounts. I just replaced mine last weekend. The front ones mount at a forward angle, so if the bottom half is shot, that could allow rearward movement. On the other hand hard forward driving should be pushing the powertrain forward. Dennis

[N8]

Thanks for the replies. The driver side subframe mount that goes at an angle seems like it won't get tight and the bolt pops when tightening. It's like the captured nut is partially stripped. How would you guys fix that? Helicoil? Drill out and tap larger? The bolt doesn't fall out but it won't torque down properly. I don't see how that nut would ever be replaced. I have the interior sripped out so I guess I could cut an opening to access the nut from inside the car.

What do you guys think?

[jimbrandberg]

I've never had one of those rear nuts stripped but had a few bolts break off that had to be drilled out, quite a chore with a Grade * bolt.
I don't know what I'd do in your situation. I'd have to wonder about tapping it for a slightly larger metric bolt. With sockets, 13mm is a tad larger than 1/2". Now that I'm thinking about it I don't remember if those bolts are 1/2" or 7/16.
I suppose a thread repair like Heli-Coil or something would be something to think about.
Any chance the nut is good enough and the bolt is stripped?
With the way any of those suspension crossmembers are mounted to the chassis I've always felt the contours help them stay in place as much as the bolts but with the rear hockey pucks maybe that isn't true.
Just sort of thinking out loud, I can't bring the specifics to mind sitting here.
I don't know if that's your axle rubbing problem but it is something that should be corrected. There's only a few of those bolts.
Jim Brandberg
Isanti, MN
CorvairRepair.com

[Dennis66]

They are 7/16. Just had mine out last week. Next metric size would be 12MM. Helicoil would be very difficult to do without dropping the while subframe. Dennis