transmission support bushing- need advice

[Andrew]

Even the German repro rubber mechanical clutch type mounts (for early GTV, TI, Super, Duetto) are much stiffer than the original Alfa ones. I had one in my 67 Super briefly and could not stand the vibration. I went back to a hydraulic type mount, with a rubber bumper to stop trans fore/aft movement, and am much happier. I can back up just fine now without axle judder.

Andrew

[msiert]

To see how much the tranny moves here's a video clip of my tranny under load with a new bushing.

http://www.alfabb.com/bb/forums/468992-post1.html

[mhunger]

Quote:

Originally Posted by George Willet The height of the rear mount and the crossmember is different between the mechanical clutch and hydralic clutch. Substituting the rear mounts can cause a missalignment of the "donut" and of the u-joints, resulting in a vibration that is hard to solve, let alone increasing wear on the components. Stick to the correct parts unless you are familiar with gauging driveline angles.

[Andrew]

The trans is meant to move around some. The aftermarket mechanical clutch (1600) mounts will, in my view, allow too much vibration through. The hydraulic clutch mounts dampen the vibration better, but make it hard to back up in a mechanical clutch car without some kind of rubber bump-stop arrangement to keep the trans from moving fore/aft in reverse.

Andrew

[mhunger]

I am still having a bit of a problem. to recap, I have a 2l driveline in a 66 sprint gt. I have the 2l tranny support bushing. I don't know which support bracket I have. It could well be the original one. The driveline makes a noise / vibration when coming off the throttle at highway speeds. I have 2 questions:
1) is there any way to tell if I have the earlier or later tranny support bracket
2) how can I check for the proper driveline angle.

any help would be much appreciated

marc

[Andrew]

Is there a different between early and late 105/115 trans support brackets? If so, I didn't realize. I know early ones for floor-pedals cars need the cutout at the front to clear the brake MC, but I kinda thought the late ones had that too, just because there was no reason to retool to fill in that cutout.

The on/off vibration problem could be u-joints, sliding spline looseness, ring and pinion wear, internal trans wear. I haven't read back through every message, but have you eliminated all that? In my experience trans bushing vibration and noise is the same whether power on or off.

Andrew

[BigSwede]

Quote:

Originally Posted by msiert To see how much the tranny moves here's a video clip of my tranny under load with a new bushing. http://www.alfabb.com/bb/forums/468992-post1.html

[msiert]

Quote:

Originally Posted by BigSwede Now that was a brilliant post!

[Alfajay]

Mhunger had asked: "I have a 2l driveline in a 66 sprint gt. I have the 2l tranny support bushing. I don't know which support bracket I have. It could well be the original one. The driveline makes a noise / vibration when coming off the throttle at highway speeds. I have 2 questions:
1) is there any way to tell if I have the earlier or later tranny support bracket
2) how can I check for the proper driveline angle."

1) Yea, the 2L support bracket positions the through bolt a little lower than the 1600 bracket. I suppose this is because the flexible bushing is more offset on a 2L than on a 1600. Oddly, the dimensional difference between the brackets seems to be less than the difference in offset between the bushings. Which one to use in your '66? I'd go with a 2L bracket if you are using an offset bushing, though if you don't have a 2L support, you could always shim your 1600 support lower using longer bolts + flatwashers.

2) (I learned this on the BB - I can't claim credit for thinking it up.) Replace your Guibo joint with three stacks of washers, whose height approximates the thickness of a Guibo. Bolt your front driveshaft to the transmission using these washers - now you have your driveshaft on the same axis as your transmission mainshaft & crankshaft. Use a support bracket and/or shim your support bracket so that the front driveshaft lines up with its bearing support - that is, so that the driveshaft bearing support isn't under any load.

Of course, I'm not suggesting that you would drive your car with washers instead of a Guibo - this is just a way to check the alignment. The Guibo is intended to accommodate radial torque, but not misalignment between the transmission and driveshaft.

[70ep]

After today,I suggest anyone installing this mount to check the OD against the one that came out. I've had the new mount for a year or so and don't know where it came from but with a vernier set for go/no go I found (after trying to install and thought there was too much resistence) that I had to grind a substantial amount of OD off to match the old mount.

[argtv6]

Is there also a difference in the inner sleeve length between the early centered and the later offset bushes?
I have come across a narrower bush dimension crossmember with added crossmember to chassis holes on a botched up 66/67 mechanical clutch stepfront.
I wouldn't be surprised if it came off a saloon or spider.