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Discussion Starter · #1 ·
This is mostly a "check me on this" sort of question.
I've got a propshaft vibration that smooths out (mostly) around 2500 rpm.
The PO had just done the Guibos and support bearing, and he thought it was the bearing. He just drove it anyway (boggle).
He also drove a full set of shredded CV boots, which had me under the car this afternoon replacing halfshafts.

Two things.
The rearmost guibo looks like the driveshaft is about 3mm shorter than it should be. The flange 'ears' are deforming the guibo towards them, so that the molding line on the guibo is visibly wavy. OTOH, I've never held a new one, so I don't know if they should be flat or not. I didn't loosen the bolts, but I'd bet that the guibo would 'relax' to flat if I did.
My first thought that I could include appropriate washers in the bolt stack to add the necessary thickness. Nice big washers. Is that an acceptable kluuge? I'm going to replace the guibo anyway, since there are visible cracks in less than a year.
Any easy sources for those big hose clamps to compress it?

Second, the rear engine mount (bellhousing mount) is visibly off-center. PO told me that he failed to drive it all the way through, and apparently couldn't think of a rig for the job. I'm guessing that's a factor in the vibration I'm getting. The mount is probably 2mm off-center. If it doesn't matter, I'm happy. There's enough else to fiddle with.

And last (sorry). The Haynes manual says there are two pad adjusters per caliper. I can only see one. I have an extra transaxle on the floor with calipers, and I can still see only one. Am I missing this or is Haynes wrong?

Thanks,
Eamon
 

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. . . . The rearmost guibo looks like the driveshaft is about 3mm shorter than it should be. The flange 'ears' are deforming the guibo towards them, so that the molding line on the guibo is visibly wavy. OTOH, I've never held a new one, so I don't know if they should be flat or not. I didn't loosen the bolts, but I'd bet that the guibo would 'relax' to flat if I did.
Yep, flat. Not really sure why this happens. Comes up all the time, most recently here. My Alfetta is the same at the moment, having recently pulled the TA for bushing, etc. Was it wavy before the TA was pulled? Not sure now as the giubos were recently replaced right before. The TA has some fore/aft adjustment, but mine is full forward and the driveshaft is still short.
. . . . My first thought that I could include appropriate washers in the bolt stack to add the necessary thickness. Nice big washers. Is that an acceptable kluuge? . . .
In the link, Biba said he added washers as you have suggested. I might try that but will looked at a few other things first including replacing the rear engine mount first.
. . . I'm going to replace the guibo anyway, since there are visible cracks in less than a year. . . .
The lifetime of a giubo that is 'wavy' must be greatly reduced.
. . . Any easy sources for those big hose clamps to compress it? . . .
Most anywhere but the big box home improvement stores, in the plumbing section, should have a good cheap selection.
. . . Second, the rear engine mount (bellhousing mount) is visibly off-center. PO told me that he failed to drive it all the way through, and apparently couldn't think of a rig for the job. I'm guessing that's a factor in the vibration I'm getting. The mount is probably 2mm off-center. If it doesn't matter, I'm happy. There's enough else to fiddle with. . . .
Alignment is pretty critical. However for 2mm I might wait for when you pull the driveshaft for giubo replacement. I would definitely put this on the must do list though.
. . . And last (sorry). The Haynes manual says there are two pad adjusters per caliper. I can only see one. I have an extra transaxle on the floor with calipers, and I can still see only one. Am I missing this or is Haynes wrong? . . .
Haynes is right. Adjusters on either side of the caliper. Here is a link to a PMB Performance rebuild. The outboard adjusters face aft where the inboard adjusters face outward.
Good luck and please keep us informed.
Gerry
 

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Here are pictures of the adjusters.

You can make a big hose clamp by connecting two or three smaller ones together.
 

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This is mostly a "check me on this" sort of question.



The rearmost guibo looks like the driveshaft is about 3mm shorter than it should be. The flange 'ears' are deforming the guibo towards them, so that the molding line on the guibo is visibly wavy.




Thanks,
Eamon
The problem here is incorrect pinch bolt tightening. I have data on this issue on my driveshaft page at Silicone Hose Kits

Greg
 

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Discussion Starter · #5 ·
Sorry,
I should have specified: It's a sedan. Two shaft halves, three guibos, no pinch bolt.
That would have been much too easy.

Thank you,
Eamon
 

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Giubo, not guibo. Romeo, not Romero.
 

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. . . I should have specified: It's a sedan.
More importantly, you should have specified the model. I was somewhat surprised to reread your first post to find it wasn't mentioned. Based on your previous posts, I had assumed we were speaking of an Alfetta.

Continuing on that assumption . . .
. . . Two shaft halves, three guibos, . . . .
Common to the 116/119 Alfetta/GTV6/Milano.
. . no pinch bolt. . . .
Right. No spline/pinch bolt on the Alfetta.
Herein lies the crux of the problem. The only adjustment for propeller shaft length is the transaxle position and this is maybe only 1/4-1/2". This has been an issue with too many here (or so it seems) for it to be random/accidental/etc. I'm voting for the giubo thickness conspiracy (remanufactured design is thinner?) but do not have basis.
Since the Alfetta doesn't have a pinch bolt/spline and with the transaxle fully forward and the carrier as far aft as possible, what else could it be? On one hand the idea of adding washers to the assembly to make up the length difference doesn't leave me with a warm and fuzzy (a bit shade tree) but on the other, having the rear giubo misaligned is a no-no.

You say you have the Haynes manual. If it is the '73-'80 'Sedan & Coupe - All models', then Figure 8.3 on page 134 shows adjuster placement/information.
 

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I used to have early Alfetta donuts on my car. Now I have late Alfetta donuts on the front and rear. The late ones are about 3 to 4 mm thinner than the early ones. Don't know when the TA input yoke was lengthened.
 

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I'm having this problem on my 75 twinspark (same shaft, no pinchbolt), so, are you guys suggesting repositioning the TA forward, I have the removable crossmember, so I guess would just be a case of slackening the crossmember, pulling the TA forward then tighten? I guess there is some element of trial / error getting it to settle right, with the factor of all 3 TA mounts and rear giubo pulling against each other?
 
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