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71 Berlina 74 GTV 17 Giulia Q4
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Discussion Starter #1
Embarking on replacing the front crossmember. The shop that fixed my car from when my buddy let it roll down a hill got it in off center. one wheel is into the wheelwell to far and the other is out of the wheelwell to far. I've been putting it off for a couple of years but the motor is performing so well it just ain't right to have it in a below par chassis. It's not going to be easy and to be honest I'm a little intimidated. I just need to approach it like my first gearbox rebuild by breaking into manageable steps.
 

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Watching with interest.

Ken
 

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71 Berlina 74 GTV 17 Giulia Q4
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Discussion Starter #3
The factory manual says to chip out the welds and whatnot with an air chisel. I can attest to the fact it's easier said than done. The book says 690mm between the skirts at the steering box/idler. I've got 679.

1624591
 

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71 Berlina 74 GTV 17 Giulia Q4
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Discussion Starter #4 (Edited)
I gave this diagram minus today's numbers to the shop that worked on my car over 3 years ago. Even supplied them with a new crossmember which they put in exactly where the old one was. I got my other crossmember placed and the dimensions are exactly what the factory calls for. I did have to move the left side ahead some but that only took less than half a day. Why they couldn't do that back then is beyond me. Everything is lining up great and all I can say is FINALLY! (edit) The diagram is the last image, it was supposed to be first.
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Quality work here

Pete
 

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My Tiger has a removable crossmember that also holds the front suspension. Like many, my car had been wrecked in front, measurements between attachment points were off. It was amazing, when we tried to spread the frame rails with a power ram, how much it bounced back when we took the ram out. We had to press quite a bit wider than the final number we wanted to get it to relax to the right number. Was very tense, metal groaning and creaking. Finally got our number and put a bunch of new weld in to hold it.
Amazing job here, congrats on the work.
Andrew
 

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71 Berlina 74 GTV 17 Giulia Q4
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Discussion Starter #7
I know what you mean about the creaking and groaning, serious pucker time. I also had to go past the spec of 690 side to side to get it to relax there and let it sit under stress overnight. I don't know if it helped but I felt better. I'm excited to get the tie rod ends and center track rod to be within factory limits and having the front wheels ahead of the rear wheels instead of off to one side. and Thanks, much appreciated!
 

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Mike, if we encounter a zombie apocalypse and have to build a space shuttle to escape the collapse of civilization, I definitely want to be on your team!
 

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Have you checked diagonal measurements as well as longitudinal? Just want to check that she is not a parallelogram, before you go much further.

Pete
 

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71 Berlina 74 GTV 17 Giulia Q4
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Discussion Starter #10
A good friend of mine retired from NASA and worked on propulsion among other things and I've asked him about building a liquid fuel rocket motor. The pumps are the tricky part.
I got my laser measuring device today and I'll check the diagonals. I have I think addressed that possibility though. I'll run it by and I'm open to feedback. On the spare block that is mounted to the crossmember I have put a piece of pvc pipe in #s 3, 4, and 5 main journals which in theory should line up the block/crossmember through the crankshaft straight back. With a half inch pipe going back from the center of the main journals almost to the flange on the dif. Tweaking the position of the crossmember to get the pipe perpendicular to the rear wheels at the dif flange and in line with the crankshaft makes a square. My main concern being having the driveshaft/crankshaft/diff flange all in a straight line. The previous crossmember was off (if I write c o c k e d the admin guys put asterisks to block that particular word which describes the position of the crossmember) which put the output flange of the gearbox angled off to one side. The laser measuring makes it easy to check and I'll check my work by measuring the diagonals. Thanks, two heads are definitely better than one!
 

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I had not realised that the driveshaft was dead straight.

Pete
 

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71 Berlina 74 GTV 17 Giulia Q4
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Discussion Starter #12
First thing I did car wise this morning was check the diagonals. But before we get into that I've got to say this laser thingy is way, way, cool. Besides the screen being backlit which makes it super easy to read it also has a history which keeps the last 5 measurements displayed and with all sorts of geometric functions it's as my Daughter would say "da bomb". And it's dust proof and water resistant! I had to measure the diagonals, from the front outside A arm mounting hole to the center of the outside mounting hole of the small cross brace, several times because I couldn't believe they were so close. 1212mm and 1213mm! The factory measurement distance is 1153 +- 3mm and I'm still at 1153 and 1152. That makes the driveline from the center of the crankshaft back to the center of the dif flange perpendicular to a line drawn through the center of the rear axles. Pete, thanks for the mentioning the diagonal measurement. Confidence is high :)
 

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71 Berlina 74 GTV 17 Giulia Q4
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Discussion Starter #14
Front wheels are even with the rear wheels, finally. Praying tonight for one more scratch free single person motor stab tomorrow.
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I had the cross member replaced in my 64 Sprint GT after the really inadequate front lower inboard bushings (don't understand why they didn't have grease fittings since it was difficult to lube the original) froze up and tore out. The shop said it was an easy job, and didn't charge me much after I supplied them with a new part right from the factory.
 

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71 Berlina 74 GTV 17 Giulia Q4
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Discussion Starter #16
I'm not quite sure why the crossmember needs to be replaced when the lower A arms are bolted to the crossmember by 4 bolts a side and the bushings are inside the A arm? Maybe the earlier ones are different.
 

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The early lower inboard bushings (mine was just the 6th production Sprint GT model sold so I was told by Carlo) froze up solid because they couldn't be lubed worth a darn, and tore the flanges right off of one side of the crossmember, dropping the inboard end of that suspension. Exciting to learn just how bad those bushings were, even with attempts to lube them (no grease fittings, just a little foam of some sort (IIRC) which was supposed to retain lube, but instead just held water. Really terrible design by Alfa.
 

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And early 105's had 2 bolt lower inboard dog bones, instead of 4 bolts, so if the bushing was tight (seizing) it would put narrow twisting forces on the cross member resulting in metal fatigue.

Pete
 

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Yep, there's a factory bulletin on this, and I've read anecdotally that 105 cars had crossmembers tear out as early as 64/65, but it still took some years to sort it. A friend's 67 Super here had the crossmember repaired last year, and I had a 65 US TI with shipyard-size electric welds all over it from some dim time in the past.

Good luck with the engine/trans.

Andrew
 

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Yes it was a poor design and could not be lubricated. It was meant to be replaced before it seized up. Exactly how you monitored that and what guidane Alfa gave eluded many first time owners of well used cars until damage was done or they noticed some other wat.

K
 
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