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Burman Box Cracks...

5K views 37 replies 16 participants last post by  gigem75 
#1 ·
I'm in the process of rebuilding my '74 GTV, and I've read probably way too much about Burman Box cracks... So while I have the engine out being rebuilt, I figured I'd pull mine and check it out. Overall it looks pretty good, but there are a couple of micro-cracks along the lower right bolt hole. I don't have a dye kit, but I cleaned it up, and went over it with a magnifying glass and a bright flashlight. I had kind of resigned myself that I was going to need to bite the bullet and get one of the Billet Alfaholics ones, but I started to get really optimistic when seeing the condition of the current box. I may still go down the Billet path for peace of mind, but it really doesn't look bad to me (though this is my first experience with rebuilding an Alfa, so what do I know?). Thoughts?

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#2 · (Edited)
I'm not an authority on cracks in Burman boxes. But most reported cracks are toward the top and front of the box, where the two steel plates bolt on. I don't think the bottom - where your red arrow points - is a common stress point.
 
#5 ·
I'm not an authority on cracks in Burman boxes. But most reported cracks are toward the top and front of the box, where the two steel plates bolt on. I'm don't think the bottom - where your red arrow points - is a common stress point.
I’ve had a box crack in this location so it can and does happen. I thought my alignment was off, and when I had checked, I was given the bad prognosis. The box prior to this cracked in the more common top cover bolt location. I’m on my third and hopefully last box.
 
#7 ·
I'm in the process of rebuilding my '74 GTV, and I've read probably way too much about Burman Box cracks... So while I have the engine out being rebuilt, I figured I'd pull mine and check it out. Overall it looks pretty good, but there are a couple of micro-cracks along the lower right bolt hole. I don't have a dye kit, but I cleaned it up, and went over it with a magnifying glass and a bright flashlight. I had kind of resigned myself that I was going to need to bite the bullet and get one of the Billet Alfaholics ones, but I started to get really optimistic when seeing the condition of the current box. I may still go down the Billet path for peace of mind, but it really doesn't look bad to me (though this is my first experience with rebuilding an Alfa, so what do I know?). Thoughts?

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I went through the same soul searching a few years ago on my GTV. I ultimately went the Alfaholics billet box route as I felt the risk was too high. Rebuilding the box was not difficult given the documentation provided on the BB. I was also lucky the internals of my box were in excellent condition. FWIW, the product from Alfaholics exceeded my expectations; the new box is beautiful and the car handles very nicely. I also put reinforcement plates on the body to stiffen the connection points for the box and idler. From what I have read on the BB, the relatively thin metal at the pickup points can fatigue and twist the boxes which is a big part of the mechanism of failure.

By the way, the cracks I found were also very fine. I did not really notice them until I completely cleaned the box and found them on the inside of the box. As I traced them, I also found they had traveled completely from the inside to the outside of the upper boss on both the front and back of the box.

I hope this helps.
 
#8 ·
Unless your going racing. I wouldn't spend the money on the billet box. Alfahoilcs has a standard reproduction casted box for half the price. With modern aluminum it should hold up fine.

Contact them and ask about them.

 
#10 ·
Scrap it. I started repairing mine and the more I welded the more cracks appeared. Cracks radiate from the plate screw holes to the bore. They fail because of bad design ie the threaded hole is too close to the bore. Good money after bad. I went for the AH billet one as im fitting pas as well and the strength should compensate for the bad design.
 
#11 ·
It not a bad design. They have lasted over 40 plus years.

If its was truly a bad design. They would have started failing when were 10 years old in the 70's.
 
#13 ·
Well. I don't build aircraft and an Alfa is not an aircraft. I'm sure if you took one completely apart. You would probably find at least a third doesn't meet aircraft standards.

Kinda like buying an orange then being mad that it doesn't taste like an apple.
 
#14 ·
Well I did design and build aircraft and its basic Engineering standards irrespective of aircraft not rocket science, yes Im an Engineer. Those Burmans have been failing for many years for this reason. Its a fatigue failure not age related failure anyway. I have taken one completely apart. Took it apart and found it was a Lemon
 
#15 ·
Here, go to this thread discussion, it it showed the dye crack tested photos of the steering box.

 
#16 ·
No question that fatigue failure is a primary issue. But these production Alfa’s and their components probably had a design life of 5 years and 60k miles. The body. would rust out as the parts around wore out. If the car did survive, newer technology (like wider, griper tires) exasperated the marginal design of the original parts. By today’s standards, poor design, but for the day, it served its purpose.
 
#17 ·
Agree 100% with you. That is why I went the the billet box from Alfaholics. Well worth the money and security especially if you upped the HP, and use sticky tires with a less compliant suspension, all stressing the steering box.
 
#18 ·
This all definitely helps... Thanks. Even if it's just giving me permission to do what I wanted, which was spend more money than necessary on an upgrade. See honey, I had to get the $1,000 part because the lovely experts on the internet told me to. While I'm half-joking it is a safety thing, and I am upping the HP and putting wider stickier tires on her.... I'd hate to have the box fail, which largely sounds inevitable even if it currently seems to check out. I will talk to the folks at Alfaholics about their cast version, but you know might as well spend twice as much while I'm at it :) Thanks for the tip on reinforcing the body, Frank. I'll definitely do that, stripping to bare metal here in a month or two. Also, thanks for the link to the dye test, Classicalfas, I'll still check this one out when I get it completely apart, but it seems like no matter what the box should be replaced.
 
#20 ·
after 50 years of careless use (because that's how we drove them in the 80s and 90s) the alfa did their job.

we put on too big tires, we thought we were rally drivers and the parts of our cars got tired.

I used and used and threw a lot of alfa (I regret now), but it's only recently that on some "boxes" cracks appear. if you do professional welds and fit the tires to the original dimensions, you will remember to check your "box" in 30 years ...

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#26 · (Edited)
after 50 years of careless use (because that's how we drove them in the 80s and 90s) the alfa did their job.

we put on too big tires, we thought we were rally drivers and the parts of our cars got tired.

I used and used and threw a lot of alfa (I regret now), but it's only recently that on some "boxes" cracks appear. if you do professional welds and fit the tires to the original dimensions, you will remember to check your "box" in 30 years ...
thank you Chris...my tongue is bleeding driving style on oversized tires .. not just oversized tires.. just my opinion. seen it more often than not. We'll never prove any position so blood letting serves no purpose. I trust my instincts on a stock set-up and perhaps the fatigue factor will stay dormant until I die.
 
#21 ·
The experience with my personal 1974 2000 GTV does not support the idea of excessive stress from oversize tires as a mandatory cause. I've know the car since 1979; the original owner kept the car in fanatical "as new" condition until he traded it on a 1983 GTV6, at which point it had 20,000 miles and was like new. The next owner became a personal friend; he never raced or hit the car, just used it on a regular basis. The car stayed on 165 tires up until the point where they were about to blow up; I bought it from him in 2008 with 90,000 miles and brand new cheap and rather slim Hercules 185/70 tires. The car needed some work before I started using it; at which point I pulled the Burman box for cleaning and adjustment. The casing was cracked in the usual areas.

My daughter did some reverse engineering of the Burman box as a Mechanical Engineering end of class project. I obtained a failed box which was submitted to spectrographic analysis. A 3D scan of an unfailed box was performed. The resulting model was submitted to finite element analysis. The safety factor in the areas that fail is just marginal.
 
#23 ·
My daughter did some reverse engineering of the Burman box as a Mechanical Engineering end of class project. I obtained a failed box which was submitted to spectrographic analysis. A 3D scan of an unfailed box was performed. The resulting model was submitted to finite element analysis. The safety factor in the areas that fail is just marginal.
Cool stuff. Is her thesis (or the study) available somewhere?
 
#28 ·
Many of you know this, but Birman boxes don’t fail when the car is being driven, no matter the tire size. They fail when you are turning the wheel at very low speeds or completely stopped. The loads on the box are much greater then. To protect your box, commit to never cranking the wheel one way or the other without the tires rolling!
 
#35 ·
I went ahead and ordered a new billet box, just to be on the safe side. It could be overkill for my car, but better safe than sorry. I wasn't having any steering issues, but my engine is out so I thought I'd be proactive given the cracked box stories I'd read. I have every reason to believe that my internals are fine, but is there anything in particular to look for?
 
#37 ·
All good comments from experience.. I'll retract my theory on tire size alone albeit, it sounds like each example cited seemed they were on oversized performance tires( Mid-Ohio...".paddock" ). Just seems oddly a contributor..I am sure there are failures on spec tires too after 40 something years.
 
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