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Discussion Starter #1
I slid the car into a curb sideways. I've already ordered all the suspension parts that got bent, and I thought I was well on my way to being back on the road with some body damage still to be fixed, but rolling and driving none the less.

however, it seems my inspection of the damage missed one thing until today...

The sideways impact must have pushed on the axle enough to shift laterally a bit. The cast aluminum threaded holes that the motor mount screws mount to are both broken.

Obviously, replacing this part means some pretty significant work. The thought has crossed my mind that I could have that area ground smooth and have a piece of thick flat bar welded in there. If that were possible, I could re-position the motor mount to the right about 1/2" and bolt it thru the newly added flat bar.

The vibrations and forces associated with a motor mount make me uncertain if this idea is acceptable. Anyone have the kind of knowledge and experience required to give me some informed advice?
 

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I would take it to a Dealer and have a Lotus Tech look at it to assess the damage.
 

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I would take it to a Dealer and have a Lotus Tech look at it to assess the damage.
+1. If you've damaged the frame, speculation is a bad idea.
 

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Discussion Starter #6
That is good advice, and I would do so, but the fact is the nearest dealer is a 3 1/2 hour trailer pull. I know there isn't any structural frame damage. I have inspected every attachment point that the rear suspension connects to the frame. Everything did exactly as Lotus designed it. The Lower wishbone bent, the brake rotor broke, and a pair of tie rod ends bent. All that happened so that the frame attachment points could stay fine.

This problem is more mechanical than structural. Since the casting on the side of the transaxle broke, I'm trying to figure out if that casting in that place can be welded or if I'm going to have to pay a mechanic to yank the engine, replace that cast piece, which basically is the transmission from the looks of things, and put it all back together.

As for insurance, yeah, this is quickly looking like a claim, but given the circumstances around the incident, it gets complicated. If the fix I'm suggesting above would correct the issue without compromise, I'd rather continue to cash out this repair.
 

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Discussion Starter #9
Had to wait till I got to the office this morning to post pics. somehow I must have lost the data cable I had at home. Doh...

Here's the image of the damage to the area in question. Any suggestions other than towing it to Lotus? If not, that's what I'll do. Just fishing for options at this point.



Ok, so after previewing the post, I can see that the image is tiny and hard to see. Above the axle, the two shiny things are the bolts sticking thru the motor mount holes, but no longer threading into the cast attachment points since they blew out from the impact. I have both little cast pieces that broke out. They were clean break outs with no additional cracking on the case at all.

I'll see what I can do about increasing the image size a little.
 

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Discussion Starter #10 (Edited)
Maybe this image will be better. When I blow it up, it gets too grainy, so I tried to crop in just the damaged area.



Again, to clarify my idea for a fix. I would grind the cast area a tiny bit to creat a flat surface for a piece of angle to weld to the area where the bolts used to screw into. Then, I would re-position the motor mount as little as possible to allow its bolts to secure to holes in this new piece of angle that I would have just had welded to the cast transaxle case. The angle would then do what the threaded holes in the casting used to do, assuming the weld was strong, which I would pay an expert to ensure.
 

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It is hard to tell from the photo, but I believe you are trying to show that the transmission case broke and not the mount/frame of the car. If this is the case, and you say you still have the pieces of the case that broke out, they could be welded back into place by a skilled welder and then the repaired case would need to be taken to a machine shop to restore the original mounting face and threaded holes. Of course, it would probably be easier to get another Celica GTS transmission from a junkyard and swap it in or get a new/used transmission case and swap in your internals. At the very minimum, your transmission is going to have to be removed for any of the above fixes, so make sure that the case is the only broken part and nothing else has been damaged.
 

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It SOUNDS feasible. In theory. With a lot of caveats.

The transaxle case is cast aluminum, right? I would make durn sure that the person doing the welding has a hundred years experience in such things.

Instead of welding on angle to accept an altered location of the bolts, wouldn't it be better to build up the broken bungs and re-tap them?

xtn
 

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Dude that stinks but if the tranny is shifted by that much from the original mounting holes I would be very wary of a shift in the wole rear chassis. The rear crossmember is galvanized steel very strong compared to aluminum mounting portions of the a arms. It appears the impact shifted everything laterally. An alignment shop will tell you whether the rear section of the frame is bent with respect to the front. If you do what you suggested there is a possibility the engine will no longer be in alignment with the chassis and if so the CV joints will be extended out of spec. It may still work but could cause unforseen complications in the future such as the car crabing when driven. Hope it is not bent though.
 

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I have had many broken aluminum parts successfully welded over the years by skillful welders. As mentioned above, you need to find someone with experience in aluminum welding. With this transmission though, it will need to be completely disassembled for the welding to be done and then carefully machined to make sure the mounting area is restored. There is also the possibility the case will distort from the heating involved for the welding process. Since you have to gut the transmission in order to weld it, you might as well just get another one or an empty case to use for your internals instead. I am sure it would be cheaper and less down time in the long run.
 

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Discussion Starter #15
All right, that's the kind of info I was looking for.

I'm assuming the case would have to be disassembled due to the heat issues and the diference between internal and external medium, right?

I'm pretty sure I know the welder I would use for this, but you're right. If the thing has to be disassembled anyway, it sounds cheaper to replace.

I guess it's time to call my agent and see what options I have there.
 

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Discussion Starter #16
Just to share my suspicions about why this happened. The motor mounts allow some lateral movement within the bushings in them. When the rear wheel hit the curb, it looks like the wheel pushed in and pulled the axle in an outward direction. That's also indicative of the way the rotor broke and the way other things above the axle were bent out instead of in. At the mount, the bushing in the motor mount flexed to absorb the forces, but the angle of the mounting bolts changed inside the casting and blew the casting apart. If the cast area had been thicker right there it may have cracked far worse, or it may have broken something else instead. Hard to say. Something had to give for the force to dissipate. The casting being very thin there, was the weakest point and therefore cracked away.
 

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All right, that's the kind of info I was looking for.

I'm assuming the case would have to be disassembled due to the heat issues and the diference between internal and external medium, right?
To get a decent weld on aluminum, the casting will need to be spotlessly clean and a fair amount of heat will be transferred to the case and internals. You will need to talk to the welder to see what he says, but I would think there are components in the trans. that would not hold well to the heating, but I may be wrong. There are some really good TIG welders out there these days that may work without the excessive heat. For sure any oil or steel parts in that area would act like a heat sink and make it hard to do a good job of welding. No matter what, the transmission will have to come out of the car and I would inspect it very carefully for futher damage because of the side loading it took from the accident. There may be other broken/damaged internal parts as well and it would be disappointing to find the transmission was no good after such an extensive welding job to the case.
 

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Discussion Starter #18
Can someone confirm for me if the transaxle case is cast Aluminum or cast Magnesium?

The master welder I spoke with said he could work with either, but wanted to be absolutely sure he knew which he was dealing with.

His take on the damage was that it should be fairly easy to weld the repair assuming access around that area allows for some excellent surface prep.

He was not concerned about the internals, and said it "should" be easy to keep the surrounding area cool by just welding in short bursts and letting it cool adequately between the welds.

The fact that I got one, really good, welder to tell me he'd do it does not mean I'm ready to go ahead. But, if I can get 2 or 3 other guys with similar knowledge to say the same thing without prompting them with the answer I want, then I may go for it.

"If" I do, "and" I end up with more damage, I'll be sure to let you all tell me you told me so... :(
 

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If the worst that can happen if a welded repair fails is that you will have to pull it out and replace it anyway, you might as well try the welded repair and check its integrity prior to every drive. If you think that a failed repair, gone unnoticed, may lead to more extensive damage, then go ahead and do it right.

xtn
 

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Can someone confirm for me if the transaxle case is cast Aluminum or cast Magnesium?

The master welder I spoke with said he could work with either, but wanted to be absolutely sure he knew which he was dealing with.

His take on the damage was that it should be fairly easy to weld the repair assuming access around that area allows for some excellent surface prep.

He was not concerned about the internals, and said it "should" be easy to keep the surrounding area cool by just welding in short bursts and letting it cool adequately between the welds.

The fact that I got one, really good, welder to tell me he'd do it does not mean I'm ready to go ahead. But, if I can get 2 or 3 other guys with similar knowledge to say the same thing without prompting them with the answer I want, then I may go for it.

"If" I do, "and" I end up with more damage, I'll be sure to let you all tell me you told me so... :(
That is a very positive answer from the welder you found. It shows he is aware of what he is dealing with and what he needs to do as well as the desired result you need. I doubt the casing is magnesium, but it may be an alloy of aluminum mixed with magnesium. The reason he is concerned about magnesium is that it loves to burn by oxidation when heated to its melting point resulting in a spectacularly bright and hot flame with the end result being the metal is turned into pile of white powder. A quick and dirty way to check the case for being made of pure magnesium is to take some shavings/filings from one of the broken pieces and try to light them up with a torch. If they light up with an intense white flame you have magnesium. Also the area of the break on the casting will quickly turn a dark gray color if it is magnesium. If it is an alloy, it won't be as easy to tell because it won't burn as easily. A sure way to tell is to take one of the broken pieces to an aircraft mechanic and have him test it with a kit for magnesium presence. They are used to checking aircraft parts for magnesium content and the test kits are very accurate. As far as damaging the transmission case any more than it already is, I wouldn't worry too much because it is already broken and you really don't have much to lose. As I stated earlier, aluminum castings are repairable, but just make sure nothing else is wrong with the transmission before you consider getting it welded or you may be just wasting your time and money.

The photo below shows a piece of magnesium burning:

images.jpg
 
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