I was thinking of tig welding to build up new material and then mill out new holes in the subframe (engine cradle) to repair the mounting holes for the upper control arm where the bolt hole has been elongated and is now oversized and sloppy. I have the equipment to make this repair, but I am wondering if I need to worry at all about weakening the part at the point of the tig weld in the process of tig welding (and building up the filler material). In other words, will the heat from that process create a weakness in the material at that point (in the existing material). Any suggestions on what type of filler rod/material to use? I assume the subframe is aluminum, but is there a specific type I should use. Any other suggestions or recommendations? On the other hand, Anyone have a used subframe they want to sell at a reasonable price?

 

Sit tight for a minute, this came up once before. Let me see if I can find it.

Provided you'll answer some questions about the headliner, that is.

 

Below is the first and only time I have read about your problem. Follow the thead through to see if it gives you any better options, and please check the "sagging headliner" thread for my questions:

https://www.jaguarforums.com/forum/s...ht=crossmember

 

To answer your question; Technically yes spot or fill welding of aluminum will cause localized brittleness. Typically after welding aluminum it should be heat treated or annealed to revert the entire welded assembly back to its specified strength properties.

The real question is: would it be enough of a metallurgic change to adversely affect what you are trying to accomplish. Unfortunately you probably wont find an answer to that question.

As a former fabricator & welder and having an idea of what you are faced with; If it were me I would weld it. BUT if I were to pursue this I would have to be prepared to buy and install a new one if it failed because the process could possibly make the condition worse.

I'm only saying here what I would do in this scenario! Good Luck.

 

Greetings RJK,

Thanks for your expertise. The way I see this problem, welding and reboring the crossmember would be impossible without its removal from the car.

I think the bush idea is a sound one, particularly since the throughbolt does not rotate in the crossmember by design. Resizing the holes without decreasing the strength of the mounting location is the only concern, so a small increase in diameter is all that is necessary. I'm still inclined to think that a thin wall bronze or steel bushing would be a permanent and less labor intensive repair.

 

Any thoughts on where I might find a bushing of this sort? I see davef in the other post solved the problem in this fashion, but he apparently checked out and I can't get a response from him as to what specific bushing he used. Not sure where to go to get bushings by size, as opposed to application. Any thoughts appreciated.

 

This is not a problem I have encountered. I would imagine that a supplier such as Grainger's would have a selection of sized bushings of various compositions to select from.

I'm thinking I would look for a line reamer first, that would insure the holes are correctly resized and would determine the outside daimater of the sleeve required.

 

I would think a tool and die shop would be able to fabricate what you are looking for. I would think they could even leave a step at the insertion point so you could tig that to the housing. Picture a large billet aluminum rod that they would first bore to your spec. Then on the exterior of this now bored billet they would then turn down the outer wall to fit what you need on the car. While they are turning down the billet they could leave one end with a head of sorts that you could tig to the car. Thus they will have essentially build you a sleave. Weather it is an aluminum billet or tool steal let them decide just tell them what you are doing and they could advise you. Remember you are looking for a small tool and die shop. A big one probably would send you packing. For sleaves I would look at McMaster-Carr over Grainger.

 

Here is a page from Mcmaster Carr that my help.
http://www.mcmaster.com/#sleeve-bearings/=3r8qre

 

I know this is an old tread....but I am having the same issue with sloppiness in the engine cradle that the upper control arm bolts to. I'm just wondering if a solution was found? I don't want to spend a ton of money on this car. I have a licensed mechanic looking at it. I am just wondering about possible and easy ('ish) way to sleeve it without days of work.
any advice is really appricated.

 

I'm not sure about the "easy" or "quick" solution, but I ended up purchasing a used subframe (cradle) from someone on Ebay, then I bought a rolled XKR (complete), and I will probably still look at the sleeve option (if for nothing more than as to recycle my existing subframe (whether I put that one back in, or one of the other two). The dealership wanted $3K for just the subframe (cradle), and like $7K for the complete job. I assume the quote included bushings, etc... but you can pick up a front end kit for a few hundred from a site in the U.K. Anyway, the "easy" way I think would be to try bushings, but that still requires some work. I haven't done mine yet. Driving another Jag at the moment.

 

Thanks for the advice. I am just concern with the accuracy involved in drilling and installing a bushing or a sleeve.
Nothing about this sounds easy.

 

One guy was talking about doing it while it was still in the car, but I would probably pull it, and then drill and sleeve it. I have the tools available, but I don't think you'd need much to get it done right. I guess it depends on how bad the holes are elongated. You have to be careful because trying to fill any lost material in the original part (the magnesium) will potentially make the cradle more brittle, or otherwise change the temper (from heating it up from TIG or MIG welding it). Again, it is going to depend on what condition your existing part is in, and whether it is a simple process of drilling the hole out a little bit and then adding a sleeve, or whether you need to replace the entire cradle. Take pictures of the holes if you end up removing the cradle and post them here, or send them to me. If your mechanic isn't comfortable dealing with the cradle once he removes it just run it over to a machine shop (just don't tell them it's from a Jag or they'll triple the price)...

 

great advice on not tell them its a jag. My mechanic is hoping to do it in place with an angle drill. We still don't have it apart. We just started talking about potential solutions to the problem. We think the bushings are siezed too, so we are going to have to cut the bolt to get it out. I don't think there is a ton of play, but I guess the only way to tell is too take it apart and go at it.
I know he isn't too keen on taking the whole cradle out. I guess we'll see. I'll defiantly take some pics and post it on here.
Thanks for your advice

 

Reworking suspension mounts adds the problem of alignment. Without a jig of some kind, you are guessing on the rebore of the holes after welding up. Just make a drilling jig to fit over the frame so the new holes will align with the original, if you can determine that. If the holes are really that loose, I would consider replacing the whole thing with a good one from a junkyard.

 

I originally drilled the hole out slightly and used an oversized bolt. The play went from 3/16" to less than 1/16". Told myself I was going to watch for corrosion between the steel bolt and aluminum frame but the problem came back in about 10K miles (bushings / alignment?). Bought a subframe for $300 on eBay (after confirming the holes were'nt elongated) and took it to a reputable body and alignment shop. They broke both engine mounts ($300 expedited), I think you are supposed to heat up the Loctite which of course they didnt. Found a popped engine mount ($100) and had them replace the Upper wishbone bushings and ball joints I provided, as well as the bolt and nut from Jagbits (total about $250). About $850 went for the subframe install and alignment. The clunking went away but now i had a high speed rattle in my steering wheel (pretty bad) that I had never had before. My body alignment guy had had enough - said it was my tires and rims. Found an Indy Jag repair to replace the lower bushings and ball joints, and replaced the shocks as well because they cost the same as the shock bushings (about $400 parts and $300 labor). I had already replaced the steering bushings. Everything was supertight with a little road noise, replaced the tires and precision balanced and front end is like new. Painful but a lot less than going to the dealership and I had forgotten how sweet the car is to drive when its correct.

 

I meant to say the bodyshop broke both the subframe mounts.

 

All I can say is WOW, way to hang in there! And you're right, they're incredible when well-behaved. My suspension and power train are just getting there now after seven months of sorting out.

 

Wow is right. your making me wonder if I am doing this the right way. The sub frame I found is $500 plus shipping. My mechanic thinks its ok the drill and sleeve the aluminum because he doesn't think its that bad. Keeping the holes centered it the biggest hurtle I see. I have a new bolt from Jag and new control arm bushings too.
I am hoping to have better luck than thenaz007 (the drilling part) . I am getting 2 sleeves made a machine shop today with 2 small flanges on the end of them to keep them in place. I will be bringing the bolt ofcource and as long as we drill to the outsside diameter of the sleeve....then everything should be fine.

 

update-
I ended up taking the engine craddle out, and having the part professionall machined. They did a great job on it. Its back up in place. I lost the order of washers and shins, so today i am trying to sort that out. does anyone have parts numbers and a picture of how it supposed to be assembled?
I am close anyway and I think it will all have to be redone for alignment