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I am considering everything to prevent myself from having to replace my timing cover. I have no idea how this happened but the A/C compressor snapped a part off my timing cover. I looked at the compressor and the compressor mounting bolts and one is missing, one stud is snapped in the other side of the timing cover and the other one is the one that broke. I personally think he was running this thing with 1 bolt! Anyway, I have been doing research on aluminum brazing rods. I know the motor is cast aluminum and I have heard great results from others in welding forums. I figure that it is worth a try as long as it is done right. Has anybody tried this? The aluminum that broke is very thin to begin with. With the three bolts in correctly, there should be very little issue. Thoughts? I have attached a picture of the break. The right is the part that is still on the AC pump and the left is where it broke.
The brazing rods are also stronger then the aluminum and tig welding. It’s more like soldering with a torch. It’s not welding. Look up Blue Demon or HTS2000 brazing rods. I think with the other two bolts in place it would hold well
you will do more collateral damage with the torch than you think,,, tig weld would be better if you can get access to the area if you know someone who is good at it. .... I would consider fabricating a sturdy bracket and attaching to another solid mounting point allowing your AC to sit where it was,,, guessing someone did not reinstall the 2nd bolt and you got the worst if it when the compressor twisted, if you want to do it right and keep factory OEM look then replace the cover as centerline mentioned -
Aluminum is harder to braze than people make it sound. If you get it clean enough, and hot enough, It is likely the sealer will start leaking. Aluminium transfers heat instantly. You might as well give it a try so you don't forever wonder if would have worked. Keep a chemical fire extinguisher handy
You can't just stick it on with something temporarily and use a slightly longer bolt? As long as the other bolts are installed, the forces on that area should be virtually nothing. All you would need is 3-4 good threads left past the break (use thread locker and don't make it very tight).
Obviously replacing the cover is the "best" route, but that's a lot of work so I would definitely try some repairs first.
I wouldn't recommend brazing that. I would worry about cooking the sealant and causing leaks and/or setting some oil or hoses on fire because it will take a LOT of heat to get that thing anywhere near hot enough to braze (and no matter how well you clean it, there will be oily residue left in places). It might be possible to braze that successfully, but I wouldn't want to risk it. Maybe with a lot of experience, but the amount of heat you would need will make that extremely difficult to pull off.
Personally, I would TIG weld it with just a few tack welds to prevent getting it too hot. It shouldn't be hard if you can get the tig torch in there... probably won't even need any filler.
TIG welding is much stronger than brazing in most situations. There are certain cases where brazing can be stronger, and I suspect that this might be one of them (brazing should join the entire broken surface while welding will just join it at the outer edge), however, strength is a non-issue in this case. If either process is done half-way right, the repair would be far more than strong enough. In this particular case, TIG welding should be easy, whereas brazing that (even with a lot of experience) would be extremely difficult. Even if it didn't go very well, TIG welding this would likely be successful, whereas brazing would need to be done properly in order to work.
If you can't (or don't want to) TIG weld it, you might even try JB weld as a last resort. Sure, it may fail, but I've seen it hold on similar things with much higher stresses than that and you don't really have a lot to loose. Just make sure it's VERY clean first and give it at least a full 24 hours to cure.
Whichever way you go, use a slightly longer bolt afterwards to catch the threads past the break.
Great write up and I appreciate everybody’s help. I’m not quite sure what I am going to do yet but I do know that the oil lines and coolant hoses are going to be removed and replaced. I was also thinking of putting aluminum foil or a fire resistant material around the brazing area before even trying. I was also thinking of doing the brazing with the bolt in place (if I can) to get even more threads for added support.
Can you use a longer bolt, or longer and thinner, and a nut, maybe grind the nut into a triangle shape or a smaller nut for the smaller diameter bolt, or something to fit back behind where the piece broke off? Put some loctite on it and don't over-tighten it, or use a nylock nut, that and the other 2 bolts might work.
Brazing is a totally different thing as the word is a contraction of brass. Some marketing of the product might call it that. What you are thinking about is aluminum soldering. That’s a glorified glue job. Take off the cover use a TIG and fill in some of that top area and make it stronger than OE. Sometimes anticipation is harder than the job. Do it right or better the first time so it won’t come back.
I think it is difficult to use in vertical or out of position applications. When they say it is stronger they mean the filler material has higher tensil strength than most aluminum. In order for a repair to be stronger and equal thickness of that material would have to be applied in all places. This usually requires the ability to have access and position to perform that task, not likely in your situation.
Last edited by aircommuter; Oct 12, 2018 at 11:19 AM.
Reason: spelling
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