Advice Please! - Broken Heat Exchanger Stud
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Advice Please! - Broken Heat Exchanger Stud
We've got 1 broken heat exchanger stud and have read a number of posts on the site about removal. I am concerned that all of the other bolts will break if I remove the unit. (photo attached - to show their state). I've been spraying them with a penetrating oil over the last month. I'm trying to decide what the downside is of doing nothing with one broken bolt versus leaving it as is. Advice would be appreciated.
If we end up removing them, second opinion question relates to heating the nuts. Is a propane torch a safe option for heating them for removal.
If we end up removing them, second opinion question relates to heating the nuts. Is a propane torch a safe option for heating them for removal.
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From: indianapolis
studs
i would not drive with one one stud, you will damage the head from the hot escaping gasses down road, it will literly cut the aluminum head.
what penetrating oil are you using??
i will look for the info, but there is a kit out now that is for removal of broken studs. i will get back to you tonite.
frank
what penetrating oil are you using??
i will look for the info, but there is a kit out now that is for removal of broken studs. i will get back to you tonite.
frank
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From: Hermosa Beach, CA
do a search on pelican. there is a guy over there who sells them. I have one in my shop in Indiana but since I am in Cali I can't get it to ship to you. You can do it with the engine in the car but the exhaust system has to come off and you have to have a good drill bit and a careful approach with a measured focus. I had my friend Brent do the couple I needed to do on an engine as he had more experience with drills and sensitive jobs like this.
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From: Atlanta
+1 on driving only at low power settings until that is fixed. You will flame-cut the head if you let hot gas leak out on some full-power up-hill run.
+1 on PB Blaster and the MAPP gas. Propane is not as hot, and the burners are so large it is difficult to avoid heating the surroundings. Get the heat from a pencil-tip burner concentrated on the nut, and get it at least dull red before turning them. You will not break any more studs if you take that approach.
I have forgotton where I got them, but I have a set of left hand drills, which require the drill to be in reverse for cutting. Sometimes you get lucky and the bit grabs and spins the stud out with no need to drill much. Avoid "easy-out" stud removers which insert into the drilled hole. Too many times I have watch people break them off, and then your have a hardened steel part stuck in the stud and no way to drill it out. Remember that aluminum thermal expansion is double that of steel, meaning that the stud will be looser in the head if the engine is hot.
You can fix the stud with the engine in the car, but unless you are pretty confident of your machine shop skills, take that job to a professional and get it done properly. You can't afford to break off a drill in the stud, and you can't afford to let the drill wander into the soft aluminum that surrounds the hardened-steel studs.
+1 on PB Blaster and the MAPP gas. Propane is not as hot, and the burners are so large it is difficult to avoid heating the surroundings. Get the heat from a pencil-tip burner concentrated on the nut, and get it at least dull red before turning them. You will not break any more studs if you take that approach.
I have forgotton where I got them, but I have a set of left hand drills, which require the drill to be in reverse for cutting. Sometimes you get lucky and the bit grabs and spins the stud out with no need to drill much. Avoid "easy-out" stud removers which insert into the drilled hole. Too many times I have watch people break them off, and then your have a hardened steel part stuck in the stud and no way to drill it out. Remember that aluminum thermal expansion is double that of steel, meaning that the stud will be looser in the head if the engine is hot.
You can fix the stud with the engine in the car, but unless you are pretty confident of your machine shop skills, take that job to a professional and get it done properly. You can't afford to break off a drill in the stud, and you can't afford to let the drill wander into the soft aluminum that surrounds the hardened-steel studs.
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From: indianapolis
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We've managed to source Kroil and we're going to try and remove the nuts tomorrow. We also got another product which was recommended to us by a local airplane maintenance shop - it's a Wurth product called Rost Off Ice. We'll try the Kroil first - and have the other as an alternative. Thanks for everyone's input.