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gazza2006au
01-01-2012, 03:10 PM
im trying to remove the exhaust tube from a outboard the bolt will undo but they are very tight can i use a LPG torch and run it off my BBQ gas bottle to heat the metal around the bolts?

sambino
01-01-2012, 03:25 PM
i don't see why not, as long as it won't damage anything you want to keep it should be fine it may take a bit of heating though, ideally you would typically use oxy/acyetalene, another option is to get a benzo tip or similar with a bottle of thier gas mix which can be found at bunnings but may set you back about $70 or so all up.

PinHead
01-01-2012, 03:50 PM
If you heat the metal it will expand and possibly expand onto the bolts and make them tighter. Try giving the head of the bolts a decent hit first..that quite often works.
Failingthat..try and fresse the bolts to make them contract..yuou can get pipe freeze kits from tradelink.

BM
01-01-2012, 03:58 PM
Gazza,

Heat from your LPG torch will be fine mate. Oxy is better as it is more pinpoint but LPG is fine and I've used it for years to pull out bolts and remove gearbox bearing carriers.

Be careful with it though as the alloy won't glow like steel but if you go too far it will just melt.

Cheers

Stuart
01-01-2012, 03:59 PM
I assume the case the bolts are in is alloy. If so then heat the alloy and then undo the bolt. Use WD or penatrol and leave sit over night then hit it with the heat. Alloy will expand quite a bit but dont use to much heat because you may also strip the threads. If that happens you will need to use helicoils.

Stu

gazza2006au
01-01-2012, 03:59 PM
thanks guys i havent yet purchased a torch im still trying to figure out what one to get i cant afford to buy a oxy kit with bottles so thats out of the question can i use one of those cheap little $30-$40 blow torches?

pig75
01-01-2012, 05:14 PM
Bye your self a MAP torch kit they are about $100 and 10 times more heat than those $30-$40 blow torches

gazza2006au
01-01-2012, 05:52 PM
i went to bunnings grabbed one of the blue fat boy blow torches i got 3 of the 5 bolts undone the other two snapped off where the thread started about 10-12mm is still stuck in there

Roughasguts
01-01-2012, 06:26 PM
Drilling broken studs out ia a pain in the ar$e.
If you get a 12-13mm nut and stick that on the busted stud then drop a weld in the middle of the nut! that will get it out.
Then no need for thread repairs and the like.

Cheers.

gazza2006au
01-01-2012, 07:05 PM
do u think i could get away using 3 of the 5 bolts or i should fix the two broken bolts? i just think its going to be a pain in the ass trying to drill the two broken bolts

PinHead
01-01-2012, 07:15 PM
go back to Bunnings and get some ezy outs..but at times they are not so easy

gazza2006au
01-01-2012, 07:18 PM
PinHead i have tryed easy outs and they have to be the worse tool ever once they snap and they will they cant be drilled out than im latterly screwed

softplasticsdude79
01-01-2012, 07:20 PM
baby oil has worked for me before to free up hard to get bolts,allow to soak overnight

Stuart
01-01-2012, 07:54 PM
baby oil???? Geez mate I can think of at least 100 things I could add to that one.

nigelr
02-01-2012, 06:06 AM
Hot candle wax is very good, believe it or not. Lanolin also.
I'd def be trying rough-as-guts method first up, drilling out studs, easyouts, helicoils can be a real PITA.
Having said that, at least your access looks good, which can be at least half the battle.
Good luck with it.

deckie
02-01-2012, 07:05 AM
Loctite make stuff in a spray can they call "freeze it" or something like that. Tried it and worked for me a few yrs ago but only 6 and 8mm bolts. Can take a few goes. Might be worth a shot.

gazza2006au
02-01-2012, 09:45 AM
im going to try this tool http://www.excaliburtools.com.au/shop/product.php?productid=12&cat=8&page=1 if it doesnt work it will have drilled a nice pilot hole in the center so i can just use a larger drill bit and a tap and die set to retread the hole the bolt is a 6mm what size drill bit should i use if im going to drill out the bolt and retread the hole?

trymyluck
02-01-2012, 11:21 AM
im going to try this tool http://www.excaliburtools.com.au/shop/product.php?productid=12&cat=8&page=1 if it doesnt work it will have drilled a nice pilot hole in the center so i can just use a larger drill bit and a tap and die set to retread the hole the bolt is a 6mm what size drill bit should i use if im going to drill out the bolt and retread the hole?


If your going to try and retain the the same size thread then 5.0mm, start with a smaller drill bit and work up to the 5.0mm drill size. You need to make sure you have it central to the original hole if possible. You should then be able to pick out the remaining thread. But if that fails then you have to decide if your going to retap to a bigger size or go with a helicoil. If going bigger then for 8mm I think from memory is 6.8mm but don't hold me to that.