Busted bolt stuck in my cylinder head, do I dare heat it with a Oxy/Ace torch?

[Johny25]

Ok so I decided to replace my thermostat in my 88' Johnson and the bolts holding the cylinder head cover were seized in there. I got all but one to come out and just so happens that the one that snapped off was the one most difficult to get at. I got the cover off and there is now about 1/4 of the bolt sticking out of the cylinder head. I cant get an easy out or drill to it unless I remove the cylinder head or drill an access hole through the back of the bottom engine cover. Both of which I don't want to do. And easy out is not going to get this bolt out anyway (I hate easy outs). I have soaked it for 2 days in penetrating oil and attempted to vise grip it loose to no evail. Now I am debating getting the Oxy/Ace torch out to heat it up and give it another try. Is this a terrible idea given it is an aluminum head and may warp the head? I mean I know I could warp the head but has anyone done this successfully or am I just better off to bite the bullet and pull the cylinder head and drill and tap it out? I have good compression so I didn't want to pull the head. The busted bolt is hard to see but it is at the end of the screwdriver in the pic.

 

[F_R]

Re: Busted bolt stuck in my cylinder head, do I dare heat it with a Oxy/Ace torch?

I can't make anything out of the picture, but I can tell you that I have removed literally thousands of bolts with the aid of an oxy/acetelyn torch. An outboard mechanic can't live without one, especially in a salt water area like I am.

It won't warp the head. Melt it? Yes, if you aren't careful. You want concentrated heat on the metal right around the bolt, as hot as you can get it without melting it----or anything else close by.

BTW, thanks for rejecting the Easy Out thought. I hate them too.

 

[Johny25]

Re: Busted bolt stuck in my cylinder head, do I dare heat it with a Oxy/Ace torch?

Ok I am going to give it a whirl, I am very competent with a torch and know the melting point of aluminum. Spent many years as a welder fabricator (aluminum also). Here is a better pic prior to pulling gasket material and cleaning the corrosion. It is the rusty orange thing sticking out in the bottom of the pic.

 

[boobie]

Re: Busted bolt stuck in my cylinder head, do I dare heat it with a Oxy/Ace torch?

Go for the oxy/ace torch and as F_R said if you have any easy-outs throw them away.

 

[Mas]

Re: Busted bolt stuck in my cylinder head, do I dare heat it with a Oxy/Ace torch?

You could also thread on & try to weld a nut to the end of the bolt.

Mas

 

[sutor623]

Re: Busted bolt stuck in my cylinder head, do I dare heat it with a Oxy/Ace torch?

Those bolts that are hardest to access always seem to be the first ones to snap dont they? I pull my powerhead for a lot of my motors so that I can get an airgun to it, and it still snaps bolts sometimes. Once I have worked on a motor once, the bolts always come out easier next time since I use anti-sieze where applicable.

 

[Johny25]

Re: Busted bolt stuck in my cylinder head, do I dare heat it with a Oxy/Ace torch?

I was considering welding a nut on it Mas but I got it out with the torch, vise grips and channel locks to clamp the vise grip really tight. Thanks for the info FR about not worrying about warping the aluminum head I actually trashed talked my motor in the shop after the bolt came out lol..... It is the small victories sometimes that mean the most.

And totally right Sutor, it is always the absolute last bolt that you want to snap off being the one that snaps off....aarg. And yes everything will be going back on with anti seize. This motor had never had the thermostat/cylinder head cover off, still had the factory paint on it.

 

[Mas]

Re: Busted bolt stuck in my cylinder head, do I dare heat it with a Oxy/Ace torch?

Great news...but do not trash talk too much, those bolts can make our lives more miserable than we can make theirs.

Mas

 

[AlTn]

Re: Busted bolt stuck in my cylinder head, do I dare heat it with a Oxy/Ace torch?

from the looks of that second pic it may not be long before you're trash talking the head bolts...just sayin'

 

[durban]

Re: Busted bolt stuck in my cylinder head, do I dare heat it with a Oxy/Ace torch?

no sweat no fuss , if you can get i vice grip on if not ,tig weld a washer on & then tig weld a nut on to the washer , before you do all that drill a 1.5 or 2mm hole next to the stud ,in other words between the aluminum & stud measure the depth of the thread with one of the other studs then you know how far to drill down , then take NITRIC ACID & put it down the hole & leave for a few hours , then bobs ur uncle , it comes out no problem , drill 2 holes opposite each other . cheers

 

[sutor623]

Re: Busted bolt stuck in my cylinder head, do I dare heat it with a Oxy/Ace torch?

And totally right Sutor, it is always the absolute last bolt that you want to snap off being the one that snaps off....aarg. And yes everything will be going back on with anti seize. This motor had never had the thermostat/cylinder head cover off, still had the factory paint on it.

Great news bro, I'm glad you got it out. Man life never seems to be that easy for me......

 

[Johny25]

Re: Busted bolt stuck in my cylinder head, do I dare heat it with a Oxy/Ace torch?

Well AITn I won't have to venture down that road just yet being that I got that darn bolt out And I think it says somewhere in the forum rules to never speak of another mans head like that

 

[AlTn]

Re: Busted bolt stuck in my cylinder head, do I dare heat it with a Oxy/Ace torch?

something about living in glass houses and casting stones?...just had my first experience with having to drill out a head bolt < it broke below the surface of the head>...I hope the overheat is cured on yours, but if it isn't...your experience with the heat will be of great benefit to any head bolt somewhat more reluctant to loosen than the others

 

[Johny25]

Re: Busted bolt stuck in my cylinder head, do I dare heat it with a Oxy/Ace torch?

Well that sucks to hear AITn, did you get it out? I didn't have a problem with over heating, my thermostat was stuck open and my motor wasn't getting to operating temp. That's why I had to pull the cover off. If mine had broken below the surface I would have had no choice but to remove the head to drill it out.

 

[AlTn]

Re: Busted bolt stuck in my cylinder head, do I dare heat it with a Oxy/Ace torch?

yeah...got it out..moved up 3 sizes with right hand bits then a left hand bit "caught" and the old threads from the screw wound out clean as a whistle

 

[Johny25]

Re: Busted bolt stuck in my cylinder head, do I dare heat it with a Oxy/Ace torch?

Nice, I am glad to here you got it out The drill option was exactly what I was going to do if I had to remove the head.