10 out of 10 head bolts broke off!

[tx1961whaler]

Re: 10 out of 10 head bolts broke off!

I wasn't talking about tapping the head off. I was talking about beating the ever-loving crap out of it to break it loose from the bolts. You can also use some heat, and a large punch to sharply hit the bolts (don't break the powerhead!) to also break their grip. I've had to do this operation a few times (salt water...) and haven't ruined anything yet. That may just be lucky.... :redface:

 

[cadet917]

Re: 10 out of 10 head bolts broke off!

yes i saw that on ebay... i am gonna wait till i have this one off before i buy anything.

 

[jbjennings]

Re: 10 out of 10 head bolts broke off!

If I were you, I'd take it to a machine shop and let them have the headache of getting the head off and the bolts out. THey're experts at this type of thing and it would be better to spend a few dollars to get it done right vs. ruining the motor and having nothing. Just take the powerhead off and take it to them. If they want more than $100 bucks to take them off, then save yourself some money and buy a used powerhead off ebay. I'll bet you could find one for around $100.
JMO,
JBJ

 

[wilde1j]

Re: 10 out of 10 head bolts broke off!

i do have a 135 amp lincoln welder so ill try that. id prefer to get the head if first if i could tho. i think i will replace the bolts with studs and cap nuts if i get these all out.

Forget the studs and nuts, the bolts are typically ss, and I would replace with the same as original. In any case, I'd be inclined to get another powerhead, since something clearly must have been wrong with yours to want to pull the head. If you ever get it apart, you'll clearly have a very large time investment. I don't think any "magic" solvents are going to help in this case. JBJ's thought of using a machine shop is pretty good also.

I've broken water cover bolts, but never a head bolt, but I've been quick to put the serious heat to stubborn PH fasteners.

 

[bob johnson]

Re: 10 out of 10 head bolts broke off!

each person is different....finance wise and work effort vs quality of life wise.

for sure you are going to have at least a few oblong holes in the end.....if you cant get the broken bolts out even if you get the head off and go to drilling....I just dont see you doing 5 or more straight!!

you got to make sure you dont break the tap...because then you will take it to a shop for repair.

heat is your friend now....soaking...might work..

the best stuff is called KROIL...stinks like crazy.....

heating the head and tapping all around on every edge you can get a punch...working all around constantly...if you try to pry it..you will mushroom the soft aluminum and might destroy the head and the block.

I would imagine a 10 hp motor cant be worth all this effort you have ahead of you...unless you are just bored at home these days.

keep it for parts and move on

bob

 

[rjh1936]

Re: 10 out of 10 head bolts broke off!

There is a welding rod called extract-alloy that is made especially for this problem. It is designed to weld onto the top of the bolt and the directions come with it. Basically it says, this rod is designed for this purpose and it can be used to weld onto broken bolts even down in the block. The special flux will protect the thread. It has some titanium to make it strong. Set the welder at the lowest power that you can start the weld. Put the rod straight down and weld onto the top of the broken bolt. Build the weld up to above the block surface and make a little protrusion, Weld a washer onto this protrusion. Weld a nut onto the washer, Let it cool. Remove bolt with wrench. If it breaks, do it again. What happens is this. Welding the bolt causes heat that expands the bolt. Because it is encapsulated in the threads, it can't expand. When it cool, it shrinks and is now a smaller diameter, which allows it to come out easily. A friend gave me some after I had 30 ?? bolts break off in an outdrive because anti-seize had not been used. I removed all very easily this way. Talk to your local welding shop, as there may be more than one manufacturer of this. Good luck

 

[jonesg]

Re: 10 out of 10 head bolts broke off!

theres a bit more to it, it needs hammering with a drift every now and then to harden it, plus remove the slag from the weld as you built it up.
theres videos on ebay about this.

 

[bob johnson]

Re: 10 out of 10 head bolts broke off!

so it appears as if the prognosis is bleak for this motor for the OP.

10 out of 10 successfull back yard broken bolt repairs??????

I broke 4 off in the block of my 1988 70 hp. But i stripped it and set it up on a bridgeport to make sure i could drill them out straight!! and controled...if you drill by hand the drill wants to walk over into the aluminum!!!! and you get a hole at an angle that starts out in the center of a broken bolt and end up over in the aluminum at the bottom!

If it is a SPORT TWIN...then I am thinking it is probably 30 years old or more...

cant be more than a $300 motor most places...and for sure right now it is a $50 motor....

to some that make it worth while( no loss really) to others it makes it a no bid repair( aint worth the effort)

you will probably need to machione the head after wards...because it most likely wont be flat after it comes off...

then you have to think about what made you decide to take the head off in the first place?? low compression?

I started working on my 70 hp( salt water motor) and the preject kept going and going and going...to the point that every piece of the motor had been removed to all other pieces!!!!

( hope i remember where all those pieces are later on!! ha ha)

best of luck.....not un doable.....but a tough road ahead for sure...

even if you had all the experience of the repliers combined!!!

bob

 

[wajajaja02]

Re: 10 out of 10 head bolts broke off!

propane wont be hot enough,go with mac or acetylene

 

[cadet917]

Re: 10 out of 10 head bolts broke off!

the motor is a 1960. it sat for 10 yrs and i had it running in 2 hrs. when i ran it it water i was getting water in the lower cylinder so i attempted to take the head off to replace the gasket.

 

[jonesg]

Re: 10 out of 10 head bolts broke off!

put the plugs back in, crank it with a healthy battery, that might pop the head loose.

If you get the head off the studs will be easy to deal with by using direct heat or welder.

 

[cadet917]

Re: 10 out of 10 head bolts broke off!

its not electric start but it will start within 3 pulls guaranteed.

 

[SKEETR]

Re: 10 out of 10 head bolts broke off!

Try pulling the spark plugs and inserting a section of rope into the cylinder. Then just wrench on the flywheel bolt to apply pressure. Might work???