Products/techniques for frozen head bolts

[mattsaks]

All but two of my head bolts are seized. Do they usually corrode into the head itself? Or is it the threads into the block? i will try some heat but am worried that even if i break off the bolt heads the head will still not come off. Is there a good penetrating spray that would help? Any other things i should do?

 

[P.V.]

Re: Products/techniques for frozen head bolts

I use OMC/BRP "Engine Tuner" with mild propane and lots of patience!!! And then more of the same!!!

 

[Solittle]

Re: Products/techniques for frozen head bolts

matt - iboats has a neat feature that many overlook that I suggest you try. Go to the red search at the top of the page and enter "broken bolt". Read what others have done.

 

[mattsaks]

Re: Products/techniques for frozen head bolts

Thanks. I'm not to worried about removing the broken bits, its only if they have corroded into the head I might not be able to remove it! Maybe i'll have to get the drill out...

 

[jim dozier]

Re: Products/techniques for frozen head bolts

Yes. Yes. You should be. Yes. Yes.<br />To elaborate, the bolts may be frozen in the threads, they may be frozen on the shaft in the head, or both. I had a similar problem with my outboard. Using heat and PBBlaster I still snapped the head off of a headbolt. Even with all the other head bolts out and the head off of the broken one I had to beat the #%&# head off with a rubber mallet. The shaft of the bolt had corroded in the bolt hole in the head. It is amazing the grip that salt water corrosion can have on the smooth shaft of a bolt. Once I got the head off I was able to unscrew the remnant of the bolt with my fingers. If you are going to work on a salt water outboard you need to get familiar with a tap and helicoil, and methods for extracting frozen bolts, because they are commonplace. Penetrating oils like PBBlaster are useful but very often as in the case I described the corrosion is too far in from the surface to be reached by any penetrant.<br /><br />Use heat first not as a last resort. Do NOT use EZ-outs as the grip of corrosion exceeds their breaking torque and you will need to learn to extract the extractor. Use the penetrating oils. Use a impact wrench. Use patience. Use a drill, grind the stub flat and center punch and start with small drills and work up to bigger ones. Use a Dremel or similar high speed rotary with a carbide bit (like a tile grout bit) for keeping holes centered if they drift offcenter.

 

[jleus]

Re: Products/techniques for frozen head bolts

I have had luck with getting the head (or cover or what ever) off and fastener out by removing the head of the bolt. It does require some beating as described above to get past the corrosion between the bolt and the piece sometimes. Cut the length of the bolt down to reduce the loss of tourqe from the fastener twisting and find a nut of what ever deminsion such that the shaft of the bolt fits in the ID of the nut. Cut the length of the remaining bolt with the nut being welded on in mind. Give it a few hours or days of soaking with the penetrant of your choice and then weld the nut on to the bolt, and I mean burn it on there. I prefer it stick welded at some pretty good amprage. Get the bolt red hot as best you can with out melting down the bolt or losing the hex of the nut. More penetrant and that heat the steel went through ussually gets the corrosion to let go. I think the heating and cooling of the steel hardens somewhat what is normally soft material. If you break the bolt of flush with the surface of the threads its a whole different ball game.

 

[rodbolt]

Re: Products/techniques for frozen head bolts

oxygen/acetylne. propane is usually not hot enogh for saltwater engines. I agree with jimd. he must see them old suzuki's but all the motors will have stuck fasteners eventually. <br /> some motors I have had in the shop we were lucky if the hood came off.<br /> good luck and keep posting<br /> PS the welding trick works. there is also a special rod made for stud removal. its about 90 dollars a pound but works well.

 

[mattsaks]

Re: Products/techniques for frozen head bolts

Thanks for the ideas. I will try welding on the broken ones as i have been successful in the past using that method. With the unbroken ones, should i heat the bolt or the surrounding area?

 

[rodbolt]

Re: Products/techniques for frozen head bolts

the surrounding area. actually heating the bolt makes it softer. its a game I play daily.<br /> good luck and keep posting

 

[novicetech]

Re: Products/techniques for frozen head bolts

You might also try to tap on the head of the bolts with a hammer and brass drift, sometimes this method will turn the corrosion into dust, then the bolts will come out.

 

[Scaaty]

Re: Products/techniques for frozen head bolts

Originally posted by rodbolt:<br /> some motors I have had in the shop we were lucky if the hood came off.<br />

ROTFLMAO! Amazing the "Maintenance" so people do!

 

[rodbolt]

Re: Products/techniques for frozen head bolts

well it worked for 15 years so we did not do anything to it. I hear it daily. and I tell them we may not do any thing now either. <br /> good luck and keep posting

 

[mattsaks]

Re: Products/techniques for frozen head bolts

thanks for the ideas. i will take it into work so i can use the gas on it!! will let you know how it goes...

 

[rodbolt]

Re: Products/techniques for frozen head bolts

hello<br /> another trick I should not tell. sometimes if I can access the bolt at a 90* angle I will drill a 1/8 hole through the casting to spray penatrent on the bolt. normally its the corroision around the shank not the threads.<br /> good luck and keep posting

 

[mattsaks]

Re: Products/techniques for frozen head bolts

even if it was a head? do you weld up the holes again?

 

[rodbolt]

Re: Products/techniques for frozen head bolts

nope<br /> not if you drill just from the side perpendicular to the bolt. there is no water passages there so its no worry. if you worry about cosmetics epoxy the hole and paint it when done.

 

[AMD Rules]

Re: Products/techniques for frozen head bolts

Sounds to me like a good spot for the manufacturer to install grease zerks at the factory. That way, for these larger horsepower offshore motors, the end user could lubricate the shank of the head bolts with anti-sieze compound as part of scheduled maintenance routines. Salt water corrosion is common in marine applications. Removeable head bolts are a must.

 

[mattsaks]

Re: Products/techniques for frozen head bolts

well.... i pulled the powerhead and took it into work. with heat etc i managed to free up/ remove seven of the head bolts!! head is still stuck on tight so i guess im going to have to drill out the remaining broken ones untill it comes off. anyone used lefthanded drill bits? i have heard they are good for this??

 

[rodbolt]

Re: Products/techniques for frozen head bolts

hello<br /> in your case a left hand bit will be usless. I use the cobalt/tin bullet point bits. try to find a transfer punch of the proper size to center punch the stud with. then use the tap drill size and drill almost to the block. try to leave a small part of the stud exposed from the block for stud removal. its normally the shank that is stuck.<br /> good luck and keep posting

 

[mattsaks]

Re: Products/techniques for frozen head bolts

Well its coming along, but very slowly. i have drilled all the bolts to about 5 mm from the block and it is still as tight as ever! i dont want to hit it to hard and break it. guess i need to go a bit deeper. does it matter if the holes through the head end up a little larger?