Stuck but loose head bolts in a '95 SPX 657X

[67Charger]

I picked this ski up a while ago as a "trailer for sale with free SeaDoo" type of deal. I picked up better ones ( '97 SPX and '97 GTS) after it, so this one needs to go. It actually runs good, barring the residual issues from the Tempo lines that were still installed. Carb kits will cure those ills. New fuel lines are already installed. The issue that I'm struggling with the head bolts. 2 are loose (not touching the head) but seized in place, and 1 is broken off 1/2" down. The head still seals, compression is good, but water leaks from at least one of the bolts. The broken and fully seized bolts are on the Mag cylinder and separated by a bolt. The one that moves a bit is on the PTO side.

Using PB-Blaster, I have one bolt able to work back and forth about 1/2 turn total. Any magic tricks? I know it is corrosion I am fighting, so what seems to work best here?

If I commit to pulling all the bolts out by whatever means necessary, I fear I'll break quite a few and screw the jugs. As-is, the bailers can keep up with the leak no problem. Probably 2-3 oz./minute.

Thanks!

 

[67Charger]

Well, I got one, and the raised but stuck one seems to be able to move back and forth a tiny bit. PB-Blaster and some very light duty heat cycling, along with intermittent raps with a 48 oz. hammer to try and shock it. I am also limiting myself to using a 1/4" ratchet to work the bolt with so I am less able to snap the bolt off in the hole.

The one that came out brought some metal with it, so I ran a tap down the hole and cleaned it out, then cleaned the bolt back to new. Seemed to reinstall normal. I'll still replace it with a new one, but it was reassuring to see it take torque properly.

 

[67Charger]

Fail. Got the remaining stuck one to back out about 4 turns before it seized and snapped. It is no orse off than it really was before, but repair now requires pulling the head. I may just plug the hole and roll with it until it begins to have trouble. Probably not, but tempting.

 

[mikidymac]

Check my HX resto thread. I had to fix 3 broken ones.

 

[Mickirig1]

I took an exhaust manifold to an auto machine shop they pull out the broken bolt. For $20, save my sanity!

 

[67Charger]

OK. I have someone interested in it as-is. I measured the bolt holes and they came in at 9.35mm. This is well within range of a M10x1.0 thread tap, so I tapped the holes with out drilling them out any more and used hydraulic plugs with o-rings built into the bottom of the heads to seal to the cover. No leaks, engine runs the way it is/was, and is no worse off than before. Problem mitigated for $7. Time to move on to working on the skis I am keeping - the '97 SPX and the '97 GTS.