1987 Ferrari Testarossa Head removal -Stuck bad!

Looks like we have a hacker/highjacker from India. ^^

 

I have encountered similar situations when rebuilding old Ford flathead sprint and midget engines. What was really holding the heads on was the corrosion around the studs. Which is basically aluminum oxide. The first thing that most people do is immediately spray the area down with penetrating oil. This would be fine if you were dealing with all ferrous materials. As most penetrating oils are formulated for use on ferrous oxide. Applying penetrating oil to aluminum oxide basically seals the oxide preventing one from dissolving the oxide, which is really what you need to do. If you have already soaked the living daylights out of it with penetrating oil you are often left with the only alternative of brute force. In reading through all the posts so far the most promising to me would be the ultrasonic, failing that would be EDM (electro discharge machining). The common use for EDM is removal of broken thread cutting taps. Your situation isn't that far removed.

 

^^^ This ^^^

As a Ph.D. chemist, IMHO with the proper solvent, there is a reasonably good probability of the high frequencies allowing penetration and/or stabilization of the dielectric encrustation. Perhaps after this treatment, the aforementioned methods will work without damage.

Give it a shot, it can do no damage to the engine and is not excessively expensive.

 

Oh crap! I thought I was the only one on here!

But I just made a bunch or organic tars to get my degree. Can't help with the corrosive properties of dissimilar metals.

Wish the OP much lick and no engine damage. Waiting to hear what eventually "be-heads" the block.

 

This is great information. It's always remarkable how much I don't know.
Is there nothing in a spray can that goes after aluminum oxide?

 

Aluminum oxide is soluble in acid but using that isn't a good idea for the surrounding metal. It is also soluble in bases, so perhaps an alkaline cleaner with a surfactant to help remove any oil coating the oxide will work.

 

Shear strength of the oxides when taking into account the surface area involved of the studs can really add up.

Consider ~ 12mm stud / ~75mm corroded engagement length / 500psi shear strength of oxide (probably a very low estimate) gives 2,300 pounds force to yield. Now multiply by number of studs, and bending tools makes too much sense. A really stout, carefully engineered fixture sounds like a good help.

I would add: Before another attempt to separate, get hold of a plastic rod of polycarbonate or PEEK, say 5/8 - 1 inch diameter by a foot long and with all of the studs well soaked in Liquid Wrench (My favorite for this), smack each stud via the rod for ~ 5 minutes. The hope is to disturb the brittle oxides which in this scenario is good, and allow further penetration of the Liquid Wrench. The stud threads may be harmed, and if you want to provide more protection from the plastic, a sacrificial piece of leather will help.

I feel for you. Let us know how it's going.

 

psk (pete) is correct,a jig must be made to remove this head,my tr had the same issue(10000/miles no use),get an engineer and pay for a job you cannnot handle,my mechanic still has his jig ,but im too far away to help
all the best
tom

 

I don't have this problem but if I did, i would drive it down to my friendly welding shop (there is one shop one mile from where I live with a bunch of guys just standing around all day), ask the head honcho guy to see if he wants a challenge, and pay him $500 to weld up a jig that will pull that baby off.

I do a lot of things by myself but there are limits to my skills and equipment. I don't have the skills and equipment for this kind of work.

By the way, around my neighborhood, there are tons of car guys with lathes, welders, and mills at home. There is one (I just found him) with a full machine shop in his basement. Is there anyone like that in your neighborhood?

 

This idea may be a little drastic, but there is a technique called Electro Arc Metal Disintegration that is used to remove broken bolts, taps, etc. Here's a video of the technology in use:

[ame]http://www.youtube.com/watch?v=FgDscaUOQnc[/ame]

You could find a specialist by Googling "Electro Arc Metal Disintegration" and have them "burn" the studs below the head/block junction, then remove the heads and "burn" the studs out of the head. I would think you would find the most experienced shops using this technique in Huston or in the upper Midwest.

If I remember correctly, Lindsey Publications has a book on building your own metal disintegrator if you are so inclined.

 

There is only one safe and reliable way to do this and it involves a little engineering but only requires a vertical or pillar drill. Remove all the head nuts and washers. Take a piece of half inch thick steel plate, approximately the overall size of the head and carefully mark out the positions of all the cam bearing cap studs, cam cover studs and cylinder head studs. Drill the cam cap and cover stud holes with a clearance drill bit and drill and tap the head stud positions to anything close to 10mm fine thread, M10X1.0 or M10X1.25 or even 3/8in UNF. Fit long hexagonal machine screws (full thread, 100mm if you can get them) to the tapped out holes and place the whole thing on the stripped head, holding the plate down with all the cam bearing cap nuts and flat washers. Wind all the long screws down to contact the head studs and then slowly torque them up, one by one and in the normal sequence. Penetrating oil, patience and a lot of time under tension will see the head slowly come away from the block. If you run out of thread, back the screws out, hammer the head back down with a large rubber mallet and pull it up again until the corrosion between studs and head is loosened and the head should come off with a good tug. If your plate is a little short, you don't have to push against all of the 14 head studs. 8 or 10 should be enough and if you apply a little grease to the tops of the studs they might even remain undamaged. Good luck,
Chris

 

Ferrari, threw a big wrench in your plan. The head studs on the TR are hidden inside pockets, because of the location of the camshafts, there's no straight shot to push against them as you suggest.

 

I think the pockets rules out EDM or elecrto arc disintegration!






Ago

 

Other than a pulling fixture and use of something other than oil to dissolve the corrosive bond I see few good or safe ideas here. Perhaps EDM if the surrounding material could survive.
"blowing" it off by detonating a mixture in the cylinders may be catastrophic as I suspect the weak point will NOT be what's expected by the author of that idea.

 

Yep as you can split the block this is really not that hard. I've already detailed my suggestion using a shaft where the crankshaft would have been ... yeah it will cost a few beers to make but will be very strong and off the head will be pushed.

There are few short cuts ...
Pete

 

will the pistons come out the "bottom" of these?

 

Is there not room for a piece of steel bar sitting on top of pairs of adjacent studs, lying across the head? Then the hex screws can bear against this instead of the top of the studs. This would only require repositioning of the hex bolts on the extractor plate to a position above the bar.
Chris

 

I understand the 'straight-line' traps in stud access, but are there enough to maybe push on (whatever enough is??).

I like the idea of splitting the case and pushing on pistons; but, my big concern is cyl head combustion chamber may not like it. Obviously this would risk pistons, liners and the unknown.

This is really not cool! What's the status now? Best of luck.

 

4 or 5 bars resting across adjacent pairs of studs should do. The extractor plate can be anything from 1/2inch to 3/4inch thick to allow the cam cap nuts and washers to go on and after use it can be kept and redrilled for V12's which need identical treatment!
Chris

 

I expect this picture will help future generations of techs working on these issues. Thanks for dropping that off.

 

Remove cams so all valves are closed, fill cylinders with water, turn crank by hand and a long pull handle.....

 

Congratulations!

You did exactly as I recommended.

Take some good photos and post for future reference.

 

I've been following this, but with no technical insight into the issue, I didn't want to comment. All I can say is I hope to never have this problem, looks like a pretty crazy device you created and made work.


Congrats!!

 

Congratulations!

Glad to hear you got the bastard off.