308 Head fused to block

I know I cant be the only guy to have seen this stuff in our lifetimes. I had the same kind of garbage to deal with almost 40 years ago on an old 60's Pontiac V-8. The timing chain/water pump housing was aluminum, held to the block with iron bolts. Though that car was only 8 years old, every single bolt twisted off inside the cover and the cover had to be beaten and pried off the motor to get it off. Crude, but no big deal when parts were a dime a dozen and readily available. Had it been some museum piece with NLA parts, one would have drilled the studs and saved the cover. We assume the same ideals with a Ferrari head, we want to try to preserve the parts.

The primary cause of all this corrosion though, is age and neglect. Same issues today as existed 40 years ago, a 100 years ago, or 1000 years ago. Some of these engines haven't been apart since they left the factory in the 70's and 80's, since Carter or Reagan were President. Its too long. But in addition, many never received regular coolant system flushes and fresh antifreeze. Worse yet, some have only had water in the system (southern states), with no additives added to prevent corrosion.

Some of you also have the misguided idea that gaskets perfectly seal things forever. They do not. They limit leaks, but there is ALWAYS some weeping. Coolant weeps around the head gasket and wicks up the head studs and down into the block around the studs threads. And as it breaks down through heat/cool cycles, it adds an acidic agent to accelerate the corrosion between the iron stud and the aluminum head and bond them together. Regardless of coolant changes, miles, heat/cool cycles, water only etc., TIME is always the major factor. There is a time period where the heads will always just pop right off. But there also comes a point where, in the case of a motor as we are debating here, that that TIME has long passed.

30 years ago (seriously, I'm talking 1979/1980 time period), I recall a conversation discussing these very issues. Supposedly, someone local had been trying to get a cylinder head off a vintage Ferrari V-12, and in the end cracked the head in about 5 or 6 places. That head hadn't been off in 20 or 30 years either. The only really good way to prevent this exercise, is to find some reasonable time interval to disassemble the engine on a regular basis. No one in there right mind would intentionally leave an exotic aircraft engine together that long, one really shouldn't expect a Ferrari to be any different. 10, maybe 15 years maximum. Beyond that and you start looking at the kind of issues being discussed in this thread. Like leaving spark plugs in forever because no one tunes up engines anymore is a prime example. SNAP!

At some point one has to ask themselves how long you want to fight with something like this. The heads worth about $2000 lets say, in good condition. You wont know if its salvageable until its removed, it could already be junk. I personally wouldn't have the patience to wait around a year and half $&($%# with it if that was the only major issue with putting the car back on the road, id saw it off and move on after I ran out of ideas.

Some ideas. Feed some cord down the spark plug holes, enough to stop the engine about 20-30 degrees BTDC, ATDC. You should be able to apply 150 foot pounds to the crank pulley bolt, perhaps swinging the breaker bar back and forth could effect light slamming, "pushing" the head upward. Find some means to apply leverage under the head to as to NOT harm the block, but to force the head upward enough to break its hold. I first would try heating it as Brian suggested though, and get it HOT. You'll probably need to reach 250-300F to really get anywhere. Just don't exceed 300F or you could ruin everything. Have fun!

 

ramosel,

The Permetex antisieze I was suggesting is good to 1300 F (650 C) according to the label. It is Permetex part number 133K. I don't know if it is still available but it is wounderful stuff. Alternative high temperature antisieze compounds are also likely candidates.

For stud od and head bore id purposes it appears to be significant overkill. It's hard for me to conjure up any scenario where the head temperature will exceed even 250 F (121 C). After all, the head is liquid cooled. Even if there is a total loss of coolant, and the 250 F (121 C) limit is exceeded, the engine is likely to sieze well before the antisieze temperature limits are approached.

Calipers are a completely different animial from a temperature point of view. But even here I think the Permetex may be ok. While discs can glow red hot, and I'm not sure at what temperature this occurs, but it is likely in the 1300+ F range, the calipers should be a good bit cooler. The calipers are, after all, insulated somewhat from the discs by the pads and caliper piston. I personally have never seen calipers glow but under racing conditions this may be possible. If this is the case, even the best of brake fluids would be inadaquate as I think the best of the dry boiling points don't exceed maybe 600 F (315 C)?

In short, a high temperature antisieze should be adaquate in controlling the stud-to-head bore corrosion issue.

Bill

 

Robert,

There is a high liklihood that I'll be pulling a 308QV engine shortly. Here are just a few quick step/tips, etc. that might help you in the process.

-Muffler, pipes, etc
-Front header (the one against the bulkhead)->Unbolt from head and allow the rest on chassis
-Rear header->Remove from vehicle
-Air injection tubing, as needed
-Axles at transaxle
-Water tubes, lines, expansion tank
-AC compressor and block studs
-Alternator wiring (Alternator can stay in car
-FI hoses/wiring (I pull the entire FI unit lines, FD as an assembly)
-Wiring for sensors, ignition, etc at multi-pin connectors on LHS inner fender
-Clutch cable
-Shifter linkage (engage 4th or 2nd gear before disconnecting linkage)
-Engine to chassis brace
-Engine mount center bolts only
-And whatever I forgot...

Pulling: I sling the front head and allow the engine to rotate so the differential goes down into the chassis. One the transfer case is "vertical", pull the engine straight up out of the car.

(Special thanks to Paul Newman for his guidance here...as it has been quite a few years since my last 308 engine pull...and "age" may be taking a toll on my memory)

David

 

I used this method 20+ years ago to get "stuck" Alfa Romeo heads off...It worked well, with a large doseage of patience.

David

 

I suggest using thermal insulated ceramic blankets for heating the head/engine. The blankets come in many different sizes and are comprised of interlocking ceramic elements with heating coils passing through them. The end leads plug into a small controller that can be programmed for max temperature, hold time, ramp up and cool down rate. Thermocouples can be placed anywhere you would like to insure uniform heating and reduce thermal gradients that could cause distortion. These units can be rented from companies such as Cooperheat. Have used them for over 25 years for stress relieving weldments on critical aerospace and power generation turbine components.

I also suggest looking at applying PVD coatings to the new steel bolts when the time comes. Either titanium nitride or zirconium nitride would be acceptable coatings for this application. These coatings are hard, very thin (2 microns), unaffected by temperatures up to 1100F and highly corrosion resistant. They would prevent galvanic corrosion between the aluminum and steel stud.

 

Radioman,
You do NOT have to remove the front header if you rotate the engine forward as shown in post #35 of this thread:

http://www.ferrarichat.com/forum/showthread.php?t=28437

It can be done with the plenum on, but is extremely tight when the engine is rotated, I don't reccommend it. You have plenty of clearance with the plenum off. However, you've already got the plenum off if it's the engine I'm thinking of.

IIRC, on some QVs you may have to pull the bell housing first, but that's a lot easier to pull than the front header.

Hmm, It's coming back to me, the rules for pulling QV & 328 engines:
Always pull the plenum to get another 3" of clearance, and avoid it getting in the way of the lifting straps.

If you rotate the engine forward, you have to pull the bell housing but can leave the front header on.

If you rotate the engine backwards, you have to pull the front header, but can leave the bell housing on.

On a recent injected 2V engine pull, we rotated the engine forward and removed it with both the bell housing and front header on. We left the plenum on, but that turned out to be a big mistake as we had essentially zero clearance, and the differential hung up on the rear firewall at one point.

 

If "good enough" is good for you... go right ahead. I was just offering you cheap ($15) alternative to "off the shelf", corner car store silver anti-seize. And no, the silver stuff does NOT work on high performance calipers... neither does the copper stuff... First hand experience. Thats why the pros use/sell ceramic.
Keep in mind the nominal temps you see on a head (oil, water, laser probe) do not represent specific point tempretures in the head especially near the exhaust ports. If you want to be sure your heads come off NEXT time... use a ceramic anti-seize.

BTW - That 1300 degree rating on the silver is a maximum for a short period of time in very specific conditions, not a sustained operation temp. Ceramic has a sustained operational temp of 2000 degrees and a max of 2500... its food safe, non-carbonizing (very helpful in mixed metal situations -think carefully about that statement) and environmentally safe...
Brake fluids - We only run Castrol SRF, and even it breaks down.


Rick

 

Robert,

Since you have the "front" of the motor all cleared off, you can pull the motor out without removing the twill shaft cover and bell housing. They do offer a bit of protection while you have the motor swinging on the hoist. Of course, having the motor out I'd certainly pull them off to check if not replace the clutch.

Rick

 

just wrap around the front bak will rotate it to the right direction. leave the bellhouse on no need to remove.

just pulled mine two week ago
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ramosel,

I don't have a problem using an antisieze with exceptional heat tolerance for the stud to head interface. It does no harm. I'm almost out of the Permetex anyway and might buy a container of the antizieze you recommend as an all purpose selection.

The Castrol product you recommend for brake fluid has a dry boiling point of 590 F. This is 710 F lower than the antisieze temperature limit I suggested. There appears to be significant margin for the retaining bolt application. The 1300 F antisieze limit would seem to be adaquate for your caliper retention requirements but only you know for sure.

Still, to control galvanic corroison on the stud to head interface, temperatures are likely to be a good bit cooler. Even the face of the exhaust ports are likely to be a good deal cooler than 1300 F, but only field measurements or a detailed finite element/finite difference(FEA/FDA) analysis could bound this temperature with a good degree of confidence. For the head to stud application, an antisieze temperature temperature limit of say 500 F should be more than adaquate. The aluminum alloy head material conductivity, while not as good as copper or diamond (best there is), is still pretty good. This means that head temperature gradients across the head volume will be relatively small. Convection heat transfer from the exhaust gas to the exhaust ports will be about an order of magnitude less than heat transfer to the liquid coolant. This means the liquid coolant temperature dominates. This is a good thing. Temperatures at the head bolt locations will be modest. The real issue will be controlling galvanic corrosion and probably all off the shelf anti sieze compounds will do a stellar job, certainly better than nothing at all.

Bill

 

Your last bit says it all... its better than nothing at all.

What we have found (as I'm sure many others have) with the race cars (Trans AM/GT-1) is that things that should be adequate - aren't. As you point out, the SRF should be fine to almost 600 Degrees. We run a radial mount, 6 piston progressive, mono block, alcon caliper with titanium perforated heat vent caps on the pistons running inch thick brake pads - hell, that should isolate the heat well away from the attachment hardware and brake fluid. The $80/pint brake fluid still breaks down. One would think (we did) that a 1300 degree anti-sieze should work. It didn't. Real world - Throw in repeated heat cycles, pounding, vibration, harmonics, mixed metal intfaces, galling forces, humidity, environmental dirt, tire clag (probably a handful more factors I'm missing) and suddenly the silver antiseize doesn't work. Same applies in lesser extremes on things like single nut pin drives, head bolts, header bolts, etc.
So all I was trying to say is - on our beloved Ferraris, which don't have regular head removals - which don't have modern head gaskets - which are prone to weeping - go for the good stuff and assure a long life. Hell, we are all spending way too much money on these things... spend a little more and go top shelf on your anti-seize. I only brought it up because most folks don't know ceramic anti-seize even exists. 20 years from now the next guy to pull your heads will raise a beer to your foresight! Or at the very least not cuss your name...

Rick

 

Nice job,


the part broken is cheap.
BOSCH part # 396334
$ 65.00

Edwardo

 

The method of head removal (cams out) that never fails for me:

Add string to a end cylinder, enough so piston cannot go past TDC. I like to keep piston in the range of 60 degrees BDTC, seems to work better. Use the front crank nut to apply pressure to the under side of head, switching string from one end cylinder to the other so you have a rocking effect.
If head is stubborn, use an INDUCTIVE heat gun to apply a good amount of heat to each stud that the oil will not penetrate. I use 5 heat cycles, letting stud cool a bit between cycles. Now I never let stud turn red, but if you plan to renew them fire away.
NEVER!!! pry, strike or torch a cylinder head - pandora's box waits.
RD

 

Best of luck but I would think twice about drilling the head and consider a light coating of anti-seize on the studs. Also when you reassemble I highly recommend cometic mls gaskets as they are far superior than the stock gaskets.

 

I know this is an old post but I am in the process of trying to remove QV heads on an 85 Euro engine. I have sprayed and soaked with PB blaster and hit with a dead blow and 2x4s with no success. I am going to follow Rifledriver's recommendations and just bought a 1.5" thick block of aluminum. I do not have oxy acetylene, so can I heat the heads with a propane or mapp gas torch? I have a digital thermometer to monitor the temperature. Thank you

 

Be extremely care trying that. Note that a propane torch can melt aluminum, and aluminum doesn't glow red as it heats (in the way that steel does.) It simply turns from a solid to liquid to moment you hit the melting point. The head is so large that the heatsinking effect is going to be of both a benefit and a deterrent to the overall goal. I'd advise finding a scrap piece of aluminum first, and practicing the technique a few times.

 

I have seen QV heads removed by putting small (tiny) hydraulic cylinders/rams under the casting and on top of the studs. This allows controlled pressure to raise the head as evenly as possible across the bank. No heat, no hammering.

This is an example of what was used, but not quite as expensive as these.

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Thank you - so if not a propane torch, what is a good way to heat the heads to 300 degrees as recommended by Rifledriver?

 

I tried the heat gun on the engine stand this weekend to no avail...

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Considering how well aluminum bleeds off heat, it would seem the block will eventually and rather quickly get to the same temperature as the head. So I suspect the best solution is an oven large enough to accept a block with heads.