Modern Aluminum head question

[JonC]

We all know that back when are cars were new aluminum heads caused problems (taking them off). I have heard chisles were used to bust them off, ouch. With the modern antifreeze and new alloy used on reproduction heads like Offy, Eldabrock, Sharp (what I have) what is the thought of head removal later on, should I stock up on hammers and chisels or have the modern gaskets and coolants solved the problems?

[Tony, NY]

I just removed a set of Edelbrock heads that were on for less than a year. There was noticeable corrosion on the head studs where they went through the head. I have a feeling after several years the heads would have been a big problem to remove. On reassembly, I used anti-seize on the exposed stud. There was also some corrosion in the head openings, but I was only using water with water wetter. Now there is antifreeze and an anti-corrosion additive in it.

[rotorwrench]

A special puller utilizing the spark plug boss threads to pull and bolts against the studs to push. There have been several designs show up on the HAMB. Some use flat heavy plate and some use angle iron or C-chanel. Some of the modern aftermarket speed equipment heads have larger than normal bores to fit over the studs. So large in fact, that it has caused some folks to install locating pins in the decks & coresponding recesses in the heads to locate the things in proper position for torque up.

[rockfla]

No matter the development of new aluminum alloys and modern anti freeze you cannot stop electrolysis/galvanic reaction between dis-similar metals. Then add the anti freeze to the mix and it increases the problem. Tony,NY is on the right track in using Anti Seize compound on the studs and I would use on the face of the nut and the head. If you can find high nickel content anti seize that's even better, it cost more money but better than standard anti seize. You can usually find the high nickel stuff at an industrial supply store for plumbing/underground utility stuff. You could also try MSC or Mc Master Carr if your familiar with them. The problem with anti seize is you cover more of yourself and everything around you than what you need to coat.

[JonC]

I used a aircraft grade of never sieze when I installed the heads so I am hoping that will help, my main question was really with all the new cars out there using aluminum heads and even the hot rods using Al. heads on iron blocks are they having as much of an issue, or has the antifreeze and or new gasket materials making a differance if not should you just plan on pulling the heads every year and fixing stuff.

[rheltzel]

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Having struggled through Chem 1A in college, I'm no chemist, but I think rockfla is correct: electrolysis happens. Rather than trying to delay its effects with various coatings such as anti-seize, which won't change the basic chemistry involved, the better approach seems to me to be to use sacrificial zinc, as is standard in the marine and aeronautical industries.

I have NOS Canadian heads on my new engine. I ordered a zinc probe that goes in one of the temp probe holes on one of the heads. It's been in place about two months so far and I haven't checked it to see if it's working. My plan is to check it after 6 months to see if it's working. The following picture shows it on the right side of the radiator outlet.

I'll report my findings in a few months.

[rheltzel]

Here's the Amazon information on the zinc prob.

[Tony, NY]

Sacrificial zinc works in the coolant. Anti-seize in on the studs in the clearance holes in the heads.

[Binx]

Jon, I would suggest anti-seize on the studs then apply heat-shrink tubing. Use only composite gaskets. Aluminum and copper hate each other galvanically.

Lonnie

[49r]

In July 1975 I put NOS Canadian aluminium heads on my 8BA block. When I took them off 6 months later (dropped a valve seat) one of the head bolts had frozen to the LH head - didn't know anything about the chemical possibilities when I put them on. To get the bolt out I wound the head off. Gave them away 13 years later ...

[Fe26]

Chisels, and in my case axe's.

[JWL]

A local guy brought a set of aluminum Chevy heads to the shop this week. They have been on his iron block engine for 8 years. There is ZERO corrosion, erosion, etc. The engine has always had a 50% anti-freeze mixture.

[rockfla]

I'm no chemist but comparing a modern chevy/Ford engine with aluminum heads maynot be equal in that the more modern engines are "Most" likely used on a daily basis, don't know what or why that has a effect on the issue (maybe getting up to running temperature for long periods of time??? DUNNO) but unfortunately our flatheads sit and don't get driven "Most" times on a daily basis. Maybe someone else could speak to the issue but that's just my thought. I deal with this issue daily in the industrial fastener business here in FLA. but instead of anti freeze more with chemicals, salt water, corrosive gases, etc etc. and dis similar metal/alloy fasteners. As for the cars that sit, Ive seen a few times an electronic device that attaches to the frame and plugs into the wall that counteracts electrolysis in static vehicles and grounds everything to neutral. Maybe that's the best solution.

[JonC]

I like the idea of the zinc anode and think it is something I will use but I agree with JWL so many aftermarket heads for Chevy and SBF are out there I never hear stories about them????

[4ford]

I see something here that says aluminum heads and copper gaskets don't work well?? please advise I have offy heads and copper gaskets do I need to change?

[GOSFAST]

Originally Posted by 4ford

I see something here that says aluminum heads and copper gaskets don't work well?? please advise I have offy heads and copper gaskets do I need to change?

This is not an issue when all is done correctly. Been using this combo for over 40 years now, but read on!

It's very important to maintain a 50/50 mix on the anti freeze AND make certain ALL ground straps are functioning. Both these items are critical to help in controlling electrolysis!

Thanks, Gary in N.Y.

P.S. Many years ago when the Vega's ran the aluminum blocks, there were no sleeves in place from the factory. Sunnen-Tools had done some "heavy" experimenting and found the above items were a major cause of the blocks, cylinder bores specifically, deteriorating over time. When all the above items were correct these casting's were good for over 200,000 miles with little-to-no bore wear! It was a "silicon-impregnated" casting using tin-plated pistons.

[4ford]

so use 50/50 and all should be good

[tubman]

I bought an anti-freeze tester from Amazon that not only shows the freezing point of the anti-freeze, but also the pH of the solution. A friend of mine who is a chemist says with today's technology, even a cheap gauge should be quite accurate. I test all of my cars for both each year.

[36tbird]

I have not pulled a head yet where I installed these so I cannot report on the success of my theory, http://www.stefs.com/bandb/products/...washerstep.htm.

My theory is that if I can keep the stud centered in the hole, away from the walls, then maybe removal will be easier. I used anti-seize and 50-50 mix also. BTW, you need a special bit to drill the heads for installation of the step washers. I drilled both aluminum and cast iron heads.

[4ford]

how about copper head gaskets? with aluminum heads??