tankman

Well,after waiting for over a month to learn about my 1987 heads which are in the machine shop,I found out this morning that "electrolysis" has eaten some of the aluminum and that one head will not seal . The machinist says he might be able to weld it . How badly am I screwed?
Thanks in advance for all positive responses.

tankman

leesvet

I lost a head to electrolysis many yrs ago. Back in 1990 a bare head was $1100. Total repair at a shop was close to $2500....that was 1990.

YOU can buy a good head for $200 on FleaBay or from the sellers right HERE. Lots of stock heads for sale and NOT expensive either.
This is not the end of the world...just delays the assembly a couple weeks, that's all. You're good.

It was electrolysis that was causing your issues....
I'll never forget seeing my temp gauge shooting UP and then looking in the mirror sunday afternoon headed back to LA after a weekend in Palm Springs with an exceptionally good looking woman, and seeing that WHITE cloud following me....despite all HER efforts that was one of the worst weekends ever..

Start searching HERE and FleaBay. You will have a lead in minutes...

John A. Marker

Other heads available. Even with a used head that is in good shape it would not cost too much to have ti reconditioned.

I think I would pass on the welding. It can be done with aluminum without too much of a problem by someone that is good at welding aluminum. I would be concerned with the coolant passages that you can't see.

So now you know exactly why the head was leaking. It pays to change the coolant every couple of years.

MrWillys

I'm going to assume the damage is on the deck surface? I'd have no problem welding this. It's done all the time.
You could buy these:
http://www.ebay.com/itm/GM-Performance-Parts-12556463-Chevy-ZZ4-Aluminum-Cylinder-Heads-2-New-In-Box-/331009332142?pt=Motors_Car_Truck_Parts_Accessories&hash=item4d11b193ae&vxp=mtrExact same head with a slightly stiffer spring

SunCr

They take a new style intake gasket with retainers to keep the gaskets in place which (per GM's Service Bulletin) is why your old ones got eaten up.
They were used on the '91 (sans LT4 springs), but finding those intake gaskets can be a challenge (one's with the flow restrictors at the rear), because they were only used on the '91 C4. You can get F Body or current intake gaskets that include the Retainers but don't have the Restrictors. Remove the bypass hose to the Intake if you take this route.

John A. Marker

Those ZZ4 heads would give you some more HP

ch@0s

Time to upgrade..heads cam headers and some better runners.

John A. Marker

It sure is easy spending money that is not yours

ch@0s

I totally forgot it wasn't my money. That was a cheap quote.

In that case LT5 swap with Shinoda kit and Melrose exhaust.

SunCr

I used them - the only difference was the end to a number of intake leaks and hopefully, no more blown/weeping head gaskets. You need a lot more than some LT4 springs and valves to change hp/tq. I don't know what the current cost is; I recall paying about $900 for a new pair from a local Dealer, sans gaskets and everything else you need. By the way, Chevy's Bulletin called for longer bolts on the outer intake holes to accommodate the gasket retainers - they're not available; even though they gave a part#. If you want them, you'll have to find a '91 junker and hope that they're there.

96GS#007

LS9 crate engine or a used transplant from a C6 ZR-1, then mix in some aero updates, new wheels, and a nice big brake kit. Top it all off with coilovers, sway bars, trailing arms, etc

$50k or so ought to cover parts and labor if the OP shops wisely.

tankman

I am thanking everyone who took the time to respond to my post. I did travel to the machine shop to see what "electrolysis" meant. The machinist showed me and suggested that I try to locate another head. He feels that he could weld the head but is not sure that the head would seal properly. My 'vette has over 100k miles on it and I am not in love with it so I'm debating how much money I should spend. I think what got me into trouble was that my '87 saw and heard me talking about a yellow 2004 convertible that I saw on a parking lot,didn't like what it heard,so it blew a gasket .

96GS#007

My previous post aside, in all seriousness if this is a reputable shop, welding is not an issue. If you're nervous about it, ask them to warranty it against leakage and head gasket issues for a 12 months.

tankman

Thank you. I'm not nervous about it because I really have no idea about the pitfalls of welding.I don't want to put a lot of money into this 'vette because I don't think I'm going to be keeping it much longer. I'm leaning towards letting the machinist weld if I can't find a head for a reasonable price.

John A. Marker

A good welder should be able to weld this up. The machine shop will then have to mill the head to make the area that was welded flat. You can weld aluminum heads not cast iron. Well not true...you can weld cast iron, but most don't know how and crack things even more than they were before.

tankman

Thanks John,I hope everything is well with you.

John A. Marker

What they should do is grind out the part that the electrolysis has eaten away so they have a clean material surface to weld. Then they will build up the area with weld. The only real important part is the area of the head that needs to be flat. They will machine that to get a flat surface. I am assuming that the other area that was eaten was the water jacket area. If the weld flows into this area they can just take a die grinder and clean it up or even drill it if they have to. you can build up the aluminum and machine it down to where it has to be.

You just have to have a good experienced welder that can weld aluminum. That is the critical part. You have to heat the head as you weld to get the aluminum to flow and then use an aluminum rod to fill in the area to build it up. Get a in-experienced welder and you will have pits and a mess.

I am doing fine, thank you for asking. I know that you will get thru this fine and get the car back together without major issues. Leaning toward the 2004......nice.

MrWillys

John,
Welding cast isn't that hard if you preheat it. I welded brackets to my diff's preheating with my torch. The NR-211 wire used in my Lincoln SP-135 has enough nickel to do it. I think aluminum is harder. My TPI intake base had to be welded at the waterjacket when I had it apart in 2010. Tech machine in Livermore did a wonderful job.

John A. Marker

I didn't say that cast iron couldn't be welded, just most don't know how to do it so it doesn't crack as it cools back down. Like you did, you have to preheat the iron, weld and then very slowly cool the iron down. Some suggest that after you weld it you heat it with a torch again and pack dry sand around it.

Aluminum is not easy to weld, but with the right equipment and EXPERIENCE it can be done correctly. You can't apply too much heat else it melts and flows away. Too little heat and your filler just ***** up and doesn't bond.

What can I say.....I don't do aluminum...... Lots of steel and some cast iron. I leave the aluminum to those that really have the skill and experience.

tankman

Well,the machine shop called this afternoon and said I can pick up my heads. They have been in the shop for about 6 weeks. A week or so ago, I gave the shop the go ahead to weld the "electroylsis" damage. I will pick up the heads in the morning. Am I supposed to get any type of warranty? I'm also wondering about "the right stuff" for my china walls,etc. I searched and see different packaging. Is there a specific # that I should be purchasing or will any of it do the job for my intake,etc.
I am thanking you in advance.

tankman