Help, heads went bad

[spokrose]

I have a 03 6.6, 65,000 miles, injector never replaced, started building pressure in cooling system, could smell coolant in exhaust. GM dealer, removed heads, found metal gone around injector area, both heads need replaced. I have a aftermarket warrentee, they will not cover cost [7000.$$], they say it is due to performance chip that i do not have, i will have to take them to court, can anyone help, i need info on why the heads would do that. Thanks david.

[More Power]

Dex-Cool has proven to be an excellent coolant, and has been used since 1996 in the GM diesels.

I did a story on Dex a few years ago, and found while doing the research that Dex can allow/produce corrosion when there is an air/Dex interface - like when there is a long-duration air pocket in the cooling system. If the internal surfaces of the cooling system is fully wetted, there is no problem.

So, the aluminum corrosion problem some have seen where the stainless-steel injector cup passes through the aluminum cylinder head is (my theory anyway) due to combustion gases more or less continuously passing through this area over a long period of time. Some amount of the corrosion could be due to the Dex and some could be due to gas-cutting of the high temp combustion gases.

Yes, power mods can contribute to this problem, I suppose, but the most likely cause of an injector cup seal leak is because of inadequate (or no)cup prep during an injector replacement.

Jim

[Kennedy]

I would really like to see the heads or at least pics of the erosion.

[Mark Rinker]

I take it that the factory warranty has run out? What was the in-service date?

[spokrose]

I am picking up the truck in a couple of days, i will post pics of heads, the dealer that did repairs said has never seen heads erode like this, thinks possible faulty castings? dealer said engine warrentee for 03 was 5 year 100,000, truck was serviced every 7500.

[Kennedy]

Look at the old heads and see if the steel "buttons" are in place where the injector ends ride on the casting. If they are there, I would make sure the dealer tech installed new ones.

I had a friend who had heads under warranty only to later pop an injector cup. The Tech did not put the buttons in so the hold downs were riding on bare aluminum...

[More Power]

Who's got the best deal on new/used cylinder heads?

Jim

[madmatt]

I've got a set of LLY heads.

[spokrose]

here are some pictures

[Inspector]

Pics didn't show.

[spokrose]

I tried to post pics with no luck, any suggestions?