Aluminum Cylinder Head Crack Detection Audi A4 2.0 Turbo

Using the Goodson dye system to identify a crack below the valve seat in the Audi 2.0. Since aluminum isn’t magnetic other methods have to be used for crack detection.

[@mikemurphy7519]

You are supposed to wipe off the die prior to applying the developer

[@checkmatenate]

Yeah you’re supposed to wipe it off bro

[@AndyZ325is]

Had an Audi Avant A4 with the 20V 1.8T. Sludged up badly. Had the BG treatment done which seemed to work. That was at 65,000 miles. At 85K and multiple coil packs later, the head cracked just like this one. AUDI stands for Another Underhood Disaster Incubating. Sweet driving car with a sour lemon engine.

[@skylinefever]

Many ended up like this because they said 10,000 mile oil changes were acceptable. They also used about 3.7 quarts of oil. An oversized filter was called for, but having 3.9 quarts of oil wasn't going to fix such gross miscalculations.
Extreme oil change lengths, and the weakness of Castrol Syntec 5w40 was the death of many B5/B5.5 Passats and related Audis.

[@skylinefever]

I figured it was a 1.8L, many of those 20V heads were on 1.8L engines.

[@TurbidFish]

Will cylinder head go to the junkyard or wil it be repaired?

[@skylinefever]

Given how common the VW/Audi 20V is, usually this will go in the recycle bin and a crack-free core will be used for rebuilding. Welding is usually reserved for situations where good cores are rare, super expensive, or hard to find.

[@LakelandAutoMarine]

It was scrapped. Much cheaper to start with a good core than repair this one.