[Vwdiesel] Injector boss cracks

[Libbybapa at wmconnect.com]

Well, I did manage to change the nozzles in another four injectors from a 
spare engine I have.  All four with nozzles had good spray patterns, and 
identical breaking pressures of 2050, the high spec for the n/a.  I decided to use 
them in my '86 n/a jetta.  The engine has 297,000 miles on it.  I have put 60,000 
of those on it.  I never touched the injectors previously.  I also knew the 
previous owner fairly well, and am sure that he never would have.  I'm sure 
that those injectors hadn't been removed in more than ten years.  Well they were 
so severely corroded in place that I ended cracking THREE of the injector 
bosses.  One is cracked in two places.  I have removed injectors from other 
engines and had no trouble at all.  In the future, I will soak the injectors a 
couple times a day, for several days, with liquid wrench prior to attempting the 
first time removal.  I will always anti-sieze also.  It was pretty clear that 
two of the heat shields did not seal from injector to head.  There was a massive 
accumulation of charcoal/rust filling the whole area around the end of the 
injectors.    When I tested the injectors they all failed miserably.  Breaking 
pressures were all below 1600 psi.  They all dripped,  Two of them just leaked 
streams down to 0 psi.  None of them would chatter.  And all had horrendous 
spray patterns.  Mainly streams.  Amazingly, the only real sign of a problem was 
difficulty starting cold.  The timing seemed somewhat too advanced also.  A 
small bit of smoke.  I was still pulling off low 40's in town and high 40's, 
and occaisional 50+mpg highway.  Judging from the injectors, I can't believe it 
even ran.
The Question:  Is the head a large paperweight or future soda cans?  Any 
potential fixes.  I will be talking to a machinist friend to see what the cost of 
repair would be, but I have a feeling a used head would be cheaper than the 
welding a re-machining of the bosses.  Makes me kinda bummed.  
The Other Question:  Any other recommends for freeing stuck injectors?  I 
have a feeling that it is unlikely that any method would have freed these without 
damaging the head due to the extreme corrosion of the threads (head and 
injector).  But, if possible I would like to avoid a similar situation in the 
future.
Andrew