Thanks Dennis. Right. Stress cracks. I can now totally see that.
Wouldn't have thought of that before though. At times, I'd wondered if
the engine
was being overworked thus causing higher oil temps.
Maybe I'll "kill two birds":

http://vanistan.com/oil_cooler_kits.html

On 12/22/15, Dennis Haynes <d23haynes57@hotmail.com> wrote:
> It is likely those are stress cracks. Yes these coolers do fail. I would
> replace it. As for the gasket hardening that is a sign that the engine oil
> is overheating. You may want to monitor oil temperature. That engine in its
> original application didn’t run at 4,000 rpm for continuous periods.
> Re-gearing and or additional oil cooling could be benificail.
>
> Dennis
>
>
> -----Original Message-----
> From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
> Neil N
> Sent: Tuesday, December 22, 2015 12:03 AM
> To: vanagon@GERRY.VANAGON.COM
> Subject: Oil Cooler Marks

> This is regarding the oil cooler on a Jetta 2.0 engine in my Vanagon.

-- 
Neil n

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