is the t-stat installed with the correct part toward the engine ?
I am not certain that one can put one in upside down ..
but one guy I know claims he did.

Does the oil smell like gasoline ?
If it's a waterboxer engine is *really* easy to hang the injectors
outside of the engine and see if they are leaking.
Super easy to do a stray pattern test that way too.

scott
turbovans

On 2/3/2013 12:15 PM, Craig Cowan wrote:
> Well the thermostat was a new, german built unit. Yes, i believe it's
> defective. I plan to install a known good used one soon.
> I tried cardboard infront of the radiator and sure enough, the temp still
> dives at highway speeds. Very odd.
> I will be unplugging the o2 sensor and seeing if that makes it run like
> crap on my next drive of any substance.
> I have put some injector cleaner in the gas, and it has been pointed out to
> me that the starting issue could be a leaking injector, which would also
> account for the decreased fuel mileage. I plan to send a spare set off to
> the wizards for testing/calibrating.
>
> -Craig
>
>
> On Sun, Feb 3, 2013 at 12:13 PM, Dennis Haynes <d23haynes57@hotmail.com>wrote:
>
>> I know it's not Friday but how about doing some real honest to goodness
>> trouble shooting? Seriously! It is easy enough to test the O2 sensor to
>> determine if you are getting proper mixture control. Also, if the engine
>> temperature is falling at highway speed you may be going into open loop
>> control or even worse warm up enrichment. In addition the lower temp also
>> means less efficiency and increased oil viscosity.  Four screws, change the
>> t-stat. Keep in mind that extended warm up time, idling, additional
>> headlight and heater fan use all affect fuel economy. Automatics and
>> Syncros
>> take a real hit for winter operation.
>>
>> Dennis
>>
>> -----Original Message-----
>> From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
>> Craig Cowan
>> Sent: Saturday, February 02, 2013 3:19 PM
>> To: vanagon@GERRY.VANAGON.COM
>> Subject: Re: TERRIBLE GAS MILEAGE/Running Cold?
>>
>> Well, i've gotten a step closer to solving the running issues, i believe.
>> Yesterday i found the temp gauge will still dive above 60mph, and it was
>> warmer (25*F or so?), but i think the issue is bigger than just a
>> faulty/weird thermostat. I think my 8mpg running is in part coming from
>> terrible grounds.
>> When I first built this bus, for whatever reason I seem to have forgot to
>> deal with the grounds?
>> My chronically slow starting condition suddenly made since, and i dove into
>> the engine bay to find the braided cable snapped off in my hand, and all
>> the
>> ring terminals looked like crap.
>> I cleaned up some of the ring terminals and replaced the ends of a few
>> others. I put a 4 gauge grounding cable from the engine to the body and
>> from
>> the starter motor's lower bolt to the body.
>> My starting is still screwed up, but seems improved.
>> I can't wait to see how this effected fuel economy. I imagine the entire
>> fuel injection system was reading poorly if the grounds weren't sound.
>> Hopefully my messing with wires didn't awaken any new beasts.....
>>
>> We shall see.
>>
>> -Craig
>>
>>
>> On Fri, Jan 25, 2013 at 11:52 AM, Stuart MacMillan
>> <stuartmacm@gmail.com>wrote:
>>
>>> I've had a surprising number of aftermarket thermostats not work
>>> properly over the years.  Quality control is non-existent on some of
>> these
>> parts.
>>> Your high speed temp drop points to the T stat not cycling or opening
>>> too far at speed, which is pumping the coolant through the valve at
>> higher
>>> pressure and perhaps holding it fully open.   T stats are constantly
>>> adjusting, or should be, to keep the engine temp constant.
>>>
>>> Change it to what Dennis recommends.
>>>
>>> Stuart
>>> '85 Westy
>>>
>>> -----Original Message-----
>>> From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On
>>> Behalf Of Craig Cowan
>>> Sent: Thursday, January 24, 2013 12:00 PM
>>> To: vanagon@GERRY.VANAGON.COM
>>> Subject: Re: TERRIBLE GAS MILEAGE/Running Cold?
>>>
>>> Hmm.... It is an aftermarket thermostat but stock temp and speced for
>>> the Vanagon. It was stamped Germany and the club installed it, getting
>>> the seal of approval by several members.
>>> It also did operate as expected, and it works fine up to 60mph.
>>> Odd....
>>>
>>> -craig
>>>
>>> On Jan 24, 2013, at 2:18 PM, David Milo <dellaone@GMAIL.COM> wrote:
>>>
>>>>  From a post on 12/12/12 from Dennis Haynes: What are you referring
>>>> to as high temperature? The stock Thermostat rating is 87C, (188F).
>>>> That is plenty and should be used all year. From experience, the
>>>> most consistent acting and best response are the ones from the dealer.
>>>> (???). Of the features of the part the top control disc has a rubber
>>>> gasket to ensure no leak by when it is closed. Next choice would be
>>>> the Wahler, (German). I have had some Mehle that fit but they may be
>>> coming from unknown sources.
>>>> If you do go to a parts store, almost all will sell you the wrong
>>>> stat. The lower disc will be the wrong diameter. If the listing
>>>> includes some Audi or other vehicles it is wrong.
>>>> The confusion comes from the practice that T-stats get listed for
>>>> vehicles based on just a few specifications. Usually the top housing
>>>> diameter is the key. Vlave types, bypasses, bleeds, lengths and
>>>> other
>>> features get lost.
>>>> This is a real problem even in American vehicles, trucks, RV's that
>>>> need stats with more flow and thus use a different design such as
>>>> umbrella instead of disc. The wrong stat may jam partly open and/or
>>>> not open far enough for proper cooling.
>>>>
>>>> Dave Milo
>>>>
>>>> On Thu, Jan 24, 2013 at 2:10 PM, David Milo <dellaone@gmail.com>
>> wrote:
>>>>> Aftermarket thermostat? Could be malfunctioning. I have read many
>>>>> times from Dennis Haynes that most aftermarket thermostats do not
>>>>> fit or operate properly. Extreme conditions could exacerbate that.
>>>>>
>>>>> Dave Milo
>>>>>
>>>>> On Thu, Jan 24, 2013 at 1:23 PM, Jeff Lincoln <magikvw@gmail.com>
>>> wrote:
>>>>>> I am reluctant to reply to this Craig but is it possible, even at
>>>>>> 15deg, that it's just because it's cold?
>>>>>>
>>>>>> Gertie runs the temp gauge dead on center - consistantly, until
>>>>>> this week
>>>>>> -
>>>>>> it's been very cold here this week ranging from about 2deg to 15
>>>>>> or so - the needle is running at about 1/4 - 1/3 and cabin heat is
>>>>>> there but not as it was. Again, I could be talking out my backside
>>>>>> but it sort of made sense to me - thinking about trying the
>>>>>> cardboard trick myself just to see if it helps.
>>>>>>
>>>>>>
>>>>>>
>>>>>> --
>>>>>> Thanks,
>>>>>>
>>>>>> Jeff
>>>>>> '85 GL (Gertie)
>>>>>> '78 Bus (Melissa) Patty's Bus
>>>>>
>>>