Date: Sun, 1 Jul 2012 21:09:56 -0700
Reply-To: Scott Daniel - Turbovans <scottdaniel@TURBOVANS.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Scott Daniel - Turbovans <scottdaniel@TURBOVANS.COM>
Subject: Re: Questions: 1.9l Turbo Diesel Westy running hot. Weak cooling?
In-Reply-To: <1341182197.84847.YahooMailNeo@web45304.mail.sp1.yahoo.com>
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Hi Martin,
I would say that if your radiator is original and 30 years old, it's
very, very due.
not recovering fairly quickly from getting hotter than normal is another
sign I'd say, that the radiator is only doing say 60 % of what it once
did, in terms of heat removal.
If the temp gauge is working right ....I consider dead in the middle to
be very close to 180F.
If everything is pretty right, an 80C 'stat will make it run just to the
left side of the LED,
an 87 C stat will make it run to the right side of the LED ,what I might
call 55 % on the gauge.
Many manufactures just put 'normal' or 'hotter' , or 'over here is on
the cool side' rather than temp numbers in degrees.
Likely to allow for variation from gauge to gauge, van to van etc. Rare
is the factory temp vague calibrated in #'s ...and if they do they still
often make it a little vague sometimes.
My 1970 Mercedes has 100 on the bottom, 170 in the middle, and 250F
at the top. They don't want people nagging or freaking out that it's
reading 185 when it should read 180 or whatever. They are imprecise
intentionally I suspect.
What is important is that you know what is normal on the gauge for your
van ...
and you recognize when it's cooler or hotter than what has been normal
for you over time.
( as you may know, a very sudden big coolant lost in the engine may not
be shown by the temp gauge- as it only reads the temp of a liquid, and
not steam. . Engines have been seriously harmed that way ...very sudden
big coolant loss, never shows on the temp gauge. Might be why VW put a
level sensor on all 83's and up. They planned for it too, as the wires
for it are in your 82 van - US models anyway , but no level sensor in
the coolant pressure bottle. They got to that in 83.
I see all the time where they did many improvements, but they didn't
finish improvements until the next year. I think that is so VW could
say '21 improvements on this new model.' They do it chronically. Many
years of vanagons 'have features that are finished' in the next year
model. You see if over and over in vanagons as the year models
progress. )
the 'common failure mode' of t-stats is 'allow the engine to run too
cool' .
They can fail the other way too, but usually it's that they open soon,
and don't keep things fully up to temp.
the volcano shaped water pump impeller is the right one to have, whether
in plastic or cast iron.
Also, inspect the water pump housing impeller face. - those get
corroded and worn eventually also, if badly worn could affect how well
the water pump moves coolant.
I don't see how the paddle wheel stamped sheet metal impeller can
work very well, myself.
I'd say 'radiator'. And it's a little bit of a project, but 'the cool'
82 diesel vanagon radiator upgrade is the common aluminum/plastic tank
83 and later vanagon radiator.
You need, to go with that, the fan shroud for that type radiator, the
lower radiator brackets from an 83 or later vanagon ...
need to rewire the fan sender set up, and need two lower front hoses
from an 83 to 84 waterboxer vanagon.
83 diesel front hoses should work too. The early 'metal pipe'
waterboxer hoses are easier to find ...fits all 83 to half way through
85 waterboxer ..as long as they have metal pipes, and not the larger
plastic ones.
I'm sure there are write-ups online or on this group for this
later-type radiator conversion / upgrade.
It's worth it in the long run.
Scott
www.turbovans.com
On 7/1/2012 3:36 PM, Poppie Jagersand wrote:
> Yes, still has the '82 OEM radiator. Worked fine through 30 years
> through 3 engines 190,000 miles, but maybe it is part of the problem
> now. There was some sludge in the coolant when I did the last flush
> and fill just before this trip. Never had that before.
>
> Temp readings were taken with an IR thermometer while van was still.
>
> In your set of tests below it passes all except 4. It does nor come
> down in temp quickly after a period of high load.
>
> I don't know what temp it reaches under load while driving since
> (unhelpfully) VW didn't put any numbers on the temp gauge. Needle used
> to go just beyond the LED, and I had very little variation with engine
> load. Now I have much more variation 1/8 to 1/4 of full scale reading
> as meintioned.
>
> Yesterday it also developed a slow drip from the water pump, so that
> has to be replaced for sure. Just waiting for the ground to dry up
> somewhat after the rain this morning.
>
> I guess what maybe didn't come through in my original email was:
> 1. Do thermostats fail so to not open correctly (the failures I've
> seen is that they don't close fully so engine runs too cold)
> 2. Have anyone have the cast steel impeller type water pump fail so
> that it doesn't pump the coolant efficiently? (I know the stamped
> steel impeller ones sometimes did, but never had a problem with this type)
>
> Martin
>
> ------------------------------------------------------------------------
> *From:* Scott Daniel - Turbovans <scottdaniel@turbovans.com>
> *To:* Poppie Jagersand <poppie.jagersand@YAHOO.CA>
> *Cc:* vanagon@GERRY.VANAGON.COM
> *Sent:* Sunday, July 1, 2012 2:36:47 PM
> *Subject:* Re: Questions: 1.9l Turbo Diesel Westy running hot. Weak
> cooling?
>
> Hi.
> Do you have the all metal 82 diesel vanagon radiator ( used only that
> one year )
> or do you have the later style aluminum one with plastic tanks on it,
> used in 83 and up vanagons ????
>
> < why do people fail to describe exactly what version of a diesel
> vanagon they have ?? -that would be so helpful. >
>
> Cooling systems are pressurized to raise the boiling point of the coolant.
> Water boils as you know at 100C at sea level.
> by allwing it to be pressurized up to 15psi the boiling point is
> whatever......at 15 degrees F above boiling point.
>
> What is your actual symptom ?
> what is not actually working right ?
> the temp readings you give sound good.
>
> if it does the following it's working right -
> 1. It sustains running without boiling over or getting excessively hot.
> Say you have a 180F t-stat in it. Under load on hills on a hot day
> it may get to say .....200 F ....that's normal. If it gets to that
> temp on a long hot hill and goes back down to 180F on the level...all
> is fine.
> If it gets to say 220F then you might start thinking about if you
> radiator is removing heat well enough.
> The metal 82 DV radiators are known for not removing heat that well.
> < one of several things used only in that 'one year' ..the 82 DV,
> which is the first ever water-cooled vanagon ...there are things they
> didn't get that right on that model, or that they improved on all 83
> and up vanagons after the 82 model >
>
> I have had my own personal TD vanagon work fine with a brand new all
> metal 82 DV rad for about 5 years, then distinctly run much hotter on
> long hot hills, even to the point of not being able to crest a 7 mile
> long grade successfully, where when I first put that rad in, it did
> that same hill just fine, same van, same engine, everything.
> Converting to the 83 and later type radiator fixed that just fine.
>
> I have seen radiators that appear to work ..yet ......
> here's one case. New head gaskets and everything on an 86 GL. New
> t-stat, new coolant, many new plastic parts etc. It would 'pulsate'
> in the engine hoses after shut down from being fully warmed up. We
> found numerous small not right things in the engine area, but nothing
> changed until we took out the radiator. We found junk in it
> ....flushed it out backwards with hot water extensively, put it back
> in ..that fixed it. We then installed a new radiator and all was fine.
>
> 2. heater/s work well.
> 3. it gets up to temp fairly quickly.
> 4 it comes back down to regulated t-stat temp after going up a big hot
> hill.
> 5 no gurgling or anything like that.
> 6. no coolant disappears. .
> 7. no air seems ever seems to get in. If it does that you start
> thinking about exhaust gases getting into the coolant at the head or
> head gasket, which is not that uncommon.
>
> on the coolant itself ..
> a weaker solution than 50/50 a-frz/water cools better than 50-50. Read
> what it says on the side of a Water Wetter bottle.
> Run water-wetter or similar product in the summer.
> Run a good newish german made thermostat ..if choices are 80C or 87 C
> ..I like the 80 in the summer, the 87 in winter.
> What exact type or brand of anti-frz does not matter very much in my
> experience.
> - just a quality product applied correctly.
> - and not left in there forever. Personally, I have been adding
> just a tiny bit of water soluble machinist's cutting oil as a water
> pump lubricant and rust inhibitor to hundreds of cars going on two
> decades now with just excellent results.
> Perhaps a small cup's worth in the entire system. I just do not get
> corrosion in my cooling systems..
> and I see just horribly corroded diesel vanagon cooling system parts ..
> rotted off aluminum hose necks and so forth. Just atrocious. No
> reason for it really ...just pure neglect at work there.
>
> Hope this helps,
> scott
> www.turbovans.com <http://www.turbovans.com/>
>
>
>
>
> On 7/1/2012 11:26 AM, Poppie Jagersand wrote:
>> In the previous post I described how we had to interrupt our BC vacation and turn back on the first day because the 1.9l Turbo Diesel was running hot.
>>
>> Before the trip I had prepared the cooling system by a flush with Prestone super cleaner, which is based on sodium citrate, and fill with the modern pink coolant (Havoline 5year 100,000 miles Dexcool compatible -- I've been using this before).
>>
>> I also tightened the water pump belt with 1 shim as it was slipping on start up. The belt ended up a bit tighter than I prefer, but there's really no option less than one shim with this tighten system. Belt is a newer Contitech that seems stiffer and more slippery than typical belts.
>>
>> The water pump is VW Brazil made with cast iron impeller. Have used this one before with good results. I found it much better than the after market pumps with flimsy stamped steel impellers.
>>
>> I'm not so surprised if the belt tightening caused the bearing and seal on the water pump to fail.
>>
>> What I wonder is if and why cooling efficiency depends on the system being pressurized? Since I had no air inside I was puzzled about the temp increase and wondering if something else may also be amiss. I also saw no signs of boiling over (which I thought would have made the coolant overflow from the reservoir and splatter in the back of the engine compartment). So if coolant was properly circulating I was thinking it would cool even if under atmospheric pressure instead of the usual 15psi over pressure kept by the pressure cap.
>>
>> I'll also change the thermostat for good measure.
>>
>> My past experience with thermostats is that they usually fail by warping so they don't close tightly, and the engine takes longer to warm up, or runs too cold in the winter.
>>
>> Have anyone had a thermostats fail to open properly, and cause hot running? Thermostat not open fully would prevent full coolant circulation to the radiator, and perhaps worse, may not fully close the coolant bypass loop, so coolant just recirculates in the engine instead of going through the radiator. Anyone experienced this?
>>
>> The thermostat does appear to open at about the right temp. When starting cold and driving temp rises quickly to temp gauge middle, then much more more slowly.
>> On idle tests rad remains cool until temp gauge reaches middle, then heats up when temp gauge needle passes middle LED.
>>
>> I'm not sure how to test a radiator. Running the engine at 1500rpm high idle fan stage 1 comes on at about 90C temp and stays on low. Using an IR thermometer to measure the temp of the coolant I get:
>> Coolant to radiator: 90-92C
>> Coolant from radiator: 75-80C
>> Outside temp 20-25C
>> So radiator reduced coolant temp with 10-15C
>> Normal?
>>
>> Any other thoughts on what might have gone wrong?
>> And what else should I test?
>>
>> We're about to leave for a 3-4000km trip in rural BC so I don;t want more surprises further down the road...
>>
>> Thanks,
>> Martin (and Diesel Westy 1.9l TD "Poppie")
>>
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