Date: Sun, 1 Jul 2012 15:36:37 -0700
Reply-To: Poppie Jagersand <poppie.jagersand@YAHOO.CA>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Poppie Jagersand <poppie.jagersand@YAHOO.CA>
Subject: Re: Questions: 1.9l Turbo Diesel Westy running hot. Weak cooling?
In-Reply-To: <4FF0B4DF.8040308@turbovans.com>
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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
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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