Date: Mon, 26 Apr 2010 14:03:31 -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: cooling system diagnostic help? Long,
lots of info about whats been done so far.
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re
Is there a way to check the integrity of a head/head gasket when the leak
is not letting coolant into the cylinders? Or do I pull the head? Takes
about 4 hrs, but could there be a flaw/fault that I wouldn't see by eye?
Ugg, was not planning on this deal..
Three main choices there...
compression test might reveal something ... I have seen for example....I'm
checking compression on # 2 ...and I see bubbles heading toward the pressure
bottle ....which means exhaust is or can get into the coolings system
.............pull head.
next...leak down test - same thing. And a little better test.
next ...sniff the coolant for hydrocarbons,
or use one of theose 'block testing' dye kits.
The test fluid turns yellow ( or brown, forget which just now ) in the
testing device if there is HC in the coolant.
if ever you get mysterious or intermittant overheating/can't sustain
running...
and it's not the normal stuff, or internal or external leaks..
you think about exhaust getting into the coolant at the head/head gasket.
if you ever get 'too hot engine' and cold radiator ...like the main pipes
were blocked, but they are not, and it's not the other common issues at play
....it's exhaust gases getting into the coolant.
if it just 'unbleeds itself' ....like every 40 minutes of running you have
to bleed ....same thing.
oh....Extensive and Excessive bleeding should never be neccessary. You can
change entire engines, and just keep topping up the coolant every
warm-up-cool-down cylcle for a few days ....and it'll be fine.
If you bleeding and bleeding ...see 'exh gases getting into the coolant.'
what year van or radiator is it ?
The 83 and later radiators remove heat mo' betta than the all metal 82 one.
Scott
www.turbovans.com
Scott
www.turbovans.com
----- Original Message -----
From: "Don Hanson" <dhanson928@GMAIL.COM>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Sunday, April 25, 2010 8:14 PM
Subject: Re: cooling system diagnostic help? Long, lots of info about whats
been done so far.
> If it is a head problem it is not showing in the cylinders.
> I didn't include that when I did this preliminary diagnostic this evening
> I
> did not totally re fill and re-bleed the cooling system. The pressure
> tank
> was empty after my boil-over incident. I simply poured in enough water to
> fill it and then started up the motor...so the bubbles coming into the
> pressure tank may (fingers crossed) have been some air coming from the
> hoses
> and empty cooling passages....But the over-full episode kinda makes maybe
> wishfull thinking.
>
> Might be time to go get that $300 used motor I've been looking at....It
> IS
> a vw...every vw should have a spare motor, right?
>
> This van came to me with a full-time blinking coolant light and I
> couldn't
> get it to stop...The previous owner said he also had tried but gave up and
> just let that sucker blink all the time. I put some tape over it and
> having
> been driving without a problem for over two years and about 40k
> miles...watching the temp gauge and checking the coolant level every oil
> check...which means every fill up of gas...I always check my oil...left
> over
> from my air cooled days, I guess.
>
> Is there a way to check the integrity of a head/head gasket when the leak
> is not letting coolant into the cylinders? Or do I pull the head? Takes
> about 4 hrs, but could there be a flaw/fault that I wouldn't see by eye?
> Ugg, was not planning on this deal..
> Don Hanson
>
>
>
> On Sun, Apr 25, 2010 at 7:36 PM, mark drillock <mdrillock@cox.net> wrote:
>
>> Sounds like a blown head gasket or cracked head, either letting
>> combustion
>> gases into the cooling system. The combustion gases are 1000s of psi so
>> it
>> takes only a tiny and brief breech for a small gas bubble to get through
>> and
>> then expand in the much lower pressure cooling system. The fact that
>> coolant
>> doesn't yet leak the other way doesn't matter to this possible diagnosis
>> as
>> that takes a larger problem.
>>
>> When you say your temp led doesn't work do you mean it doesn't blink a
>> few
>> times every time you turn on the key?
>>
>> Mark
>>
>>
>> Don Hanson wrote:
>>
>>> Hi all, recently I've noticed my cooling system is being weird.
>>> Don Hanson
>>>
>>>