Date: Fri, 17 May 2019 19:37:52 -0700
Reply-To: alex@MEVAY.ORG
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Alex MeVay <alex@MEVAY.ORG>
Subject: Coolant Loss/Hose clamp tips?
Content-Type: text/plain; charset="UTF-8"
Hi All,
I'm a little embarassed to be asking this question, but Friday on the
list here is supposed to be a little more lighthearted, right?
TLDR, can anyone share any tips on getting hose clamps to work
reliably over the long term?
My van has been drinking some coolant, maybe a pint every few thousand
miles. This has been low on my list, as there haven't been any other
concerning symptoms (i.e., head gasket leak). Occasionally I would
find a few drips on the ground, trace it to a hose clamp, and snug it
up. Other than that, the amount of loss seems so small that it
evaporates before it leaves any evidence, making troubleshooting
difficult.
I recently got a loan-a-tool pressure tester from Autozone,
pressurized the system to ~15psi, left it there for most of a day,
pumping up as needed, hoping that with things cold, the drips would
remain visible. I discovered little seeps/drips from NINE places.
I am for sure a little gun-shy on tightening hose clamps, as I've been
burned by low-quality aftermarket replacement plastic flanges for my
I-4 that mush into oblivion under the tension and begin leaking. I've
gradually been replacing these (and any barb couplers) with metal
where possible, and swapping any notched hose clamps with the smooth
kind.
I tighten these "firmly" with a screwdriver-sized implement. Last
time around, I marked the clamps so I could see if they backed off,
but don't have any data there yet.
I'm considering installing one of those stainless coolant tube
replacement sets, but as I understand it, this adds a hose-clamp
junction above the gas tank, where a drip will be a big pain to fix,
so I want to make sure I figure this out first.
So...
Is there a torque recommendation for these clamps? Is it different
for plastic or metal flanges?
Do these leak due to insufficient initial torque, loosening over time,
or plastic creep (in the hose or plastic flange)?
Do the "pinch" style ones work any better?
For high-risk locations (above the gas tank), what about some of those
clamps with integrated spring to help maintain tension?
Thoughts appreciated,
Alex
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