Sorry mick disregard my last email, I should have read this one first!!
> Terry and Zac
> Thanks for ur responses. It really is an interesting problem.. And quite
> unusual i think... normally we are always looking at OVER heating not UNDER
> heating!
> The new thermostat was tested thoroughly and opens and closes as per spec.
> The heater is installed but not connected.
> The bypass/heater hoses are just joined together ie a hose runs from the
> heater outlet near the water pump back to the heater fitting on the back of
> the engine.. Any problems with this set up?
> There is no bypass under the thermostat.
> I have an expansion tank set up on the radiator if this might make a
> difference.
> I didn't get the chance to test whether blocking off part of the radiator
> helps the problem but I am about to do so today. I will block about a third
> of the radiator and see what happens.
> Cheers
> Mick
>
>
>
>
>
>
> ----- Original Message -----
> From: "Terry Rudd" <[EMAIL PROTECTED]>
> To: <[EMAIL PROTECTED]>
> Sent: Friday, February 01, 2002 1:32 AM
> Subject: RE: Radiators/UNDERheating// 2
>
>
> > Zac,
> > You're right, it's definitely much safer to undo the cap cold and let it
> > warm up that way.
> >
> > Haven't some L20B's got a bypass hose coming out from underneath the
> > thermostat housing. This could be the problem if Mick has one and it's
> > connected to the water pump. I seem to recall seeing this sort of bypass
> on
> > my mum's Bluey, I know it was quite different to the L16/L18 bypass.
> >
> > I would say that anything under 170F is too cool. The stock 1600 (70+)
> gauge
> > has a fairly narrow band, the first line is ~165F, the first vertical line
> > which is the start of the normal range is 170F, the mid line left of the E
> > is 180F, just left of the P is 190F and the start of the red is ~205F
> which
> > is a guestimate as I did the test with a 192F thermostat so it never got
> up
> > to the red. It roughly indicates around ~10F for every 1/4" so to answer
> > your question IMHO the T is ~175F so it's not too cold.
> >
> > regards
> > Terry
> >
> > -----Original Message-----
> > From: [EMAIL PROTECTED]
> > [mailto:[EMAIL PROTECTED]]On Behalf Of Zac Campbell
> > Sent: Thursday, 31 January 2002 11:54 PM
> > To: [EMAIL PROTECTED]
> > Subject: Re: Radiators/UNDERheating// 2
> >
> >
> > I will agree with Terry about his locations of the Celsius markings on the
> > stock gauge.
> > Terry when you suggested he take the cap off while the engine is running,
> > maybe he should do it when the engine is stone cold, then start the
> engine -
> > wait until it gets up to temperature and when the thermostat opens you
> will
> > see the coolant start flowing into the radiator. If it is flowing from the
> > start then the thermostat could be stuck open a tad (or of course he could
> > have a hose of sometype bypassing the thermostat).
> >
> > But Terry, going back to your earlier comment about an engine running too
> > cool, is it possible to put a point on what too cool is? With the thermo
> > fans and switch I have my engine very rarely gets above 85C and if
> cruising
> > on no load it gets down to the start of the T sometimes.. too cold?
> >
> > cheers,
> > zac
> >
> >
> > ----- Original Message -----
> > From: Terry Rudd <[EMAIL PROTECTED]>
> > To: <[EMAIL PROTECTED]>
> > Sent: Thursday, January 31, 2002 10:54 PM
> > Subject: RE: Radiators/UNDERheating// 2
> >
> >
> > > Mick,
> > >
> > > Working out how your engine is running cool whilst on the move gets a
> bit
> > > tricky now. Logically to me you have to have either water circulating
> > > through the radiator with the thermostat shut somehow - the heat has to
> be
> > > exchanged into the atmosphere somehow especially as it warms up when
> > you're
> > > stopped i.e. no airflow.
> > >
> > > Have you got a heater fitted?
> > > How are the bypass hoses connected or are they blocked off which is the
> > > normal thing with weber manifolds?
> > >
> > > It doesn't make a lot of sense to me and I'm not too sure what we do
> from
> > > this point, as you know my rad is very similar to yours and i've never
> > > experienced anything like this except when a thermostat has jammed open.
> > I'd
> > > carefully crack the cap when the engine is running and have a look see
> > > what's going on inside the radiator, it's very evident if water is
> > > circulating when the thermostat should be shut. For info 88 degrees on a
> > > stock gauge is towards the end of the M start of the P region, stock 82
> > > degrees is just to the left of the E. What about pressure?
> > none/some/normal?
> > >
> > > This post is a bit like yours too, more questions than answers - the way
> > it
> > > goes when trouble shooting I spose.
> > >
> > > regards
> > > Terry
> > >
> > > -----Original Message-----
> > > From: [EMAIL PROTECTED]
> > > [mailto:[EMAIL PROTECTED]]On Behalf Of mick ralph
> > > Sent: Wednesday, 30 January 2002 11:21 PM
> > > To: [EMAIL PROTECTED]
> > > Subject: Re: Radiators/UNDERheating// 2
> > >
> > >
> > > Hi Terry
> > > Good to hear you had a decent break over xmas.. And glad to see you back
> > and
> > > active here..hehe I have some more information about this thread.. I
> > checked
> > > the thermostat today and sure enough it isn't fully closing. I had
> another
> > > one here the same so i tested it and it was fine so I chucked it in. I
> > also
> > > set the Webers up a bit better,,, Then go for a run on the motorway and
> > sure
> > > enough the temp DIDN"T go up..just stayed on the stop ie 0 ... Come off
> > the
> > > motorway and sit at traffic lights and straight away the temp starts to
> go
> > > up and sits steady at "E",, As soon as i go back on the motorway the
> temp
> > > drops down to zero again. So I get off the motorway and by the time I'm
> in
> > > my driveway the gauge is up to "E" again..
> > > So
> > > 1. The thermostat is tested and works @ 88 degrees.
> > > 2. The gauge seems to be ok
> > > 3 The engine feels a bit different ie down on power and unhappy
> > > 4. The engine is hot to the touch after such thrashing but the radiator
> is
> > > just warm
> > > I can see how a thermostat would cop a hiding in these circs and the one
> i
> > > tossed is less than 12mths old.
> > > Should i just try a test with half the radiator blocked off? Not my
> > > preferred option but easy to test.. Or remove the fan blades (tempting
> but
> > > harder)
> > > If the temp became more 'normal' you would have to say that its 'over
> > > radiatored' wouldn't u?
> > > The big question is what effect is this gonna have in a sprint situation
> > > where often getting enough heat into engines, brakes and tyres is the
> > major
> > > problem?
> > > Sorry for all the questions and thanks in advance.
> > > cheers
> > > Mick
> > >
> > > www.datsun1600.freeservers.com
> > >
> > >
> > >
> >
> >
>
>
