There are a group of T-Series owners in Utah that attend the GoF West every
year. If you look at the map you will notice that when we drive to Canada we
cross desert, when we drive to Northern California, we cross desert, when we
drive to Southern California, we cross desert. And every year the event is
held in June, July, or August. It gets hot out there.
Most of us have blocked the water flow through the bypass and found the
temperature drops around 7-10 degrees.
One driver drilled a small hole in his blockage to allow for a trickle of
water, the rest of us have completely blocked ours. Don't see any difference
in the wear on the engines.
Floyd Inman
'53 TD
----- Original Message -----
From: Lew Palmer <lpalmer@mn.mediaone.net>
To: Larry Cogan <woodrat@spacey.net>; Lew Palmer <lpalmer@mn.mediaone.net>;
Stuart Keen <simbafish@home.com>; MG T Digest <mg-t@autox.team.net>
Sent: Thursday, July 06, 2000 4:23 PM
Subject: RE: Thermostat
> I can't disagree with simply "restricting" the coolant flow rather than
> blocking it off completely. It's just that I have been running that way
for
> years with only other non-bypass issues giving me problems.
>
> I only relate what has worked for me here in Minne"snow"ta.
>
> Regards,
> Lew Palmer
>
> -----Original Message-----
> From: Larry Cogan [mailto:woodrat@spacey.net]
> Sent: Thursday, July 06, 2000 4:12 PM
> To: Lew Palmer; Stuart Keen; MG T Digest
> Subject: Re: Thermostat
>
>
> Lew: Im not an expert on this, for sure, but let me relay the essence
> of whats been a recent long thread on the T-ABC list. (Of course the
> XPAG engine is the same in the TC.) Some very smart guys have made
> the point that blocking off the by pass completely is not good, if a
> thermostat is installed. The reason has to do with localized hot
> spots at the rear of the engine which develop because if the bypass
> is totally blocked, there is no coolant movement for a period of time
> before the thermostat opens. The consesus is to place a restrictor
> plate in the bypass with a 3/8" hole in the plate. This then of
> course allows some movement of coolant to take place while waiting for
> the thermostat. Additionally, if the thermostat fails closed, you
> have a much more "benign" temp rise, hopefully allowing you to see the
> problem before meltdown.
> Leave it wide open or put in a drilled plate. Regards, Larry
> ----- Original Message -----
> From: Lew Palmer <lpalmer@mn.mediaone.net>
> To: Stuart Keen <simbafish@home.com>; MG T Digest
> <mg-t@autox.team.net>
> Sent: Thursday, July 06, 2000 4:22 PM
> Subject: RE: Thermostat
>
>
> > Stu,
> >
> > Although Minnesota isn't exactly Florida climate, we do a lot of
> touring in
> > the hot summer months (90 degrees). Here's what I do:
> >
> > 1) I completely block off the bypass. I simply cut a solid gasket
> from a
> > plastic pop bottle and place between the thermostat housing and the
> bypass
> > elbow.
> >
> > 2) I make sure all water passages in the block and radiator are
> clear.
> > Especially prone to blockage are the areas behind the
> expansion/access plugs
> > in the block.
> >
> > 3) I make sure I have the minimum possible amount of clearance
> between the
> > water pump impellor and pump body.
> >
> > 2) I add 1 quart of NAPAKool to the radiator into a 50% mixture of
> > water/antifreeze. (A lower ratio is better (more water than
> antifreeze), but
> > unless I want to constantly change mixtures during the year, I can't
> because
> > of freezing temperatures during the cold months.)
> >
> > 3) I drive with no concerns.
> >
> > I am only using a stock, modern thrmostat (don't remember the
> number, but it
> > is a 165 degree unit) that fits the opening.
> >
> > And, yes, water flows from the engine into the top of the radiator
> and out
> > the bottom. (Remember, hot water rises, cold water sinks). This
> gives an
> > assist to the water pump because of thermosyphon action. Many
> pre-war MGs
> > never even used a water pump, relying solely on thermosyphonic
> action.
> >
> > Regards,
> > Lew Palmer
> >
> > -----Original Message-----
> > From: owner-mg-t@autox.team.net [mailto:owner-mg-t@autox.team.net]On
> > Behalf Of Stuart Keen
> > Sent: Thursday, July 06, 2000 2:54 PM
> > To: MG T Digest
> > Subject: Thermostat
> >
> >
> > The original thermostat in my 1951 MGTD MKII is defective and a
> similar
> > type is no longer available. What should I do? Please bare with me
> as I
> > explain in somewhat detail; history and what has been done to date.
> >
> > When I purchased the TD, the thermostat was the removable type, it
> had a
> > center brass bolt which bolted to a cross arm in the upper parts of
> the
> > housing. The bolt was affixed to 1) a 1 7/8 inch diameter, 5/8 inch
> high
> > brass band (which affected the flow in the bypass tube) and 2) to
> the
> > thermostat diaphragm. The bottom of the diaphragm was bolted to a 2
> inch
> > diameter flat ring via three supporting arms. This lower ring fitted
> > into a grove in the housing. To install, the thermostat was inserted
> > through the bottom of the housing until seated and the top bolt was
> > inserted in the crossarm and the nut tightened.
> >
> > The thermostat was inoperative when I purchased the car. The
> previous
> > owner had soldered the diaphragm in the compressed (open) condition,
> > saying that driving in Florida, the thermostat would be open all the
> > time anyway. He emphasised the need for some restriction in the
> water
> > flow path.
> >
> > When the engine was rebuilt in January, the machine shop saw the
> > soldered thermostat and junked it; ie. returned the TD with no
> > thermostat installed. I have the old thermostat but it is in pieces;
> i.e
> > butchered.
> >
> > Being advised I should not drive the TD without a restriction in the
> > water flow, I ordered a thermostat from Moss (also tried Abingdon,
> but
> > they had none available). The Moss thermostat was completely
> different,
> > just a flat circular plate with a small thermostat system protruding
> > from the center. The replacement fit loosely in the grove in the
> bottom
> > of the thermostat housing, so I flattened the raised edge to make it
> > more snug.
> >
> > I am concerned about the thermostat since I am about to make a 5,000
> > mile trip in the TD. I was about to order a housing with
> non-removable
> > thermostat from Moss, but would like advice first to know if this
> > expense is really necessary.
> >
> > Last night I read over 200 archived messages about thermostats. The
> > common thread is that you should have some restriction in the bypass
> > outlet. The original unit provided this with the brass band, but the
> > Moss replacement does not provide any restriction. Is control of the
> > bypass really necessary if I am driving in a hot climate all year?
> >
> > I ask if it is really necessary because I have now driven approx
> 4,000
> > miles with the Moss replacement thermostat installed and with no
> > restriction in the bypass outlet. Much of the driving has been in
> > Florida, but even here my water temperature gauge (rebuilt several
> > months ago by MoMa) never registers higher than 83 deg C, usually in
> the
> > mid to high 70s. The water temperature seems to be okay, so should I
> > even be worrying about the quasi thermostat installation in my TD.
> Am I
> > just being a perfectionist and a worry wart?
> >
> > I am not even sure I installed the replacement thermostat correctly,
> but
> > it seems to work. The unit is marked with the words "TOP" on the
> ring,
> > with the spring and housing protruding below. This is how I have it
> > installed. However, there is an annotation on the side saying "Flow"
> and
> > an upward arrow. What is the direction of water in the system? Is
> water
> > coming from the top of the engine, UP into the thermostat housing
> and
> > then into the top of the radiator to cycle downward and be cooled.
> For
> > some reason I thought it was the reverse. Shows how little I know
> about
> > cars.
> >
> > I am listening to all advice, such as
> >
> > 1) leave well enough alone, the water temperature seems to be okay
> now
> >
> > 2) order a housing with non removable thermostat from Moss
> >
> > 3) put some kind of restriction across the bypass opening as
> suggested
> > by some of the archives.
> >
> > Thanks for your patience in reading all this detail, for putting my
> mind
> > at ease and for any suggestions.
> >
> > Stu Keen
> > Venice, Fl
> > simbafish@home.com
> >
> >
>
>
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