[Healeys] Failsafe thermostats

Bob Spidell bspidell at comcast.net
Mon Dec 30 17:59:13 MST 2024


re: "EC and OT rise rapidly when no airflow as MS describes. rg thinks 
that we under estimate the cooling effect of cruising airflow on the 
actual engine block surface"

I don't underestimate it. Both my Healeys, BN2/100M and BJ8, behave 
exactly the same: On cool days--70degF ambient or less--the engines will 
not reach thermostat set point (180) when cruising. Both heat up when 
sitting at idle. Both run at 180 or slightly above on warmer days, but 
start to heat up quickly at idle and can go to 212. I can only attribute 
the difference to airflow temp.


On 12/30/2024 10:12 AM, Al Fuller wrote:
> Roger - sounds interesting. Can you share pictures of how the 
> information is displayed?
>
> ________________
> Sent from my phone
> Best Regards,
> Al Fuller
>
> On Mon, Dec 30, 2024, 8:30 AM Roger Grace <roggrace at telus.net> wrote:
>
>     Yes, no doubt that idling after a high speed run when the engine
>     was working hard with increased losses is the worst situation for
>     our cars. Another technique to help the "reserve" is to install an
>     overflow recovery tank that ensures you start off with a full
>     header tank. This is a relatively simple project and works well.
>     I am a bit of a temp nut. On my BJ8, display via multiplexed
>     switches :
>     WT - Smiths std gauge
>     OT- oil temp at filter
>     EC - engine compartment near carb intakes
>     TH - top hose water temp
>     Input ambient to rad and cockpit temps just for interest.
>     5 Blade TX fan; oil cooler; EWP electric water pump - manually
>     switched; 160F thermostat - agree with Michael above; rad
>     recovery. As per Harold have 2 x 3/16 holes in thermostat; AL
>     finned sump.
>     Most interesting observations are:
>     Oil takes longer than we think to get close to operating temp at
>     least 30 min but depends on ambient.Often long after the stat. opens
>     TH is generally 10F lower than the WT reading
>     EC and OT rise rapidly when no airflow as MS describes. rg thinks
>     that we under estimate the cooling effect of cruising airflow on
>     the actual engine block surface. Airflow is somewhat limited as a
>     big chunk of metal obstructs and no easy exit. Often wondered if
>     an extractor fan would help - hence the louvres on the hood and
>     sides to get the hot air out for competition cars. My car runs
>     badly when EC is above 155F - becomes too rich for the inlet air.
>     Use the EWP when approaching traffic as above - does not reduce
>     temp, but seems to prevent further increases. Important to
>     anticipate. EWP is really good for controlling heat soak after
>     cutting the engine.
>     Recently removed an electric rad pusher fan as no real benefit and
>     an obstruction to incoming air. Rad inlet deflectors are important
>     Hi ambient of course is a big factor for rad and block cooling.
>     Monitoring OT is very useful and easy to relate to when driving.
>     rg
>
>
>
>
>
>
>     On Sat, Dec 28, 2024 at 9:42 AM Michael Salter
>     <michaelsalter at gmail.com> wrote:
>
>         Like most 100 drivers I have struggled with overheating
>         problems on occasion.
>         The worst situation is when stopping for gas or becoming
>         stalled in traffic on the highway after running at high speed.
>         On those occasions when I do drive in cooler temperatures the
>         temperature usually reaches 75 - 80 degrees C (167 - 176 F)
>         even without a thermostat although the warm up is a little
>         slower.
>         The advantage of running at this cooler temperature is that
>         the system seems to have a larger "reserve" when the above
>         traffic problems occur.
>         I found that the indicated temperature (which is accurate),
>         runs 5 degrees C  higher even when using a 165 degree bellows
>         or wax pellet type thermostat. I suspect this is due to the
>         slight restriction even when the thermostat is fully open.
>
>         M
>
>         On Sat, Dec 28, 2024 at 8:32 AM Michael Oritt
>         <michael.oritt at gmail.com> wrote:
>
>             I need to replace my thermostat and I see a lot of
>             negative reviews for "Failsafe" units--sold my Moss and
>             many others--which are designed to fail in the open mode. 
>             What is the collective experience with these?
>
>             TIA--Michael Oritt
>             _______________________________________________
>             Support Team.Net http://www.team.net/donate.html
>             Suggested annual donation  $12.75
>
>             Archive: http://www.team.net/pipermail/healeys
>             http://autox.team.net/archive/healeys
>
>             Healeys at autox.team.net
>             http://autox.team.net/mailman/listinfo/healeys
>
>             Unsubscribe/Manage:
>             http://autox.team.net/mailman/options/healeys/michaelsalter@gmail.com
>
>         _______________________________________________
>         Support Team.Net http://www.team.net/donate.html
>         Suggested annual donation  $12.75
>
>         Archive: http://www.team.net/pipermail/healeys
>         http://autox.team.net/archive/healeys
>
>         Healeys at autox.team.net
>         http://autox.team.net/mailman/listinfo/healeys
>
>         Unsubscribe/Manage:
>         http://autox.team.net/mailman/options/healeys/roggrace@telus.net
>
>     _______________________________________________
>     Support Team.Net http://www.team.net/donate.html
>     Suggested annual donation  $12.75
>
>     Archive: http://www.team.net/pipermail/healeys
>     http://autox.team.net/archive/healeys
>
>     Healeys at autox.team.net
>     http://autox.team.net/mailman/listinfo/healeys
>
>     Unsubscribe/Manage:
>     http://autox.team.net/mailman/options/healeys/alfuller194@gmail.com
>
>
> _______________________________________________
> Support Team.Nethttp://www.team.net/donate.html
> Suggested annual donation  $12.75
>
> Archive:http://www.team.net/pipermail/healeys http://autox.team.net/archive/healeys
>
> Healeys at autox.team.net
> http://autox.team.net/mailman/listinfo/healeys
>
> Unsubscribe/Manage:http://autox.team.net/mailman/options/healeys/bspidell@comcast.net
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://autox.team.net/pipermail/healeys/attachments/20241230/a7a2513f/attachment.htm>


More information about the Healeys mailing list