Hey Steve and Ted;  Finally got the by pass hose restrictor in the T- bird, took a ride along coast, about 75 deg. and LOTS of traffic-- well it looks like I gained about 10 degrees!!  Original gauge and Auto Meter underdash, both read cooler than before. drilled a 3/16 hole in the plug-- as per Ted and also drilled extra holes in Stat. as per Steve.  Plesantly surprized.  Thanks for all the help from everyone on this site,  I always learn something!!!   God Bless    Eddie

Eddie

Lake Forest, Ca. 92630

Eddie - I'm glad to hear a favorable test report - my outfit is still buried in the garage. Finally got both of the "Jet-Hot" coated manifolds installed and just idling, there is a big change in the radiated underhood temperature. And the outside temp is siupposed to get up to 83° this week, better be getting my act together soon...

You've got the smaller pulley on your waterpump drive don't you? And a fan clutch set-up? if so, who did you get it from? Does it operate on "speed" or a bi-metal temp actuator?

My current set-up just has direct drive with the smaller pulley - six blade fan - and the noise level is considerable at idle. So I can imagine where that will go when I get it going on the freeway...When I mentioned this to an engineer I work with, he sent me this link....

http://www.rossairworks.com/content/view/19/16/

...and told me that there are some pretty slick B-W fan drives on some of the diesel trucks these days. There is a "cross arm" rigid electrical lead that crosses in front of the fan and attaches to a small bearing on the nose of the fan blade/electric clutch assembly. When a separate thermocouple controller determines the need for the fan - a relay turns it on. Very clean - mechanical fan - electric "On-Off". Could be temp controlled on the street  - and switchd off at the track.  

 
 Steve Metzger       Tucson, Arizona

Hey Steve;  Yes I have the smaller pulley from Concours and The clutch fan set up from Casco.  Has Thermo spring, the better clutch type. Have been in over 100 deg temp and not had a problem, well worth the cost.  Steve I also have A/C, but have the condensor assembly under the right front fender.   Used the remote condensor with electric fan,  from a NPR tilt cab truck--  this way I don't have the condensor heat going into the rad. Been on now for 4 years.  Gotta Drive Cool Man!!    many Thanks for everyones help.  God Bless    Eddie

Eddie

Lake Forest, Ca. 92630

Hi Eddie & Steve,

I'm following this topic with interest. Where exactly did you place the restrictor? The bypass hose is the 5/8" hose from the water pump back towards the block?

regards,

Brian - 56 T-Bird

Woodinville WA

I have a couple of mates with overheating dramas on rebuilt engines and new radiators. Our summer temps here reach the stratosphere anything up to 112F - not quite death valley I know but certainly uncomfortable for these old girls.

I will pass this info onto them and hopefully it well help their problems disappear.

Our winter temp never goes much below 40F even on the coldest day or night.

I had never thought of restricting the 5/8 hose to help in cooling but it certainly makes sense.I must second the sentiment that there is a wealth of information on this forum for us all and thank you all for your input.

Regards




Rick - West Australia
Do Y Blocks Downunder run upside down? Gravity Sucks!!

Lets see the full expanation of this restrictor.Nothing in previous discussions that I could find.Would like to know what was done and why?

  

I'd also like to see some more feedback before I get out the 3/16 drill and go crazy. The last time my thermostat stuck closed, I was trapped in heavy traffic on a super-hot day, in a VERY bad neighborhood. I'm hoping the extra holes (plus running the heater) would allow me to get to a safe area before a head gasket lets go. But, slower warmups will likely reduce longevity somewhat?

6 VOLTS/POS. GRD. NW INDIANA

Its not rocket science to alter thermostat flow to suit different heat and temp ranges. Keep in mind the thermo was designed to initally stop coolant flow to bring engine to operating temp then snap open within a temp range generally 160-180 deg, THEN become a controlled flow restriction to move the coolant through the designed cooling system .i,e radiator plus fan air flow. BUT that is in a perfect clean unblocked radiator, block, water passeges, correct fan size and fan pulley!. Alter any of those by either change or normal radiator and core blockage etc will then reduce the cooling efficency of the cooling system. As most folks generally look for the quick fix and half assed push a hose into rad & block to clean it out, it doesnt do a lot, its fortunate that the thermostat is easily accessable and the flow can be altered, just like rejetting a carb. Over the years i have modified thermostats and cooling systems to suit the heating situations involved in many vehicles.  Teds reducing the flow through the bypass is another way of helping, and is simple if you regard adjusting the coolant flow rate by adding more holes in the thermostat restriction, sort of tailor making the restriction to allow for what ever flow reduction there is from the condition of the system. In a similar way, altering speed of flow volume by pulley diameter change or fan air flow rate by different fan sizes etc, temp changes can be made to suit your car and climate, but do 1 step at a time to be able to measure change. Its only my opinion from from years of working on cars. best regards bill.

  AussieBill            YYYY    Forever Y Block     YYYY

 Down Under, Australia

Brian and Mark - This is just a simple change to how water flows through the engine. The bypass hose is the way for water to "short circuit" back to the waterpump when the engine is cold, and the thermostat is closed. It is a rapid warm-up device.

When the engine is warm - thermostat open - water is still bypassing the radiator via this route. A very short hose - a size most of us have around the household for use in the yard - is directly connected to pump suction and running hot water back into the engine. Running this flow through the radiator instead can add cooling. Eddies car showed approximately a 10°F drop.

Using a partial block of the bypass can make this happen. I used a 3/8 brass pipe plug with a 3/16 hole drilled through it. To make sure the pump was not starting  up cold against a complete "deadhead" - some holes were drilled into the thermostat as well. The 3/16 plug hole was suggested by Ted as a way to insure that air bubbles trapped in the front cover of the engine when it is stopped - had a way back up to the intake manifold.

This is a "Robertshaw" style of thermostat and you can buy them - premodified by Stewart Components - or drill them yourself. There are 3 x 3/16" holes added into the poppet as shown here. If you have a restoration type car - no one will ever see the modification - but cooling will be enhanced.

 
 Steve Metzger       Tucson, Arizona

What is the part # for the modified 180 degree thermostat From Stewart Components ? The website was a little unclear.

Pete