All the input is appreciated!  Today I raised the coil another 1/4 in., and bought my own IFR thermometer.  Unfortunately the ballast resistor on the shelf has a broken insulator that the winding goes around, so may have to get another to try the stock coil/ballast setup.  Need one anyway to carry in the glove box.  Didnt have a chance to do anything else.  Lash should be fine, but will check again, this time at 180.  Previously have always adjusted lash to cold spec.

The cold running temp is a continuing puzzle.  The same temperatures occurred with the previous low compression engine, using a big 4 row stock 1946 new core radiator.  Put in a new engine with much higher CR, a relatively small 17X19 core alum. rad, and the same thing.  I talked to a mech. engineer/car nut about it last year.  He thought the cold temp was due to the low 7:1 or so CR.  It is now clear that wasnt right, because the CR is approx. 9.2:1.

I am lucky to have one of Franks aluminum timing covers and water pumps.  Several years ago when I was installing them, there was interference in the area of the timing cover water scraper (dont know what it should be called), and the pump impeller.  After some work clearance was achieved with a very close tolerance that could be measured in thousandths.  Perhaps the result is a super efficient, maybe too efficient pumping action, leading to cool running temps?  Sounds a little far out but nobody else has been able to explain the phenom. 

Mike

Mike, located in the Siskiyou mountains, Southern, OR 292 powered 1946 Ford 1/2 ton, '62 Mercury Meteor, '55 Country Squire (parting out), '64 Falcon, '54 Ford 600 tractor.

Mike:

Where is the temperature sensor installed?

John - "The Hoosier Hurricane"

I’ve found that the engine temperature reading on a Y is lower than the thermostat rating if you are taking the reading at the back of the head in the stock location.  I typically see about a ~10° to ~15° difference in temperature readings from the rear to the front of the engine on a Y.  Moving the temperature sensor to the heater water port right behind the thermostat typically gives a more accurate reading or it comes closer to matching the rating of the thermostat.

Lorena, Texas (South of Waco)

Ted,

       That makes absolute sense. the coolant continues to absorb heat as it travels to the front of the motor. The hottest point should be at the thermostat. I can easily believe a 15 degree rise from the back to the outlet.

         Mike, I intentionally kept the impeller to the timing cover dimensions tight, but had some issues with the machine shop not locating the mounting holes in the pump/timing cover accurately. I finally had to change suppliers because of that. I hand fitted the pumps to the cover just to avoid the issue. Not sure how yours slipped through, but I apologize, you shouldn't have had to do that.   

Frank/Rebop

Bristol, In ( by Elkhart) 

John, the sender is on the DS in rear of head.  Today I'll do some testing with the handy thermo and report.  Also will try some slight adjustments on idle screws to find the happy compromise. 

Mike, located in the Siskiyou mountains, Southern, OR 292 powered 1946 Ford 1/2 ton, '62 Mercury Meteor, '55 Country Squire (parting out), '64 Falcon, '54 Ford 600 tractor.

I usually try to get my IR readings right on the thermostat housing. That has to be the hottest water in the engine. My other favorite spot is the waterpump inlet - temp in / temp out and the ambient outdoor surrounding temp (air going into the radiator and carb inlet) usually tells the tale.

 
 Steve Metzger       Tucson, Arizona

I find my 312 Y block in my 57 T-bird runs better when it is hotter. When the needle is pointing about 2/3 rds in the white band area the cars pulls away from a light with a clean, crisp acceleration and seems to be a bit more power. I am running a 170 wide opening thermostat from Casco.

Ted,



Funny, it never occurred to me to trial-fit the alum. components when I received them a few years back (put aside for inevitable rebuild).

The pump-to-spacer clearance is VERY tight. You said was intentional, but did not explain (?). As is, I would certainly have to move the pump around and feel for contact before final gasket-seal/torquing.

On the cover, though I see evidence of finish grinding, if not a T-Bird I would be in big trouble without further alteration! Not even close.

I also notice quite a divergence in the way bolt holes & and casting edges of the 3 items align. I see my FoMoCo parts do not line up perfect either though, and the wider gaskets do sort of break up the misalignment some.



So, should I grind on the cover some more to make some breathing room, or just pre-assemble & seal before final cover install? What should target spacer-to-pump clearance be?

6 VOLTS/POS. GRD. NW INDIANA

Today was another learning chapter in the book of Y's.  Too bad the chapters arent in sequence.  Went for a short ride and found a shade tree when the gauge hit 155:

DS rear of head right next to sender     158

DS front of head 182

PS front of head 188

Intake crossover 160

Intake water jacket 170

Water port behind thermo housing 167

Thermo housing 170

Carb body 101

Coil 122

So, as suggested by Ted and John, the water gauge is approx. 15 deg. cool due to its location.  And the rough idle doesnt start at 180, but 195 or 200 deg., which seems to make more sense. 

I'll move the sender to behind the stat when the new manifold is installed.  In the meantime the fan will get switched on earlier, and maybe that alone will take care of rough idle.  The carb and coil temps seemed good, but dont have anything to compare them to.

A couple years ago a friend checked the rear DS head & thermo housing temps, and they were virtually identical being below 160 degrees after I had driven to his house 12 miles away.  But the old engine had some weird issues.

Thanks to everyone for their help!

Mike

Mike, located in the Siskiyou mountains, Southern, OR 292 powered 1946 Ford 1/2 ton, '62 Mercury Meteor, '55 Country Squire (parting out), '64 Falcon, '54 Ford 600 tractor.

My gauge is the same. It reads 160 in the cab but just before the thermostat it is about 188 according to ir.


Lawrenceville, GA