Gun Jam

Ive always noticed that engine temps seems low in the winter. Its been extra cold here for central ca. the last week or so. Its starting to bug me that the temp never gets to indicated normal on the stock 66 temp gauge. It sits just above the bracket on the cold side.

In summer it runs right in the middle and I know the gauge is accurate.

My question is. If Im running a 190 T stat and the water temp doesnt appear to be reaching 190 how is cold water entering the block?

That bypass hose that runs from the water pump to I believe below the T stat housing does it actually allow that much water to by pass the t stat?

Can a something be added to restrict the amount of bypass?

Thanks

-Gun

jlg2002

yep, that's exactly what the bypass hose does, scary huh!!! your t-stat could be open too, you may want to pull it and look. You could go down to a 160 thermostat (if you can find one) or you could figure out a way to restrict airflow through the radiator (like the diesels with flaps) I suppose you could put a stainless washer in the BP hose at the thermo housing nipple.

Gun Jam

Im trying to boost engine temp...not sure how using a 160 t stat is going to help. ?

Why would they use such a large bypass hose? Its like 3/4" garden hose...and what is its purpose? I like the washer idea. If Ive got a 3/4" 100 deg f head of water zipping past the t-stat its a small wonder it wont reach operating temp.

EDIT: after looking closely at it, it appears that it simply allows water block water to circulate through the pump and back into the block so the pump does not dead head. SO

1) If the T-stat was closed it would not allow hot water to dump from the block into the top of the radiator

2) because the T-stat is closed picking up cold water from the lower rad hose would be quite difficult because it would create a vacuum this would prevent much if any cold water from entering the block

3) if 1 and 2 are true then its a t-stat issue???

Thanks

-Gun

jlg2002

Yeah I thought about that 160 comment later after I made it. When I wrote it I was thinking you could give yourself more comfort in the fact the coolant would most likely be moving thru the thermostat instead of the bypass hose. It definitely won't make it run hotter.
I see your logic but offer: my experience on vehicles with stuck closed t-stats is the engine gets overheated, the coolant bubbles (boils) profoundly in the engine, hoses, rad and eventually blows the pressure cap. On the other hand, if the t-stat is stuck partially or fully open, it doesn't allow the engine to come to temp in the cold months and is undistinguishable in the warmer months.

guitarman376

There are hotter thermostats available, why not just try one of those?

Gun Jam

because im already running a 190 or 195 (which is what I think these cars shipped with new) and because im convinced that coolant temp isnt even hot enough in the first place to open a 190 so a 200 for example would do me no good.

I'll take true reading of the T-stat housing tomorrow and go from there.

Thanks!!

-Gun

fastbackford351

What's the problem? Is the car running poorly?

If it is really bugging you then the easiest way I know to heat it up would be to put a piece of cardboard or something in front of the radiator ala a truckers radiator blanket. It'll damn sure heat up then.

When my car runs cooler than usual I figure I'm putting some good mojo in the bank for when it's 110 out on the asphalt & stuck in traffic and the cooling system is really strained.

Gun Jam

I actually got 190 a the t-stat housing...I wonder if my gauge has changed.

I guess its all gravy then.

Thanks for the help

jlg2002

You can always get a ohm reading on the sender with it a temp to see where it is. as i recall the circuit resistance is fairly linear from cold to Hot.