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The recored radiator for the 1931 Series 43 is ready to be picked up. I will face the issue of getting the shutters working so what about adding a thermostat? As I did not remove one, I assume the shutters were intended to be the temperature control. Maybe some have added a thermostat and just open the shutters manually?
Randy, I’m confused about your question. The shutters ARE the thermostat, they’re controlled by a heat sensitive bellows that bolts into the top tank of the radiator.
If the radiator has been changed and no longer has this control, then your only solution is to block the shutters open and leave them like that.
The shutters on my 43 are blocked open, I’ve driven it like that summer and winter and had no issues.
I’d also suggest taking a freeze plug the outside diameter of your upper radiator hose, drill a 5/8″ hole in it, and insert it into the upper end of the hose. This will slow down the water entering the top of the radiator, and keep the radiator from overflowing when you suddenly reduce rpm of engine. I know some might say that’s crazy, but my car would overflow if I took foot off pedal at speed, the plug solved that issue totally.
David,
When you mention a Freeze Plug, do you mean something like a 1.75″ to 2″” Stainless Steel Fender Washer (the OD being the ID of the hose) with a decent sized hole (easily made larger) inserted at the end of the top radiator hose next to the radiator inlet?
I believe that is what I have (or had) in my Series 80 to reduce water flow / water puking.
Peter”
Interesting idea on the freeze-plug to restrict flow.
I have shutters on my ’32 Packard and although I have the original radiator the thermostatic bellows does not work. David is right that blocking the shutters open appears not to be harmful. Last I checked new bellows are expensive.
But since I like to drive the car in the cold weather I wanted to allow the engine to warm up quicker and to maintain a temperature in the driving range. Hard to achieve when its below freezing.
So I designed a manual hand crank which allows me to open and close the shutters from the inside of the car. My car has glove boxes on either side of the dash so I could hide it in there. Simple and works great. But you do need to pay attention if you start out with the shutters closed. Before I got used to it, I did peg the temperature gauge a couple of times.
Dave, I had may radiator rebuilt/recored and I understand the new core is cellular, but a different cell from the original. I did not remove the shutter device. I know the shutter thermostat does not work so it will need repair but it seems a good time to add a normal thermostat to the coolant outlet on the engine, IF this is one recommended way to best control engine temp, which is why I asked.
Dave, Peter: I hear/read regularly about coolant puking. My Series 80 has never done this but it does have a modern 160 F thermostat in the engine coolant outlet.
I have to think a while about the situation described: the engine slows suddenly, which means the pump slows also, which means the flow slows, but the increased flow overfills the top tank of the radiator. Maybe the issue is: the engine has internal heat content and flow at a fairly high level due to being under load, but the coolant flow suddenly slows, causing the coolant in contact with the hot internal engine surfaces to locally overheat and boil, burping/pushing coolant toward the radiator mostly toward the top but likely in both directions? I know flathead engines put a lot of heat into the cooling system when loaded, compared to ohv engines. This could be a phenomenon enabled or aggravated by the cooling system not being pressurized, as pressure will increase the boiling temp. An orifice in the engine outlet to the radiator would certainly slow whatever flow is being pushed that direction, no doubt. If there is localized sudden boiling in the engine block or head, it would push coolant toward the only way out: toward the radiator top.
In summary of what I read here: the bellows systems which position the shutters seem to be troublesome and expensive to set right, and frequently the shutters are opened and left that way, and that will work for me. I am studying the shutter systems and will perhaps repair mine once I understand them better. Thanks everyone!
All the parts to make your system work correctly are available and easy to install. Why not keep the car correct? If it is all apart and has a new core it only makes sense to finish the job correctly. The parts are not that expensive and bellows and linkage are available as well as some other parts. Cislak advertised them in the last six months. Give him a call if you need help. Enjoy your car! Ed
Even with the shutters working correctly, I put a water-thermostat in the hose casting on the cylinder head.
With two 1/8″ holes drilled in the thermostat flange, there is enough circulation for warming up quickly. The thermostat stops the circulation of all 6-8 gallons of coolant, until it is needed to cool the engine.
Over cooling an engine is very tough on the rings and cylinder walls.
Greg Long
Greg I agree on the advantage of proper operating temp (i.e. not too cold). The thermostat I added to the Series 80 has a couple holes drilled as you state and the temp comes right up but I haven’t overheated so far. It did great in St. Louis last year.
I drill the 1/8″ holes on all of my thermostats. It helps let a little coolant flow at all times but more importantly there is no worries of an air pocket in the head. For the Pierce I had a small recess machined into the water neck so the stat would fit in it nicely against the head.The holes allow the air to bubbles to work themselves out. The thermostat also helps slow the burp out the overflow on deceleration. Still had a little dribble at times and totally eliminated that by getting rid of antifreeze and going to water wetter so there is no corrosion. The antifreeze can foam up and cause it to overflow. Didn’t have to add a drop of water all summer since the changes.”
The 1/8″ holes are necessary because there is no bypass circuit built into the block.”
When you mention a Freeze Plug
Peter, when I say a freeze plug (which is a misnomer as many of you know), it’s the cup shaped steel piece that goes into a casting hole in a block. The holes had to be there for casting purposes, and get a plug, and common lore is that it’s a “freeze plug” to let go if water expands in the block. That isn’t the purpose, of course, it’s just a byproduct of the manufacturing process.
I’ve seen all the discussions about water puking out the top of the radiator, and the talk of water velocity and that it can’t be that because the water pump is moving X amount of water and so forth. All I can tell you is that the restriction in my upper hose made the car quit puking coolant out the radiator and the car runs very nicely in the mid range of the temperature gauge…..I probably don’t run it enough in cold weather to worry about Greg’s mention of running too cool…
Greg is correct, running the engine too cool advances engine wear by 200 to 300 percent…….. but todays modern oils, valves, pistons, and rings are much better than fifty to ninety years ago. The block on a Pierce is very good material and doesn’t offer any issues. Running the thermostat as Greg does is fine, EXCEPT today the cheap thermostats available are just terrible quality so be sure and buy one from a speed shop that sells ones made in the USA. They run about 25 bucks, and are worth every penny.