Air Pocket? Sometimes it's hard to get all the air out This is just a guess

Has anyone ever tired to drill a small hole in the thermostat to let the air out?

 

i'm sure you made sure you didn't put then in backwards. had to ask.

 

no it isnt backwards all i can think of is air. i took it back out and put it in a pot of boiling water and it definitly opend, i think im gona fill the block up w antifreeze tomorow then reinstall it, ive never had this problem b4 i think ill stick to upholstery and body work and leave the mechanics to the prof lol

 

I'm with 12-Pack on this one. I had a little Ford that was really bad about the air pocket issue. Most thermostats have a very tiny hole or a notch at the edge of the moving disc seating area to let out the trapped air. If you can ever get it hot enough to open your thermostatfor the first time, that'll also fix it, but I prefer the vent trick.
If yours doesn't have such a vent, try drilling a hole with the smallest twist bit you have. Your best bet would be on the stationary disc.
I have considered inserting a small piece of water soluble something or other between the seats to keep them slightly open, but you might as well just go with the vent trick.

Best of luck,
Greg

 

Jacking up the front end will help get rid of air pockets. You can also drill a small seep hole in the t-stat. Some t-stats actually come this way.:tu Also, Is the water pump new? I have seen a few Chevy water pumps with the impeller blades rotted off.

 

Jacking up the front end will help get rid of air pockets. You can also drill a small seep hole in the t-stat.

I take one of the thermostat bolts out, when I refill a radiator. Allot faster than jacking the car up. Drilling a hole is not necessary, if removing the bolt.
One thing, never run an engine without a stat. They need that to slow the coolant, to pick up the heat from the engine. If your engine don't overheat without a stat, then you have a circulation issue. Most likely a blocked radiator.

 

Over Heating ?

I might as well put my 2 cents in for what its worth, LOL
To much antifreeze is not good, one gallon in a small block is plenty for cooling.
Watch your bottom radiator hose and make sure it is not collapsing when your stat opens and shuts, I had the same proplem, sure enough the bottom hose was collapsing on and off each time the stat opened up, just a thought.
good luck.
Ron Holz , in WA.

 

12Pack.....thats just what I did and "air pocket was correct.....

 

Something else going on...2 different stats = hot.
No stat = OK???

 

well,

heres my 2 cents worth

I agree, jack up front end, drill 1/8 hole in state, and use a 180.
I,d even drain a tad out, and while jacked up, ad coolent back with engine running, and let her run and even kinda over fill rad, some and let it circ, while running to get air pocket out of system.
let us know how you come out .

 

Buy a set of these,

http://store.summitracing.com/partdetail.asp?part=MOR-63440&autoview=sku

Pick the one that gives you your best temp and enjoy.

 

gconnsr. Tell us what these would be for, if it wasn't necessary to have some restriction (stat) in a cooling system ? These plates have the same restriction as an open stat.

Point is that coolant picks up heat and a certain rate. If the coolant moves too fast, it will not pick up the heat, to carry it into the radiator, thus engine over heats.

 

well i actually did both things last night, first i brought the thermostat inside and put it in boiling water to make it open up. it opend at around 210 deg and my girlfreind was asking me what i was finally cooking her lol. i let it cool and close bck up then i did it again and it opend right at 180. so this mornin i went to reinstall it but befor i did i filled the block up w coolent through the thermostat hole. oh and yes i am using a mixture of collent and water. put the thermostt all together and wala i hit 180 on the temp gauge and it opend up and the temp started to drop. i thank you all for youre help on this one:tu:tu:tu:tu:tu:tu:tu

 

The idea of getting the "FRONT END" jacked up is to get "TRAPPED" air pockets. I guess you didn't get that one! P.S. I run alot of my old cars with NO t-stat! I live in the desert where it hits 120+ and yes, it keeps them COOL!tdi

 

Relax. I have worked in the auto trade since 1967. I have some knowledge and experience here. I'd say if you are running a car without a stat, you may have a partly plugged radiator to be able to do this. But don't take my word. Ask somebody who knows.

 

Personally I don't care who you are or what you know. I wasn't giving you advice, I was trying to help someone else. I don't need a ******* contest, thats not why I use this forum. Just to let you know, I've been a master ASE mechanic for twenty five years, and have worked on just about every car known to man, But that really doesn't matter, I really don't care if you feel you are the world greatest mechanic and know all! In my word I can't stand narrow minded mechanics that think their way is the only way. Again, I wasn't giving you advice, and do not care if you are god himself. Doe's this about sum up my feelings for you?

 

Stop your wing big boy, you were wrong. Plain and simple. BTW The spell checker is free for all here to use.

 

It's ###-holes like you that keep people from wanting to help others, isn't it! It would have been way to simple for you to just post your suggestions like everyone else on this forum. Instead, you have to start **** with someone thats trying to help. Do me a favor and take the whole bottle of Ritalin that you seem to be so proud of.:tu

 

It's ###-holes like you that keep people from wanting to help others, isn't it! It would have been way to simple for you to just post your suggestions like everyone else on this forum. Instead, you have to start **** with someone thats trying to help.

I suggest you go to the refrigerator and get some ice. Full the sink with ice and water. Then soak your head for a while, then talk to me. OK ?

 

It's ###-holes like you that keep people from wanting to help others, isn't it! It would have been way to simple for you to just post your suggestions like everyone else on this forum. Instead, you have to start **** with someone thats trying to help. Do me a favor and take the whole bottle of Ritalin that you seem to be so proud of. Better yet, Make that bottle of Ritalin a double.:tu:tu

 

When Your Wrong Your Wrong



When you sobber up talk to me. OK ?

 

Wow! Now that was an impressive post! You are the man Chevynut.:tu

 

for those of us here to soak up new information, the moral of the story is that he had an air pocket in the system, yes?

I had an air pocket in the cooling system of my daily driver not long ago (03 ford explorer, 4.6L) and I learned the hard way about the "Fail-Safe Cooling" system that ford sticks on those mills... i was moseying along minding my own business, temperature reading perfectly normal, when suddenly bells and whistles start going off, and she starts bucking and coughing. On the side of the road i read all about "Fail-Safe Cooling" in my owner's manual . . . when the computer detects a high cylinder head temp, it protects the engine from damage by cutting off every other cylinder, in essence turning it into a Jake Brake i suppose, and the cool, uncombusted air keeps things from overheating.

I guess that steamy air pocket must have hit the cylinder head temp probe, because otherwise, the temperature was normal.

Worked the air bubbles out by squeezing the upper rad hose like a siphon for an hour or so, on the side of the road. FYI that late model thermostat in my explorer comes stock with a 1/8" vent hole drilled through it, with a small metal pressure-stopper (like a reverse drip-valve).

My Bel Air normally reads about 10 degrees higher than t-stat temperature setting, but since the discrepancy has been consistent through a few thermostats, I chalk this up to the the fact that the probe is plumbed into the side of the engine, rather than into the intake near the thermostat housing. (previous owner did this, I just changed it back this week during engine rebuild, we'll see if the reading changes.) I assume that because the fluid encasing the thermostat is 180 degrees, doesnt mean that the fluid at the rear of the engine is also 180 degrees. maybe someone has a thermodynamic law for this one.

 

My Bel Air normally reads about 10 degrees higher than t-stat temperature setting, but since the discrepancy has been consistent through a few thermostats, I chalk this up to the the fact that the probe is plumbed into the side of the engine, rather than into the intake near the thermostat housing. (previous owner did this, I just changed it back this week during engine rebuild, we'll see if the reading changes.) I assume that because the fluid encasing the thermostat is 180 degrees, doesnt mean that the fluid at the rear of the engine is also 180 degrees. maybe someone has a thermodynamic law for this one.

You're right, the temperature reading of a sender in the head is likely to be higher than the temperature reading at the thermostat housing. But keep in mind that your thermostat doesn't control the engine's maximum temperature...your cooling system does (fan, radiator, etc). The t-stat just keeps the temperature above it's setpoint.

 

Look at it design alone of the restrictive nature of the stat it self. The opening is one diameter, and the valve opening is another. If the stat wasn't designed to slow the flow, then why wouldn't the design be made to allow the whole volume of the housing opening ? In my humble view the stat was designed to regulate/restrict, what would be an engineering nightmare of design, to build and en engine with perfect flow.

One other reminder. I recall that the nature of this forum is family friendly. Not to beat a dead horse. Just that some have not read, or forgot what they read in the rules. This forum is by no means about one member and one member alone. We can learn from each other, given a little patience to try to understand there are others who do have a handle on what is being discussed.

 

Chevynut is correct that more flow = more cooling and heat transfer.

The restrictive nature of the thermostat is for manufacturing economy. It's much easier to build it with the ring on the od so that the butterfly or poppet has a surface to seal to, and to mount the mechanism.

The restrictive orifices do have a place. With a down flow radiator built like it is on a stock 55-57, the flow from the thermostat/top radiator hose is pointed right at the radiator cap. The flow pressure from this can overcome the cap when the water pump flow is high. When this happens, a simple flow restrictor in place of the thermostat (or simply using a thermostat), can reduce this tendency. If the radiator cap neck is relocated, or a high pressure cap is used, the flow restriction may not be necessary. This is what the circle track racers did in the old days. The presssure cap problem is not due to overheating, but it can cause overheating once enough coolant is lost.

If a crossflow radiator is used, then a restriction is no longer necessary to keep from overcoming the radiator cap, as the cap on a crossflow radiator can be positioned on the low pressure tank of the radiator.

I hope this puts things into perspective. There might be a "real" reason to use a restriction, but there are ways around needing to do it. And the reason to have the restriction is NOT to increase cooling, except in an indirect way.

One more thing, I'll relate a real world experience. I had a situation where my Nova would warm up and level off in temperature just above the thermostat setting just as you would expect. When I'd hit about 70 mph on the highway, the temperature would start rising, and it would keep rising the faster I drove. When I slowed the temperature would drop back to the thermostat temperature. Turned out I had a defective thermostat. It was opening but not fully. This was verified by placing it in boiling water. The flow restriction from it not opening fully was the cause of the overheating. A new thermostat put everything back to normal. After checking it in the same pot of boiling water to verify that it opened fully.

 

I've been searching the net for any information on this topic. So far more agree that a thermostat is necessary to slow the coolant, to aid in heat transfer. But they don't give any details as to why. Only one say's that above the need to bring an engine to operating temp, a stat isn't necessary. To me,the profound difference in speed of the coolant, has to tell you, that there is a reason why it's slowed. I'll keep you informed. BTW I work in the real world.

 

Chevynut is right in that an engine with a properly operating cooling system in a cool climate without a thermostat will never warm up. but that same set up in traffic on a hot day will not cool down. The thermostat's function is also to hold the hot coolant in the radiator long enough for the haet exchange to take place. So IMO the thermostat's function is two fold. Just my 2 cents worth.
Rick

 

Hi, You should also notice that there is 3 different type of stat: standard, HI FLOW and safe stat. If a standard stat kept the heat too HI, it is because of the restriction, means you need a HI Flow stat. The safe stat is already with a hole for air pocket and bad circulation caused by rad or water pump. Since the engine run OK without stat but hot with the stat, I suggest to get a HiFlow. My 2c

 

I want to add something that maybe of some help with air pockets. I used to use a procedure to fill the cooling system that has been very effective, but not quite 100% on all vehicles, esp. on fords for some reason, which seem to always have an air pocket waiting to show itself until the coolant gets warm so it gives you a nice warm bath when the air pocket decides to relieve itself from the system. It just takes patience when filling the system. If you pour a/f slowly into the system, it will not trap air pockets as you are filling the radiator. Or, now that I have a vacuum-filling tool, it takes about 15 seconds to fill any system and the system is not only air pocket-free, it holds a vacuum on the system(kind of like a leak check), ensuring a tight leak free cooling system.
The cheaper ones are around 60 bucks, like gates or vacu-fill. Mine has all of the adaptors to fill any radiator or cooling system and ran about 120 bucks. It is a great investment to rule out the chances of having airpockets. Otherwise, take your time when filling the cooling system. Just let it slowly pour in instead of filling it as fast as you can as it pulls/traps air as your filling it. If your impatient, your actually putting the air pockets in the system by filling as fast as you can.
My 2 cents

Jay.

 

SOMETHING I ALWAYS DO WHEN REPLACING THERM. DRILLING 3 OR 4 HOLES
IN THE THERM. NEVER HAD A PROBLEM WITH A AIR POCKET SENSE I STARTED DOING THIS
HOPE THIS HELPS

BUD 1

 

Auggie, glad to see you're thinking about this and are being open minded.

Here's another thing to ponder. No one (at least I don't think they will) will argue that cutting the air flow across the radiator will increase its cooling capacity. It works the same way for the water flow inside the radiator. More water through the tubes is more cooling.

I won't try to add a bunch of technical mumbo jumbo. Just think about that one.

As far as the location of the radiator cap to the hose inlet, I don't know. I never experienced this deal in the "old days", just trying to say that's how the orifices got started in the aftermarket. Think of it this way - there's more pressure in the tank that's connected to the upper hose, and less in the one that's connected to the water pump inlet - since fluids will always flow from high pressure to lower pressure.