Engine is spitting anti freeze through catch tank

[michel schryer]

I have this problem with my anti freeze spitting out my catch cylinder tank.
My engine is a 302 5.0L with gt40 heads and a mild E303 cam. The cap is screwed on a CSR 45 degree aluminium elbow which is mounted on the original housing. I installed a big braided hose from the CSR housing to the top hose of the rad and noticed that the middle part of the hose is slightly above the thermostat filling point where my cap is creating an air pocket. Takes me forever to fill the system. Could that cause the system to overpressurize. I think the rad cap is 10 or 15 psi.
I guess i have too much pressure in the system and at some point it spits out the anti freeze. My catch tank is just a small cylinder that vents to the atmosphere. I changed the rad cap which is not on the rad but on the thermostat housing and it still spits it out. Could i just remove the thermostat and hope it solves the problem or it's the hose that is too high. Those CSR housing are not cheap and don't really want to buy another one, need some advice here, thanks !

Michel

[Z-linkCobra]

What are the temp readings when your having this problem? If its not getting hot then you could have too much water in the system. I know that sounds ass backwards but you need some room for expansion. Empty your catch can and as long as your not getting hot let it level itself out. I have had several cars through the years that would spit coolant down to a certain level and be just fine.

Is this a new build or something you have run for some time? If its a new build and its getting hot your head gaskets may be installed wrong.

[DesertMK4]

I have a 302 as well. It would vent when the engine was shut off. The cure was a larger catch tank. The FFR cylinder tank holds JUST enough but then is empty at start up or vents some excess when shut down hot. I could never get the balance just right. Larger tank no problem since.

Originally Posted by michel schryer

I have this problem with my anti freeze spitting out my catch cylinder tank.
My engine is a 302 5.0L with gt40 heads and a mild E303 cam. The cap is screwed on a CSR 45 degree aluminium elbow which is mounted on the original housing. I installed a big braided hose from the CSR housing to the top hose of the rad and noticed that the middle part of the hose is slightly above the thermostat filling point where my cap is creating an air pocket. Takes me forever to fill the system. Could that cause the system to overpressurize. I think the rad cap is 10 or 15 psi.
I guess i have too much pressure in the system and at some point it spits out the anti freeze. My catch tank is just a small cylinder that vents to the atmosphere. I changed the rad cap which is not on the rad but on the thermostat housing and it still spits it out. Could i just remove the thermostat and hope it solves the problem or it's the hose that is too high. Those CSR housing are not cheap and don't really want to buy another one, need some advice here, thanks !

Michel

[DesertMK4]

I had the same problem for a while with the FFR cylinder catch tank. I put in a larger tank and no problem since. With the smaller tank it would go empty on cool down but would vent a little when shut down hot. I could never balance the two extremes with the smaller FFR tank.

[Gaz64]

Your cooling system pressure is going above the cap rating.

Overheating, poor circulation, poor design (won't bleed properly etc), head gasket leak etc.

Ignition timing also.

[jhv48]

I too had the same problem with my FFR. I Put in a larger overflow bottle and that solved that problem.

Same thing with my SPF. If I filled the expansion tank more than 3/4 full, it would puke some out. Installed a recovery bottle and now the expansion tank stays full, and the excess is forced into the recovery tank. Make sure you get one that holds at least 32 ounces.

If this doesn't help, then we'll have to dig deeper. Start with the simple stuff first.

[CHANMADD]

is that radiator cap a two or a one way .........

[michel schryer]

My catch tank is not very big and I fill the system to the brim, also I fill the catch tank half . I might put too much liquid in like you said, no room for expansion because when i do that I come back from a ride and it spitted it out, I will try with less coolant until it doesn't spit it out and if it doesn't overheat it means i was filling the system too much. My temperature is 190 degree Celcius on the temp gauge stable when hot outside. I have no leaks just a little sippage at the thermostat gasket that i have to replace, it didn't seal right i guess. It's been like that since the beginning and I've replace the stock heads with gt-40's. I think it's a lack of understanding. Thanks for any ideas, I really appreciate

Originally Posted by Z-linkCobra

What are the temp readings when your having this problem? If its not getting hot then you could have too much water in the system. I know that sounds ass backwards but you need some room for expansion. Empty your catch can and as long as your not getting hot let it level itself out. I have had several cars through the years that would spit coolant down to a certain level and be just fine.

Is this a new build or something you have run for some time? If its a new build and its getting hot your head gaskets may be installed wrong.

[michel schryer]

I have no idea if it's one way or two. It has a little flap at the bottom that's all i know. I replaced the one I had with this one that i bought at a hot rod shop. Like some other guys said, i might have filled the system too much and my catch tank is probably too small, will have to replace it with a bigger one until the system equalizes. Thanks !

Originally Posted by CHANMADD

is that radiator cap a two or a one way .........

[Turbonut48]

Your system wont operate correctly until you eliminate the leaks. It wont suck the fluid back when cooling down. It ll suck air.
Make sure you have correct type and pressure cap.

The Nut

[Z-linkCobra]

If your head gaskets were on backwards it would run hot very quickly...so we eliminated that possibility. Try a larger catch can, fix your leaks and let it spit some out until it quits and go from there.

[michel schryer]

I will fix the leak but do I need a thermostat ? I don't have a heater or anything like that and drive only in the summer.

[Z-linkCobra]

You need something to regulate the flow of water. If the water does not stay in the radiator long enough to cool down then you have accomplished nothing. You don't want a cold running motor nor do you want excessive heat. I like somewhere around 170 to 190. New cars run 210 to 220 and that is not hot as long as you have water.

I would put a 180 t-stat in it and call it good.

[michel schryer]

Should i change my rad cap for more psi you think. It makes a lot of sense, didn't think about what a rad is there for. It's funny because my temp gauge is in celcius and they are Autometers and the temperature indicates 190 stable when engine is running in hot summer days. Should it be 190 farenheit. All the gauges I've got are "Autometer" . I didn't think that temp gauge would be in Celcius, though the kit was bought in Canada and it's made by a Canadian guy buy my speedo is in MPH, anybody saw those temp gauges in Celcius before.

Originally Posted by Z-linkCobra

You need something to regulate the flow of water. If the water does not stay in the radiator long enough to cool down then you have accomplished nothing. You don't want a cold running motor nor do you want excessive heat. I like somewhere around 170 to 190. New cars run 210 to 220 and that is not hot as long as you have water.

I would put a 180 t-stat in it and call it good.

[Z-linkCobra]

according to google 190 celcius is 374 f. That's a tad too hot...lol. Im thinking your gauges are f not c. At 374 you would be spewing water everywhere and things would get ugly real quick. I had a 74 bronco with a 302 in it and autometer gauges. I pegged the temp gauge one time in a mud bog at 350 f.....it was not pretty.

I like a 13-16lb cap for a street motor. If your over pressurizing the system and spewing water the cap is likely not your problem. Find out if your gauges are indeed celcius or farenheit.

[michel schryer]

I'm pretty sure my gauge reads Celcius wich is weird, I will check it again but I could be wrong or it was a mislabeled, the car is on the lift covered for the winter but I'll check again. For the thermostat story, I read an article that said that a thermostat is not necessary if you have no use for it. If the water is flowing more it won't stay in the block stagnant and accumulating heat since it's always flowing, that's why they have high flow water pumps.
One guy did a test without and with and he found that with the water flowing constantly the engine never overheated. I will try it and see what happens. Thermostat are good to control the temperature, we'll see. I will also install a bigger expansion tank so if the fluid wants to spit out it will return back to the rad keeping it full, my catch tank is venting to the atmosphere right now, no return, just a waste of fluid, decreased volume in my rad. I'm learning here I think, trial by errors, thanks bud for your inputs !

Originally Posted by Z-linkCobra

according to google 190 celcius is 374 f. That's a tad too hot...lol. Im thinking your gauges are f not c. At 374 you would be spewing water everywhere and things would get ugly real quick. I had a 74 bronco with a 302 in it and autometer gauges. I pegged the temp gauge one time in a mud bog at 350 f.....it was not pretty.

I like a 13-16lb cap for a street motor. If your over pressurizing the system and spewing water the cap is likely not your problem. Find out if your gauges are indeed celcius or farenheit.

[jhv48]

Keep the thermostat, add the coolant recovery tank.

Then test.

[CHANMADD]

Hey........without a thermostat it may appear to run ok................the coolant will eventually be passing through the radiator so fast that when it returns to the engine via the lower radiator hose it will not have spent enough time in the radiator to cool, ...so it will return hot and just get hotter and hotter.....

[michel schryer]

You have a point but with the coolant flowing faster through the engine it doesn't have the time to overheat because it flows constantly and still pass through the rad, that's what I read in an article about that and why do big companies make high flow pumps if it gets trapped in the rad waiting to past the thermostat. Anyway I will keep the thermostat for now and buy a 2qz recovery tank from Breeze automotive or Canton, it should solve my problem , thanks bud !

Originally Posted by CHANMADD

Hey........without a thermostat it may appear to run ok................the coolant will eventually be passing through the radiator so fast that when it returns to the engine via the lower radiator hose it will not have spent enough time in the radiator to cool, ...so it will return hot and just get hotter and hotter.....

[CHANMADD]

Did you read what I wrote.........?