dsm1794

I having a coolant problem, I have coolant ventilation system bypass to where fluid only goes to overflow bottle if the coolant system gets a problem. The last 3 days the coolant has been going to the bottle and now when you open the system it foams everywhere and the foam is a blueish grey and I checked the oil there is not any coolant in there so I need to know what is causing the foam?

Please all ideas would be helpful

Digi7ech

iTrader: (1)

So you have a new radiator cap?

If the system is still pushing after a new cap, then it's over heating and just building way too much pressure or the engine is going.

Check the simple things.
-Bleed all air bubbles
-Check water pump belt
-Check fan clutch
-Replace thermostat

You shouldn't be any where near overheating with the temps we have right now.

dsm1794

I'm not overheating but the pressure popped the top off my overflow bottle twice now and all I'm getting is that foam and not the coolant, and I have 2 new rad caps

Go48

iTrader: (7)

Read this thread. May give you some ideas.
https://www.rx7club.com/showthread.p...ight=champagne

Here's a start: Remove the filler cap on the radiator, not the overflow bottle, start the engine and let it warm up to the point where the top hose feels hot. That indicates the thermostat has opened up. You will see coolant rushing past the open radiator filler neck. That is normal. Don't worry about the minor turbulence or possibly some "gurgling". At that point you are looking for actual obvious bubbling, maybe even foaming, coming up into the filler neck. If that happens, there is almost certainly a failed coolant seal requiring disassembly of the engine to repair.

When doing this, wrap some rags or paper towels around the filler neck to catch the overflow that will happen normally during this process.

lonewolfrx

Is there any smoke coming out? You can try this as well. Try starting the car cold with the radiator cap open and see if starts bubbling up when you start. If it starts bubbling up i believe it may be a coolant seal leak somewhere. Someone correct me if im wrong on this.

SirCygnus

iTrader: (1)

wait... so you are not runing the stock setup? there is supposed to be a nipple under the radiator cap, a hose from this nipple to the overflow bottle and the bottle should be vented to atmos.

you have it vent only if there is problems? wait what?