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Foam in rad?

Jeepster

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I have just experienced the strangest thing. My BJ8 has been in the garage for the past few months and today the roads are dry (first time in months) so I thought I would sort out the car, ready for a short trip.

I flushed the radiator at the start of the winter and filled with a water and antifreeze mix.

When I returned from my short trip, I noticed what looked like foam dripping under the car. This was coming from the radiator overflow. When I took off the rad cap, foam spurted everywhere and kept flowing from the rad, covering the engine and body panels.
I have now flushed through the rad enough so the foam has all but gone (this took many flushes).

Has anyone else experienced this? where did the foam come from? It was if I had used washing up liquid rather than antifreeze?
 
Oil and water will foam up when heated and agitated. Did the foam have an oily texture? If it did and I don't know Healey engines, but, I would look for an oil leak into the cooling system from, where ever. PJ
 
That's bizarre. If you overfilled the rad you'd get some coolant out of the overflow pipe until the level settled, but it wouldn't be foamy.

My only guess is that something else got into the cooling system, or possibly the AF was contaminated (what brand was it?). Also, if you're using tap water--distilled or deionized is better--there may be something in the water. Did you accidentally use windshield washer fluid instead of antifreeze by any chance? I did that once (but just a little before I realized my screw-up).
 
Auto parts stores sell test strips to detect oil in coolant. I used one once when I was thinking of buying a used car at a "good deal". Not!
 
Hi Jeepster,

You may have a few things going on. One is that you may have induced an air lock, or bubble in the engine the last time you flushed/filled the radiator. When that heats up, it expands faster than the liquid, and can overpressurize the system, causing the overflow and spewing when you open the cap. Second, the foam could be oil/water mix, or may be old, ancient chemicals still in the engine, radiator, heater core that has just broken loose and gone into the liquid stream. I had that happen to me when I first filled my system with new, distilled water and antifreeze. I had flushed the engine, and it was a newly recored radiator, and new heater core along with all new hoses, etc. But I still got a foamy, rusty colored junk that came up into the filler neck. It finally went away as I scooped it off every time I ran the engine.

I would do a pressure check on the system to see if you have any leaks, like a cylinder head or that one spot in the block where it could leak into the cooling. If that proves okay, then run the engine and look for bubbles coming out of the radiator filler, consistantly. If it continues to bubble, at a constant rate, then you probably have a cylinder gasket leak. Also check the spark plugs for moisture, if that occurs...that will confirm the gasket issue. A compression test of the cylinders may also confirm the gasket leak.

Let us know how you fare?

Jerry Rude
BJ8 41423
Lotus Europa TCS
 
Jeepster said:
I have just experienced the strangest thing. My BJ8 has been in the garage for the past few months and today the roads are dry (first time in months) so I thought I would sort out the car, ready for a short trip.

I flushed the radiator at the start of the winter and filled with a water and antifreeze mix.

When I returned from my short trip, I noticed what looked like foam dripping under the car. This was coming from the radiator overflow. When I took off the rad cap, foam spurted everywhere and kept flowing from the rad, covering the engine and body panels.
I have now flushed through the rad enough so the foam has all but gone (this took many flushes).

Has anyone else experienced this? where did the foam come from? It was if I had used washing up liquid rather than antifreeze?
Have you ever added any "stop leaks" to your cooling system such as Barsleak, etc.?
 
HealeyRick said:
You may have a blown head gasket. This will cause oil to mix into the cooling system and the leaking engine compression will cause the mixture to foam up into a nice approximation of a coffee milkshake.

Yep, that would be my guess. Hopefully the head is OK, but if and when you pull it, I'd have it tested too. "Barsleak" (or equivalent) is a temporary solution.
 
If the problem continues, it could be due to a leak between the bottom of the water jacket on the on the left side of the block and the oil galley that is located just below and parallel to it. I have seem this problem many times over the years. The water jacket can rust and corrode over time - maybe a previous owner was not very good at keeping anti-freeze in the engine. 50+ psi oil pressure can force oil through even a pin hole leak into the water. The fix is quite simple, but only after the engine is out and completely stripped down and hot tanked. A ceramic product poured into that water jacket to seal the bottom of the jacket is an easy fix.
I doubt that it's a head gasket, but I have been wrong before. Just ask my ex-wifes.
 
Boink said:
HealeyRick said:
You may have a blown head gasket. This will cause oil to mix into the cooling system and the leaking engine compression will cause the mixture to foam up into a nice approximation of a coffee milkshake.

Yep, that would be my guess. Hopefully the head is OK, but if and when you pull it, I'd have it tested too. "Barsleak" (or equivalent) is a temporary solution.
Clarification: What I meant is that Barsleak can have the same foaming action if there's a leak in the system such as water getting into contact with oil(oil entering into the water cooling system). I've personally seen this.
BTW: I had a V12 Jaguar XJS and it was recommended that two satchels of Barsleak be added after a complete cooling system flush.
 
Patrick67BJ8 said:
Boink said:
HealeyRick said:
You may have a blown head gasket. This will cause oil to mix into the cooling system and the leaking engine compression will cause the mixture to foam up into a nice approximation of a coffee milkshake.

Yep, that would be my guess. Hopefully the head is OK, but if and when you pull it, I'd have it tested too. "Barsleak" (or equivalent) is a temporary solution.
Clarification: What I meant is that Barsleak can have the same foaming action if there's a leak in the system such as water getting into contact with oil(oil entering into the water cooling system). I've personally seen this.
BTW: I had a V12 Jaguar XJS and it was recommended that two satchels of Barsleak be added after a complete cooling system flush.

Ah! Didn't know that. Thanks.
 
I always thought that Barsleak was some thing you bought just to add to the expense of the new radiator you were going to need anyway. [We got back from a hunting trip by pouring ground cinnamon from the cabin's spice collection into the radiator in the Willys]
 
If it is the water jacket into the oil gallery, I remember a mechanical fix on a website a few years ago. IIRC it required drilling the block and inserting a pipe, pressed in, to secure the leak.

Have you found anything out as yet?

Jerry Rude
BJ8
Lotus Europa TCS 'Guenhwyvar'
 
First, this is not an uncommon condition and usually is found in the summer when the fluid level in the radiator is lowered because of loss over time through the overflow. Aeration of the remaining fluid is increased by the water pump and is eventually pushed out of the overflow.

This has happened to me a number of times, especially during a high speed parkway run when stopping to pay a toll. The cure for this is to make sure your fluid level is where it should be or, as I, the installation of an unpressurized overflow recovery system. Unless you find, as others have mentioned, a blown head gasket or cracked head, I would not worry.

I hope this helped,
Ray (64BJ8P1)
 
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