Foaming from the mouth !!

JOHN CT

Senior Member
I've owned bouncing Betty (my model a) for 20 years now I pretty much understand her personal problems like timing, water levels and all of the other fun things! But today took bouncing Betty out for our first long drive of the season and everything was going great plenty of power no smoke no bangs till I got to a hill and wow foam coming from my radiator cap down the hood and all over the windshield. I noticed the temperature gauge was running hot but I don't know what the temperature was cuz I'm using a quail with the temp. gauge built into in. It's fine on level ground. Got here home after our trip. Opened up the rad. cap set the motor to about 2500 rpm and I'm getting a lot air bubbles mixed in with my 50/50 mix of water & antifreeze. Should I be seeing any bubbles? So my question is what can it be ? I'm afraid it might be a headgasket. What do the experts think? Or what shall I do? So far I know I need new gaskets for my radiator cap to seal it better.
 
Did it steam or put out more vapor at the tail pipe than usual?

Check the oil. If it is creamy colored and foamy there may be water in the oil.

If NO to the above, you may be able to re-torque the head and be OK..follow the procedure in Les Andrew's book.

If it still bubbles through the radiator then your head gasket is probably shot..

There will be more responses!!
 
I have the exact same symptoms in my Roadster. I've ordered a head gasket. I'm going to change the oil and the coolant and I'm going to clean all of the cooling passages in the head before I put it back on.


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Same problem here. Radiator in good shape according to old time shop. Bought a leak down test kit from flea bay. Before I pull the head going to test for combustion leak. Hope the tester don't turn wee wee color:eek:

Sewall
 
Hi John,

FWIW:

This may or may not be your particular problem, however:

I experienced many times years ago where cheap, (non-name-brand), Model A head gaskets, (like in late 1950's and later), were manufactured with thin corrosive steel linings around the interior combustion chamber edges in lieu of copper linings.

This steel lining would rust out and rupture all around the combustion chamber, and would leak in about anywhere from a (2) to (5) year period.

One never knows what kind of Model A head gasket one has; or how it was installed last; unless one installed it by himself.

I would never hesitate to replace an unknown possibly leaking Model A head gasket ........ just remember, anything is possible with an 85+ year vehicle .................. especially a Model A that could have been easily formerly owned by the poorest of the poor before Model A Restoration became popular.
 
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Before doing or accepting any speculation of your Model A's problem, do a compression check.

It is important to find, understand and fix the cause of the problem instead of just arbitrarily changing stuff.

Foaming of the coolant or bubbles in it are not absolute signs of over heating or a blown head gasket. Foaming could be due to a cavitating water pump that aerates the coolant into a froth of foamy bubbles. Also some anti-freezes and additives are prone to foaming. Change the coolant to water only and see what happens.

Another easy test is to feel the radiator after a run. The top half of the core should be hotter than the bottom half. There should no cool places in the core.
 
Before doing or accepting any speculation of your Model A's problem, do a compression check.

It is important to find, understand and fix the cause of the problem instead of just arbitrarily changing stuff.

Foaming of the coolant or bubbles in it are not absolute signs of over heating or a blown head gasket. Foaming could be due to a cavitating water pump that aerates the coolant into a froth of foamy bubbles. Also some anti-freezes and additives are prone to foaming. Change the coolant to water only and see what happens.

Another easy test is to feel the radiator after a run. The top half of the core should be hotter than the bottom half. There should no cool places in the core.
Thanks for the reply. I agree with you I don't want to be a parts changer I would like to diagnose the problem first. I did a compression test a few months ago and I have 65 psi in all 4 cylinders. I think I will take your advice drain the antifreeze and fill with distilled water and take her for a drive, but it still doesn't answer one of my questions about the sudden spike in the water temperature going up hill.
 
A leak down test is preferred over a compression test to diagnose things of this nature.

I usually do a HC sniff test or use a combustion gas tester first, then do a leak down..

If a motor is not missing / running rough a compression test will USUALLY come out normal even with a head gasket causing combustion gasses to enter the cooling system.
 
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The compression test from a few months ago won't tell you anything today. Do another.
Water/foam should NOT come out around the rad cap and onto the w/shield. Repl the gasket(s) under the quail.
How much liquid did you lose?? " Opened up the rad. cap set the motor to about 2500 rpm and I'm getting a lot air bubbles mixed in with my 50/50 mix of water & antifreeze. Should I be seeing any bubbles?" NO

Paul in CT
Most likely the head gasket. JMO
 
A leak down test is preferred over a compression test to diagnose things of this nature.
I usually do a HC sniff test or use a combustion gas tester first, then do a leak down

I've never done a leak down test. Can it be explained her on the ford barn on how it's done? Or is there any one in southern Connecticut that can assets me. I don't want be a parts changer.
 
Yesterday must have been an unlucky test drive day as I also took my Tudoor out for its first spring jaunt & upon return found a white foamy mess in the breather tube w/ a drop in radiator level . Didn't notice any performance drop & temp stayed @ 160 during the drive . Will do a comp test to start with .
I know from past experience getting antifreeze in the oil removes the lubricity so this is a must fix .:(
 
Hi John,

Just a few "bubble" opinions from past Model A cooling experiences.

If your head gasket is not leaking compressed air into your coolant and causing bubbles and foaming ....................... very good chance your semi-clogged radiator is in most cases the problem ....... but "nobody" like this scenario so they install thermostats, change coolant to Sierra, plus try a laundry list of Obama-Care type solutions for overheating.

First, having foaming coolant with bubbles means coolant is full of air ....... and "air bubbles" will "never" cool your engine, with or without anti-freeze.

With lots of Model A radiator "air bubbles", guess what? You got it !!!!!!!! You have instant Model A overheating.

Like explaining how to obtain lung cancer, rather than how to prevent lung cancer, how to make Model A coolant "air-bubbles" in a Model A cooling system may better explain "air bubbles" than how to prevent Model A "air bubbles".

1. One way is if coolant is low, and one goes uphill at about 45 mph, coolant seeks its own level and the high point near the radiator cap has "no" or very little liquid coolant ........ water pump cavitation begins, just like a boat propeller without a cavitation plate making: ................. bubble, bubble, bubbles.

2. Another bubble making way, on level ground, is to rev up the Model A engine and the Model A water pump rotates faster; however, if the radiator is semi-clogged, the faster turning pump cannot get enough water, so it begins the cavitation scenario, again, like a boat propeller begins making bubbles .......... bubble, bubble, bubbles.

3. Many in the past with bubbles in a semi-clogged radiator cut off part of the water pump impeller fins to impede coolant flow ................. others install a thermostat, (some with drilled holes, some without drilled holes), to slow the water flow so the semi-clogged radiator, (depending solely on "gravity" flow through semi-clogged tubes) can keep up with a "now" slower flowing water pump.

5. When Model A's rolled off of the assembly line with full flowing radiators, there were "no" bubbles ................ wow, not many think of that ....... and today, many guys with clean radiators have no bubbles.

6. Later, when Model A radiators became semi-clogged, "nobody" wanted to hear the truth.

Appears it is just like if one has a constipated horse ..... give him a laxative ...... don't cut his ration of oats in half ....... he will never function as well.

Hope this helps future horse owners ...... appears Model A guys today just don't like to clean radiators or even change head gaskets.
 
Hi John,

Just a few "bubble" opinions from past Model A cooling experiences.

If your head gasket is not leaking compressed air into your coolant and causing bubbles and foaming ....................... very good chance your semi-clogged radiator is in most cases the problem ....... but "nobody" like this scenario so they install thermostats, change coolant to Sierra, plus try a laundry list of Obama-Care type solutions for overheating.

First, having foaming coolant with bubbles means coolant is full of air ....... and "air bubbles" will "never" cool your engine, with or without anti-freeze.

With lots of Model A radiator "air bubbles", guess what? You got it !!!!!!!! You have instant Model A overheating.

Like explaining how to obtain lung cancer, rather than how to prevent lung cancer, how to make Model A coolant "air-bubbles" in a Model A cooling system may better explain "air bubbles" than how to prevent Model A "air bubbles".

1. One way is if coolant is low, and one goes uphill at about 45 mph, coolant seeks its own level and the high point near the radiator cap has "no" or very little liquid coolant ........ water pump cavitation begins, just like a boat propeller without a cavitation plate making: ................. bubble, bubble, bubbles.

2. Another bubble making way, on level ground, is to rev up the Model A engine and the Model A water pump rotates faster; however, if the radiator is semi-clogged, the faster turning pump cannot get enough water, so it begins the cavitation scenario, again, like a boat propeller begins making bubbles .......... bubble, bubble, bubbles.

3. Many in the past with bubbles in a semi-clogged radiator cut off part of the water pump impeller fins to impede coolant flow ................. others install a thermostat, (some with drilled holes, some without drilled holes), to slow the water flow so the semi-clogged radiator, (depending solely on "gravity" flow through semi-clogged tubes) can keep up with a "now" slower flowing water pump.

5. When Model A's rolled off of the assembly line with full flowing radiators, there were "no" bubbles ................ wow, not many think of that ....... and today, many guys with clean radiators have no bubbles.

6. Later, when Model A radiators became semi-clogged, "nobody" wanted to hear the truth.

Appears it is just like if one has a constipated horse ..... give him a laxative ...... don't cut his ration of oats in half ....... he will never function as well.

Hope this helps future horse owners ...... appears Model A guys today just don't like to clean radiators or even change head gaskets.

I think you might be right in cavitation with a semi plugged radiator. I had Sierra antifreeze with distilled water 50/50 mix. I drained it out added straight water went for a ride everything seems to be good! Less bubbles and no foam. now the head gasket seems to be fine. Tomorrow I will remove the radiator and give it a good bath. Refill with distilled water and water pump lubricant. I think that's the best and safest way too clean the radiator. Can anyone tell me what is the best way to clean the tubes.
 
Hi John,

In using a Highly Technical Medical Term, for Model A radiators, lots depends on your radiator's constipated conditions :

A. Is it excess water pump grease in tubes ?; or,

B. Is it hard, caked mineral deposits accumulated over many years from creek water, and/or well water, etc., i.e., not using 1930's vintage recommended rain water or distilled water coolant; or,

C. Both.

D. My last "original" semi-clogged radiator was very successfully cleaned of combined grease and mineral deposits with water based POR 15 Marine Clean, which "most" Obama-Care solution guys do not like because of cost ....... I now run my Model A at 50 mph in 100 degree weather with 170 degree coolant after cleaning with Marine Clean; however,

E. Over 50 years ago we used to use "**** & Span", (like, in the "Where were you when the ...... hit the fan"), in original radiators and it also worked well.

F. Modern dish water liquid, like **** & span may work ......... but caution ....... always beware of the "Bubbles" not cooling and take necessary precautions.

Just hoping for the very best of luck for you ....... no doubt you can handle it.
 
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Hi John,

Quick bubbling head gasket leak test without X-Ray, Radar and Cat-Scans is to simply remove spark plugs ..... the clean plug(s) is where the plug(s) and or piston top(s) is getting steamed cleaned with suction of expulsion leaking water .......

Hope this additionally helps simple Model A Radiator Bubble Detection 101 ....... now ........ if your horse is blowing bubbles, that's another subject ..........
 
Regardless if it's a head gasket or not a good radiator is imperative. A restricted radiator will cause an engine a slow death. It will also cause issues such as head gasket problems to arise. purchasing a new radiator is cheaper in the long run., that's usually the route I take
 
Hi John,

Also:

1. Just in case anyone is interested in reading about a very effective, vintage method for cleaning Model T and Model A radiators; &,

2. If one has Victor W. Page's Book, "Model A Ford, Construction, Operation, and Repair"; &,

3. If one can exercise care like thousands of vintage mechanics years ago, one can turn to pages 299, 300, & 301 to read about thoroughly cleaning radiator and engine block rust, scale, carbonate of lime, etc. etc., with a caustic soda solution of 15% to 22%.

4. Solution is made by dissolving and mixing with 2-1/2 pounds of caustic soda per gallon of water to completely fill the entire cooling system ....... this solution was also used to remove old paint and rust from wire wheels as well as other metal items

5. Caution is advised for our much different humans today: ........ today, simple kerosene lamps in a residence are considered by Building Inspectors to be as dangerous as military personnel mines and loaded shotguns ...... times have not changed ...... people have. LOL
 
I had the same problems under heavy load uphills, cooling water not boiling. My radiator is just 2 years old and not blocked. The reason was a cracked head, leaving gases from the combustion chamber to the coolant. If your radiator is ok, Pull the head and before renewing the head gasket, test the head for cracks.
 
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