The Ford Barn

Sparky · 04-12-2026, 01:23 PM

I took my manifold off today in order to check the valve clearance, and I found a bit of coolant in the rear intake port. I’m guessing I at least need a new head gasket?

nkaminar · 04-12-2026, 02:17 PM

At least a head gasket and that is a good place to start. Is there oil in the coolant or water in the oil? If water in the oil it will look like a chocolate milkshake.

Benson · 04-12-2026, 03:09 PM

Did you remove or loosen the cable clamp from #8 head stud while removing the distributor?

If you did not drain coolant first it can leak past an open valve and into intake manifold.

Sparky · 04-12-2026, 03:14 PM

Quote:

Originally Posted by nkaminar

At least a head gasket and that is a good place to start. Is there oil in the coolant or water in the oil? If water in the oil it will look like a chocolate milkshake.

The oil looks good

Sparky · 04-12-2026, 03:15 PM

Quote:

Originally Posted by Benson

Did you remove or loosen the cable clamp from #8 head stud while removing the distributor?

If you did not drain coolant first it can leak past an open valve and into intake manifold.

I didn’t have to remove the distributor

Sparky · 04-12-2026, 03:21 PM

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I should add that the engine hasn’t been run since last October so apparently it's a slow leak.

johnneilson · 04-12-2026, 04:50 PM

Do you know the history of this engine?
What are the chances it has seats installed for the valves?

Could it be a head gasket, sure, but it could be a lot of other things.

If you haven't removed the head yet, I would pressurize the water system lightly and check in the port. (20-30 psi max)

Have had port rust thru just below the valve seat area, valve seat crack below the seat, crack thru seat into cylinder, you get the point.

Best of luck, John

Joe K · 04-12-2026, 05:38 PM

Possibly the intake port to cylinder wall crack.

Or is that the exhaust port to cylinder wall? And you happen to have caught it before the water got away elsewhere.

The Model B engine was prone to this. My Gordon Smith engine has this crack in cylinder No. 2, but the way the GS head is configured, the "packing" used to reduce the head clearance on the compressor possibly has sealed the leak. At least I've never found any water in the ports or in the oil.

The engine block may have been "chosen" because of this very defect.

While you're apart you can very well check for cracks. EVERYTHING you might need to find/cure a crack at https://goodson.com/collections/crack-detection-repair.

Or before you tear it down you can try one of the "leak check" devices they sell for about $28 at Auto-Zone.

My son has a Toyota Tacoma with 240K miles and an intermittent engine trouble light diagnosis fail on cylinder 1 and 2.

https://www.autozone.com/p/oemtools-...eId=5423627811

Joe K

Synchro909 · 04-12-2026, 07:58 PM

These motors are notorious for cracking from the exhaust valve seat in either #2 or #3 cylinders across to the cylinder and then, if you leave it long enough, down the cylinder wall till the engine doesn't run any more. About 3 years ago I was 2,500 miles from home when the engine blew the manifold right at the back of the block. When I took the manifold off, I found droplet of coolant in the front port. I was in a tiny town with no parts shop (no shops at all) so I rang a couple of friends who were coming along behind us and asked them to bring some Chemiweld. I doubt you guys have that brand but I'm equally sure you will have something similar by another name. I added it to the cooling system hoping it would get me home. Now, 3 years and many thousands of miles later, that engine is still going just fine in another car.The product cures when it reaches fresh air and seals a leak well. My Father in Law used to tell me of the time he used in it his truck as a last resort. It was still there when he sold the ruck 25 years later.
I found this description on he net.
Goss Chem-i-Weld is a chemical compound designed to permanently seal cracks, flaws, and porosity in automotive cooling systems, including cylinder heads, engine blocks, and gaskets. It works on iron, aluminum, steel, brass, and bronze, hardening upon exposure to air in confined spaces. It is generally suitable for repairing small leaks rather than severe over-heating.

Bob Bidonde · 04-13-2026, 08:27 AM

Do this mod.

04-12-2026, 03:21 PM	#6
Sparky Senior Member Join Date: May 2010 Location: Rhode Island Posts: 661	Re: Uh oh, found coolant in the rear intake Sponsored Links (Register now to hide all advertisements) I should add that the engine hasn’t been run since last October so apparently it's a slow leak.

04-12-2026, 04:50 PM	#7
johnneilson Senior Member Join Date: Jun 2010 Location: 34.22 N 118.36 W Posts: 1,205	Re: Uh oh, found coolant in the rear intake Do you know the history of this engine? What are the chances it has seats installed for the valves? Could it be a head gasket, sure, but it could be a lot of other things. If you haven't removed the head yet, I would pressurize the water system lightly and check in the port. (20-30 psi max) Have had port rust thru just below the valve seat area, valve seat crack below the seat, crack thru seat into cylinder, you get the point. Best of luck, John __________________ As Carroll Smith wrote; All Failures are Human in Origin.

04-12-2026, 07:58 PM	#9
Synchro909 Senior Member Join Date: Jun 2014 Location: Melbourne, Australia Posts: 8,434	Re: Uh oh, found coolant in the rear intake These motors are notorious for cracking from the exhaust valve seat in either #2 or #3 cylinders across to the cylinder and then, if you leave it long enough, down the cylinder wall till the engine doesn't run any more. About 3 years ago I was 2,500 miles from home when the engine blew the manifold right at the back of the block. When I took the manifold off, I found droplet of coolant in the front port. I was in a tiny town with no parts shop (no shops at all) so I rang a couple of friends who were coming along behind us and asked them to bring some Chemiweld. I doubt you guys have that brand but I'm equally sure you will have something similar by another name. I added it to the cooling system hoping it would get me home. Now, 3 years and many thousands of miles later, that engine is still going just fine in another car.The product cures when it reaches fresh air and seals a leak well. My Father in Law used to tell me of the time he used in it his truck as a last resort. It was still there when he sold the ruck 25 years later. I found this description on he net. Goss Chem-i-Weld is a chemical compound designed to permanently seal cracks, flaws, and porosity in automotive cooling systems, including cylinder heads, engine blocks, and gaskets. It works on iron, aluminum, steel, brass, and bronze, hardening upon exposure to air in confined spaces. It is generally suitable for repairing small leaks rather than severe over-heating. __________________ When all is said and done, more is said than done. That's why we judge people on what they do, not what they say. I sometimes wonder what happened to the people who asked me for directions. If I am not in trouble, I've done something wrong. Last edited by Synchro909; 04-13-2026 at 05:59 PM.

04-12-2026, 02:17 PM	#2
nkaminar Senior Member Join Date: Jan 2012 Location: Western North Carolina Posts: 6,855	Re: Uh oh, found coolant in the rear intake At least a head gasket and that is a good place to start. Is there oil in the coolant or water in the oil? If water in the oil it will look like a chocolate milkshake. __________________ A is for apple, green as the sky. Step on the gas, for tomorrow I die. Forget the brakes, they really don't work. The clutch always sticks, and starts with a jerk. My car grows red hair, and flies through the air. Driving's a blast, a blast from the past.

04-12-2026, 03:09 PM	#3
Benson Senior Member Join Date: May 2010 Location: Central Highlands, Cen~Col Posts: 2,894	Re: Uh oh, found coolant in the rear intake Did you remove or loosen the cable clamp from #8 head stud while removing the distributor? If you did not drain coolant first it can leak past an open valve and into intake manifold.

04-12-2026, 05:38 PM	#8
Joe K Senior Member Join Date: Jul 2010 Location: Cow Hampshire Posts: 5,015	Re: Uh oh, found coolant in the rear intake Possibly the intake port to cylinder wall crack. Or is that the exhaust port to cylinder wall? And you happen to have caught it before the water got away elsewhere. The Model B engine was prone to this. My Gordon Smith engine has this crack in cylinder No. 2, but the way the GS head is configured, the "packing" used to reduce the head clearance on the compressor possibly has sealed the leak. At least I've never found any water in the ports or in the oil. The engine block may have been "chosen" because of this very defect. While you're apart you can very well check for cracks. EVERYTHING you might need to find/cure a crack at https://goodson.com/collections/crack-detection-repair. Or before you tear it down you can try one of the "leak check" devices they sell for about $28 at Auto-Zone. My son has a Toyota Tacoma with 240K miles and an intermittent engine trouble light diagnosis fail on cylinder 1 and 2. https://www.autozone.com/p/oemtools-...eId=5423627811 Joe K __________________ Shudda kept the horse. Last edited by Joe K; 04-12-2026 at 05:46 PM.