Motor problems

I've got an old Ford 351W which has caused me many problems. total hours are around 800. I have two current problems that may be connected. Last year the motor stopped running. We pulled a head saw water in the cylinders, replaced the head gasket and after some tweaking the boat ran great. Later in the summer I began fouling plugs. the motor has a relatively fresh Holly 650 boat specific carb and a mechanic thinks the rear barrels are dumping gas into the motor. It does often run rich at low speeds. I changed the plugs multiple times which only temporarily solved the problem before they fouled again.

Now for problem #2, When stored at the end of the season I learned there was water in the oil. Could the head gasket installation be faulty? could the block be cracked? instead of pumping in antifreeze we drained the block. Could the water detected be residual water from the earlier gasket problem? What should I do? Pull the carb,and make sure it's right with a clean needle and seat then just run it and change the oil a few times to see if the water works itself out. If it doesn't, I could pull the head(s) and replace the gaskets again and then hope it goes away. Otherwise it's probably the block.

Complicated, I know. Any insights are welcome. Thanks

When stored at the end of the season I learned there was water in the oil.

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Ayuh,.... Welcome Aboard,.... How much water was in the oil,..??

My guess is the floats in the carb need to be reset,....

bondo said:

Ayuh,.... Welcome Aboard,.... How much water was in the oil,..??

My guess is the floats in the carb need to be reset,....

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OK, We'll look into the floats. The bigger problem is the oil in water. Do you think water from the initial head gasket problem could still be in the motor showing up as milk when the oil was drained? Can I just add fresh oil and go ahead and use it after we address the carburetor issue?

Thanks

The bigger problem is the oil in water.

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Ayuh,..... Oil in the water, or water in the oil,..??

Oil in the water, check the oil cooler if so equipped,.....

Water in the oil,....
Drain the water, isolate the blocks coolin' jacket, 'n pressurize with air to 'bout 15 psi, 'n Listen,....
You'll hear the leak, follow the sound to the problem,....

bondo said:

Ayuh,..... Oil in the water, or water in the oil,..??

Oil in the water, check the oil cooler if so equipped,.....

Water in the oil,....
Drain the water, isolate the blocks coolin' jacket, 'n pressurize with air to 'bout 15 psi, 'n Listen,....
You'll hear the leak, follow the sound to the problem,....

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Great Idea. Will do. Fingers crossed!

The next time that you encounter or suspect a potential issue like this, DO NOT remove the cylinder heads until after you have performed a cylinder-leak-down-test.
Once pulled, you've missed this valuable opportunity.


Also, have you considered that the exhaust manifolds or elbows may have been the source of the water?


And.... in the future when you lay-up a Marine Engine, and after draining the exhaust system......, remove the seawater pump impeller, and do a quick 10 to 15 second "dry-start".
This will blow the exhaust dry.

RicardoMarine said:

The next time that you encounter or suspect a potential issue like this, DO NOT remove the cylinder heads until after you have performed a cylinder-leak-down-test.
Once pulled, you've missed this valuable opportunity.


Also, have you considered that the exhaust manifolds or elbows may have been the source of the water?


And.... in the future when you lay-up a Marine Engine, and after draining the exhaust system......, remove the seawater pump impeller, and do a quick 10 to 15 second "dry-start".
This will blow the exhaust dry.

Click to expand...

Thanks Ricardo. I'm looking forward to getting to old girl back in the water in June.Do you have any thoughts on the carb?