water leaking from plug

[JOHN COOKSON]

In the original post you said that water was leaking from around the #4 spark plug. How did the water get from inside cylinder #4 to outside spark plug #4? Was the spark plug corroded or somehow not seated very well?

I noticed this too. Sort of figured there was two problems - water dripping onto #4 spark plug and water getting into the cylinder by way of the manifold because of poor exhaust system plumbing.
BB2 please clarify for us.

TRUE GRIT

[BLACKBIRD2]

not good,,,

The motor turned over,, ran for a bit a minute, two maybe ,,then died..pulled plugs, #4,and #3 cylinders,,,were wet,#1 seemed fine, water in oil,,not as bad as before,,,left the plugs out, laid a towel over the plug holes, and turned the motor over,, and #4,#3,, a huge wet spot on the towel #1,#2 was dry,,Left, the plugs out, changed the oil, let ever thing dry out, pored a shot of mmo in the cylinders, ,,went back this morning, ,with high hopes,plugs in, fresh oil, ..,,started after a few cranks, AGAIN, ran a minute ,,then died,,pulled the plugs, #3#4 wet again, pulled plugs ,towel over the holes turn over the motor,and again big wet spot, for #3,#4,,,,The Thu hull for the raw water intake was only open for seconds, before the motor stalled,,so is the head gasket ,,and or the head need replacing?..what i do know is the motor ran fine, from st. Augustine, to marathon,,,i did have to do a field repair on the exhaust,,on the way down, then i replaced the manifold, and exhaust,,, now things have headed south,,HEY its a boat, ,,all apart of the joy..

[CalebD]

Replacing the head gaskets is not the most difficult job, IF that is what you need to do. You would need to use 2 gaskets that are sold here; 2 of the same head gasket - as recommended per Don Moyer.

I sometimes get some moisture on the engine head at higher revs for some duration. On my engine it comes from the studs that hold the "lifting eye"/alternator bracket and flows into spark plug depresssions of #3 or #4 - giving the impression that it might be coming from the cylinder.
Replaced the head gaskets some years ago but I may be looking for a new head at some point.

Has your oil cleaned up or is there more "milky" water in it after a short run?

Maybe taking the head off and examining it closely is not such a bad idea. Replace with new gaskets anyway.

[ndutton]

I think a pressure test of the cooling system is in order and if it fails, smaller isolated pressure tests to follow (block, manifold). You may be able to find the area of the problem before taking things apart then take a targeted approach.

I also would not discount the possibility of multiple issues. A one to two minute run time before shut down is coincidentally about the same time it takes to run through a carburetor bowl of fuel without replenishment. We don't like coincidences. One thing at a time though, follow where the testing leads.

[BLACKBIRD2]

the milky oil has cleared up for now [3 changes],,pulled the carb, going to clean ,,check things out,,the anti-siphon loop appears to be okay,,ordered head gaskets today,,i also have another motor that i used for my manifold,,and will use if i need another head,,it will probably come to that im afraid,,

[CalebD]

Milky oil should clean up in about 3 oil changes. Been there, done that.

Your problems might clear up with replacing the head gaskets but bear in mind what Neil Duitton just mentioned:
- pressure testing the cooling circuit, even if you have to blow into it
- the fuel pump could also be the culprit. To test for this you can be brave and remove the fuel line after the pump to check if there is flow from the pump while the engine is running. I don't recommend this practice but it will prove whether or not the fuel pump is working (mechanical or electrical). You may spill some gas in the process.

Neil brings up a good point that there is only a few minutes of running time in the fuel hoses of most engine set ups. Could be there is no fuel delivery.

Do you routinely turn off your gas tanks petcock when the boat is not in use?

And is this a "V" drive installation?

[BLACKBIRD2]

CalebD it is a 2;1 reduction,and i to turn off my fuel ,when not in use,,,im going over this morning ,,reattach the carb, and check the elec. fuel pump out ,,,Thanks again to everyone for all the advice

[BLACKBIRD2]

replaced the fuel pump,[elec.],,hung the carb,started and died,,, the raw water intake was only opened for a few seconds after the motor started, still water in #4,,and a little in #3.,Neil, the pressure testing is next,i will see what i can put together for tools,,for my testing,,,cheers,,hope ever ones weekend was good,

[ndutton]

Home Depot carries this in their plumbing department for cheap.

[BLACKBIRD2]

Well i ran a compression test on my cylinders, not looking good, #4-68..#3-65
#2-90,,#1-0,,what would cause a reading of 0,,if the head gasket was/is bad ,,should it have some,,compression,,,

[Mo]

Compression numbers indicate valves stuck. Don't pull the head just yet although it may have to happen. Initially I'd devise a little tube douse the valves with penetrating oil.

1. Remove all plugs (number your wires with tape so you don't put them back on in the wrong order)
2. Get a small flexible tubing from hardware store...clear is good about 1/4 inch diameter.
3. Pick up a can of PB Blaster.
4. Insert the tube so that it goes over next to the valve. Look in with a light and you will see the valves off to the right about 4 inches on a forward facing engine...if you engine is reversed, opposite side.
5. Spray allot of PB blaster into the tube so that it makes it's way over to the valves...you want to soak them....dont be shy with the spray.
6. An hour later do it again...repeat 3 or 4 times over the next few hours.
7. Turn the engine over on starter...repeat spray if you notice valves have not moved. No need to put plugs back in but take off coil wire and cover to contain spark...beware of fuel and fumes.
8. Might want to try this a couple of days and they might free up.

That number one is likely stuck, the other two may or may not indicate a head gasket leak. With the high probability of number one stuck it's very possible the other low numbers are partially stuck.

There are a few other things you can try like removing the side plate and freeing the valves that way, however, with so many showing poor numbers, I'd remove head after no response from above effort. Once head is removed you free and reseat the valves, new head gasket, good to go....be patient for a couple of days and you might not have to go there.

[Mo]

Worth a try.

Compression numbers indicate valves stuck. Don't pull the head just yet although it may have to happen. Initially I'd devise a little tube douse the valves with penetrating oil.

1. Remove all plugs (number your wires with tape so you don't put them back on in the wrong order)
2. Get a small flexible tubing from hardware store...clear is good about 1/4 inch diameter.
3. Pick up a can of PB Blaster.
4. Insert the tube so that it goes over next to the valve. Look in with a light and you will see the valves off to the right about 4 inches on a forward facing engine...if you engine is reversed, opposite side.
5. Spray allot of PB blaster into the tube so that it makes it's way over to the valves...you want to soak them....dont be shy with the spray.
6. An hour later do it again...repeat 3 or 4 times over the next few hours.
7. Turn the engine over on starter...repeat spray if you notice valves have not moved. No need to put plugs back in but take off coil wire and cover to contain spark...beware of fuel and fumes.
8. Might want to try this a couple of days and they might free up.

That number one is likely stuck, the other two may or may not indicate a head gasket leak. With the high probability of number one stuck it's very possible the other low numbers are stuck in different positions.

There are a few other things you can try like removing the side plate and freeing the valves that way, however, with so many showing poor numbers, I'd remove head after no response from above effort. Once head is removed you free and reseat the valves, new head gasket, good to go....be patient for a couple of days and you might not have to go there.

[edwardc]

A 0 psi reading is usually caused by a stuck valve. It can frequently be freed by the patient application of Marvel Mystery Oil. Squirt some in the cylinder thru the spark plug hole, trying to aim for the valves. Turn the engine over by hand a few times and let it sit for a day. Retest the compression. Repeat as necessary. It may take a week until it comes loose, so be patient.

Edit - Mo types faster!

[BobMcD]

Zero could be caused by a stuck open valve!

[Al Schober]

Agree that the 0 psi reading is a stuck valve. Verify visually through the spark plug hole or by removing the valve cover plate. Suggestions for freeing the valve/lifter are good. Engine should run OK if you get #1 working.
#3 and #4 are quite low - my guess is bad valve seats, probably exhaust. Could also be a bad head gasket between #3 and #4. These low pressures shouldn't keep the engine from running OK.
What's the history on this engine? These engines do have to be overhauled periodically, primarily for rings. Oil consumption, smoke in the cabin?
Occasionally for bearings - hows your oil pressure?