Serious Water/Oil Problem

[mike7a10]

I am in need of some advice as I have a major water intrusion into the oil problem.

Back in May (you can see my posts from May if you like) I had to rebuild the hot exhaust section. I modified it and ended up with a lot of water in the block. Blew all the water out, reconfigured the exhaust, rebuilt the carb a couple of times and I have had no more problems.

We had not been on boat (which is kept in a slip in saltwater) for about 3 weeks as we were recently out of town. I fired it up on Friday 9/18/09 and it ran great but I noticed the pressure guage seemed very low.

Checked the oil (yes...I should have checked it before I fired it up) and I found very milky oil. I ended up pumping out almost 3 gallons of water/oil. I then changed the oil out 3 times and it was coming up clear even after running in gear tied up at the slip.

Today we went out to put it through her paces and when I got back to the marina after running the engine for about 45 minutes anywhere between 1000and 2200 rpm I ended up pumping out 2 gallons of water/oil mixture. I had noticed that the oil pressure increased from around 30 psi to 40 psi but didn't think much of that as it typically runs around 40 psi at 1800 rpm.

I am suspecting that the exhaust has somehow become clogged and that will be my first check. I will also check the cylinder compression as well.

My biggest question is how can that much water find its way into the sump with only 45 minutes of run time? Could a blown head gasket cause this much water to enter into the sump? The engine is running great...no power loss that I can tell and it is ticking along as usual. I realize it could be the block but in reading the posts Don seems to indicate that is pretty rare and the engine never overheated that I am aware of.

Lastly I guess it could be the water jacket?

This seems to always happen just prior to company coming...

Any advice on how 1.25 gallons of water can enter the sump in 45 minutes or so of run time will be helpful for me to try and figure out where to start.

Thank you in advance.

Mike
S/V Plan Sea

[cloud_nine]

I am fairly new to engine maintenance, but that sounds like a head gasket or less likely a cracked block. I recently seized an A4 from running it with dirty water/oil mixture. It's been an expensive mistake so far.

[Marian Claire]

I seem to remember a post about a hole in the cylinder below the piston stroke. That would allow water in but not effect the compression or performance. I believe a leak in the head gasket would affect performance and the water would have to work by the rings to enter the sump. Dan S/V Marian Claire Found it. Peter,

Congratulations on the great work you've done to this point, and we'll all keep our fingers crossed until you work through this water issue.

The fact that your engine ran so well on your first start-up and 20 minutes into the second run, even as water was obviously entering the crankcase in quite large amounts, is strong evidence that a leak of some kind opened up below the combustion chambers which would eliminate failures of the head, manifold, exhaust system, and a leak in the upper part of the cylinder walls themselves (above the area of piston travel).

Possible causes that meet your symptoms include a "pea-sized" hole opening up in the lower part of one of the cylinder bores, a 1/4" pipe plug leaking in the rear wall of the valve chamber - directly in the middle of the two center valve springs, or a leaky water pump seal if you have an older Sherwood or Jabsco water pump. I consider a leaky water pump seal to be the least likely cause based on the volume of water you seem to be talking about. Leaky water pump seals usually only result in small amounts of water entering the crankcase.

I'm attaching a guide that I hope will help you thorugh a rather simple pressure test of the block and head. The guide is written more from the perspective of a small water leak so you can skip through the part about changing the oil three times etc.

Good luck,

Don

[mike7a10]

Thank you very much for the advice Don. Assuming it is a hole that has opened up in the lower portion of the cylinder...can this be repaired or does this mean the block is shot?

Like most guys who tinker on engines (thank goodness I worked in a filling station as a kid back in the day when mechanics worked at gas stations!) I am more or less a parts changer and can do most routine maintenance such as flushing, changing fluids, tune ups, etc.

If this is the 1/4" plug in the valve chamber, I can probably do this with a buddy of mine who is a darn good car mechanic and who used to work for Caterpillar marine.

I am guessing if this is a hole in the cylinder then we are looking to yank out the engine for a rebuild or looking for a block to rebuild?

Thanks again for your help.

Mike

[joec43]

A blown head gasket will allow an amazing amount of water into the sump.
My head gasket gave up the ghost in Shalomar, FL last year at the fuel dock, and after cleaning plugs, etc, was able to start to run into a slip.

After changing oil, cleaning plugs (I was too dumb to realize the head gasket was gone, thought all the water came from the exhaust), we started and went out to sea.

Only later did I realize the head gasket was blown, and when I removed the plugs from hole 1, the water was gushing the full size of the hole.

So yea, a head gasket leak COULD be the cause, this would show up on a compression test (use Don's test, put your thumb over the hole and crank). You will know very quickly if this is the issue.

Good luck!!

[mike7a10]

Thanks Joe! I will be checking that this morning.

Mike

[Marian Claire]

I feel I have caused some confusion on this thread. After my original post I found the post I was looking for. I edited to include the extra info. I did not make it clear that this was a cut and paste job of a previous post on a different thread by Don. Dan S/V Marian Claire

[Dave Neptune]

Mike, ther are many ways that water can get into the engine and many are listed above. I seriously doubt that the water is coming in from the exhaust side unless it is filling ( via back-syphon ) when the engine is off which doesn't appear to be the case. I suggest a compression check and if it seems OK ie no major changes from the previous compression checks the head-gasket is probably OK. Try removing the intake manifold and preassure check it although if the manifold was leaking you should have major performance issues. The water can get in by being sucked into the intake gasses, however it still needs to get past the rings and you are talking about a lot of water, still doubtfull.
As I recall there are a couple of "pipe plugs" inside the water jacket that may have failed. These could let in the amounts of water that you are describing. Otherwise it's a big leak into the crankcase as it would be difficult to have a motor running with that much water trying to get past the rings and not drowning out or missfiring badly. Hopefully you do not have a crack or hole rusted through the block somewhere as that would be catastrophic. I havce a 39 year old A-4 that is raw salt water cooled and it is still ticking, the Hi-nickle block of the A-4 is very good at resisting rusting through.

Dave Neptune

[mike7a10]

Thanks Dan. I figured out that this had been a cut and paste after I replied back.

Anyway...thanks again for the info.

Mike

[mike7a10]

Thanks Dave. I am checking everything out today. Came back for lunch and I am plugging away at the most obvious stuff and keeping my fingers crossed it isn't a block issue.

Mike

[keelcooler]

Our blocks rarely fail. The alloy used on water jacket plate, head and manifold seem to rot out first.

As said, pull the valve cover and look for rotted out pipe plug right in the middle.You can rig up a bike air pump and start pressure testing systems.

[mike7a10]

The compression test revealed that I have anywhere from 100 to 110 psi in each cylinder so I have eliminated the head gasket.

After having spent most of the day in the tiny engine well I have removed the water lift muffler. It was full of rust and crud but I don't think this is the problem. It looks like a steel water lift (obviously not stainless steel). I have a water lift that I will be installing later this week.

I have also removed the water pump as the weep holes were totally blocked but again I doubt this is the issue although I am going to thoroughly clean the housing.

If the water lift replacement and cleaning the water pump do not do the trick the only other thing I can think to do with the boat in the water is to check the valves to see if the water plug has given out.

If that is OK then the engine has to come out for major inspections. Not sure when I can do this as I anticipate that this will be (at least) an "all day" adventure as I have a center cockpit and you have to maneuver the engine out to the internal walk-through/walkway then get it up and out the companion way into the center cockpit and then arrange to get the engine out of the cockpit and onto a dolly on the dock...not to mention getting into a truck and out into the garage. Shees! I'm worn out just thinking about it. It is still hitting 90 degrees every afternoon with humidity in the 80's/90's! Come on fall!!

OK everyone...thanks again for all of the advice. I will post as "progress" is made.

(Thank you Keelcooler...I'm on it.)

Mike
S/V Plan Sea

[roadnsky]

Originally Posted by mike7a10

If the water lift replacement and cleaning the water pump do not do the trick the only other thing I can think to do with the boat in the water is to check the valves to see if the water plug has given out.

Mike-
Don't forget to check the water jacket before you pull the engine!
Unless you don't have access to that side?

[mike7a10]

Thank you Jerry...unfortunately I cannot really get to the water jacket side plate due to space constrictions. I would need to pull it out to do that and once I pull it out I may as well take it home and clean it up.

Thanks again.

Mike

[mike7a10]

Update: I have replaced the water lift muffler. The good news is the engine has never been so quiet. The bad news is that I changed out the oil and ran it up to about 1400 rpms in gear tied up to the slip. After about 5 minutes of running in gear hot water and oil literally pushed out of the oil filler in the front of the engine.

Immediately shut it down and pumped out gallons of hot saltwater into the bilge and then pumped out the oil separately into a container. Added new oil to the engine, pulled the plugs (they were bone dry) and added MMO to each cylinder and spun the engine after pulling the distributor wire.

The problem of water intrusion into the sump has gone from bad to worse. As always you have to look at the most recent change and that was replacing the water lift muffler. I don't think the muffler or the exhaust is causing the water issue. (I just had a thought that I better recheck the muffler today to make sure I didn't hook it up backwards...that would be one explanation! I am pretty darn sure I installed it correctly.)

I am guessing that something internally (hopefully a plug) has continued to rust out further. It is also possible that there was a reduction in back pressure with the new muffler that allowed water to fill even more quickly.

I will have to now pull the engine for a major inspection. I am keeping my fingers crossed that it is an internal plug and not a hole in the metal jackets or cylinder/s.

Will keep you posted, and again thanks to everyone for their input!

Mike

[keelcooler]

Mike, If the problem was the exhaust, head or manifold water would be getting into the combustion chambers. Don't run the motor until you find and repair the source.
You do not want to damage bearings and alike. If you can pull the carb you should be able to remove the valve cover and check that plug.

[Stinn]

Mike,

for what it's worth... check the anti siphon valve. If it's not at the proper height or plugged you will draw water back into the engine when you turn it off. had this problem on a 79 cat 30.

[tony201]

Do all A 4s have the plugs in the valve chamber ? I don't recall seeing any when I did my overhaul

Tony

[keelcooler]

Tony, I found no plugged casting hole when I did a valve job. I understand that some did.

From what I know, I can only conclude three causes for large volume of raw water making it's way to base pan oil.

Rotted out casting plug in valve spring chamber.
Hole in block, lower areas of cooling jacket, or piston jacket.
Water and oil seal failures water pump shaft ( unlikely,water and oil would be pouring out of weep hole)

A plugged anti siphon would fill up combustion chambers.

It has been said a machine shop can repair a piston jacket hole with a insert sleeve. Are you 100% no waters have been found in combustion chambers?

[mike7a10]

The plugs were absolutely dry and the top of pistons that I could see through the plug holes were dry as well.

As to the anti-siphon, I don't have an anti-siphon as that "T" is used to loop into my hot water heater. Please know that I have never had an anti-siphon in this engine before and never had any problems with water until recently.

I agree that since the cylinders are bone dry I don't suspect that this is a siphon problem. I am pretty sure at this point it is either an internal freeze plug or I have a hole that has rusted through the water jacket or worse, the lower portion of a cylinder. At this point since ALL the cylinders are dry I don't suspect that it is a hole in a cylinder...but I can't rule anything out until I get the engine pulled. I am not sure when this will happen but I hope to have it out and in the garage sometime in the next 2 weeks.

Thanks again to all who have kindly responded. I will re-post when I get the engine out and inspected.

Mike

[Don Moyer]

Tony 201,

If you mean the 1/4" pipe plug in the very center of the back wall of the valve chamber, the answer is no. These plugs were only used when Universal found a small leak in the water jacket in that location; caused by the wire which was suspending the sand core during the initial casting process. I have no idea why only this location seems to have presented that particular problem. I'm not aware of this repair method ever being used anywhere else on the block. Perhaps our engineering colleagues can shed some light on the subject.

Don

[mike7a10]

I have pulled the engine and it is in the garage. I have pulled the valve cover and have examined the valve chamber and cannot see any type of casting plug... I read one of Don's historical posts that said that these casting holes were found typically in engines with serial numbers higher than 194000. My serial number is 194453. Should this casting plug be visible without having to remove the valves? I read that it should be found on the rear wall of the valve chamber.

I also removed the water jacket plate and have been poking around in there. I cannot see any plugs there as well...

Am I not looking at (or for) the right thing?

Thanks in advance.

Mike

[keelcooler]

Pump it up Mike. Put the plate back on for pressure testing. Otherwise strip it down and give to the machine shop to find.

[mike7a10]

I will pump it up! That should at least give me the answer to if the block is cracked.

Thanks Keelcooler.

Mike

[Don Moyer]

Mike,

You're looking in the correct place for the 1/4" pipe plug (in the center of the back wall of the valve chamber), but please remember that only a very few engines ever had this pipe plug installed. We can only recall of approximately 5 in 17 years. The plug was only installed if Universal discovered that a small pin hole leak existed in this part of the casting. That being said, even though it's a long shot, it's still worth while to look for the plug if you're experiencing a water leak somewhere in your water jacket.

Don