'93 OMC 5.0L Ford Water in Cylinders and Oil

[Jono69]

I am having a kinds of luck this year. Jeez Louise.
After my last weekend trip to the mighty Mississippi, I noticed I had a bit of a milkshake coming out of the crankcase vent tube. Not a lot, but there nonetheless. Got her home no problem. Pulled the dipstick and it is quite overfull with a lovely looking milkshake. Pulled the exhaust manifolds to begin my compression test. Pulled all of the spark plugs and turned it over a few times. Blew a bunch of water out of the port side cylinders, mainly the aft two #7 and #8. The SB side was completely dry. Compression test showed 110-120psi across the board with the exception of #6 (port side) which was at 75psi. I still need to put together a block pressure test rig to check for cracks. I have a hard time believing that I have cracks as the boat was stored and drained properly for a number of years prior to this season and I have ran the crap out of it so far this year with no issues (well besides a couple other non-related things ).
I referenced the Mercruiser service bulletin No. 2001-13 which deals with water intrusion. It said I could have developed a problem such as this due to a overloaded, stern-heavy boat which might have happened over my last trip getting people and gear to the island and back. Also the boat was beached for most of the weekend. We were in and out a lot. This could have caused the water problem, but doesn't address my lower compression in the one cylinder.
Anyone dealt with such an issue or have any ideas??
Thanks guys.
Jon

 

[Redrig]

Re: '93 OMC 5.0L Ford Water in Cylinders and Oil

how does that port manifold and riser look ? any rust trails going into the head?

 

[HT32BSX115]

Re: '93 OMC 5.0L Ford Water in Cylinders and Oil

Hi Jon,


Well you might have more than a couple of things going on. Generally, if you have water only in a "few" cyls, it points to a manifold, riser, or manifold/riser gasket failure that allows some water to run back into an open exhaust valve(s).

That doesn't usually result in much getting directly into the oil. (I ran my previous engine like that for a couple of months)

Another way is an intake gasket leak that allows the front part of the intake gasket to allow water into the "valley" (and into the oil) but that usually doesn't allow much into the cyls.

You could have a cracked head/block blown head gasket etc.

Compression checks will not reveal cracked blocks but might indicate a cracked head and/or blown head gasket.

I think you're on the right track. It's possible that your exhaust "shutters" (OMC calls them an exhaust "seal") might be faulty or have failed and are at the bottom of your Y-pipe.

Your low cyl might just be unrelated to the water (unless you've had water sitting in there for the winter layup) ......and in anycase, all those compression readings are low across the board.


If you have enough water to milk-up the oil, I would pressure check the engine before pulling heads etc.


Regards,


Rick

 

[Jono69]

Re: '93 OMC 5.0L Ford Water in Cylinders and Oil

Hey guys, thanks for the quick responses! The manifold and riser did seems rather rusty in my opinion. Definitely shook some flakes out of them both. As of where I am right now in the process, the only thing I see is the possibility of a manifold/riser issue and or there joining gasket failure. What would be the criteria of either (mani/riser) going "bad"? Could that rust be getting back into the system through a water leak and start screwing with everything else, valves etc? The gasket did look a little fubarred to me.
Anyone have a picture or diagram showing one of their homemade block pressure test setups? I have an idea, but I am more of a visual kind of guy.
I won't be able to get into this one today as I have to go to the in-laws and work on my other boat with a blown-up Merc 170. FML

 

[Idlespeedonly]

Re: '93 OMC 5.0L Ford Water in Cylinders and Oil

You will want a rig that looks like this, or functions like this for testing the engine for leaks.
http://i251.photobucket.com/albums/gg284/randy0048/2011-08-15_16-04-29_14-1.jpg

 

[Jono69]

Re: '93 OMC 5.0L Ford Water in Cylinders and Oil

Thank you Idlespeed, exactly what I was looking for. About what I pictured in my mind.

 

[Idlespeedonly]

Re: '93 OMC 5.0L Ford Water in Cylinders and Oil

15 pound max is all you need also.

 

[HT32BSX115]

Re: '93 OMC 5.0L Ford Water in Cylinders and Oil

Thank you Idlespeed, exactly what I was looking for. About what I pictured in my mind.

Yeah. All you're doing is isolating the block from the exhaust manifolds and risers (because you cannot block them off), closing off all the water input/output connections and then connecting a valve, gage and air compressor.

Put the valve between the block and compressor so you can close the valve after you stop the compressor (so you can hear!) and listen to see if it will hold air.....you'll hear the leak(s) if there are any!

The gage can go anyplace in this plumbers nightmare! (except the compressor "side" of the valve!! )

 

[Jono69]

Re: '93 OMC 5.0L Ford Water in Cylinders and Oil

I assembled a block pressure gauge today and put her on there. It would hold around 15psi but I have air coming through my #6 spark plug hole (all the spark plugs are pulled right now). I am assuming the worst here. That was the cylinder with the low compression (70psi). I do not have time to pull the head tonight as it is a pretty time consuming and labor intensive process on this motor. Hopefully I can get into it tomorrow.
What do you guys think?

 

[Idlespeedonly]

Re: '93 OMC 5.0L Ford Water in Cylinders and Oil

I think bad head gasket.

 

[Jono69]

Re: '93 OMC 5.0L Ford Water in Cylinders and Oil

I think bad head gasket.

I pray that it all it is. I can't afford it to be anything worse!

 

[Jono69]

Re: '93 OMC 5.0L Ford Water in Cylinders and Oil

Well guys... She is cracked. There is a hairline crack between the water jacket and the top of the #2 cylinder. It continues to the head bolt receiver hole. I can't believe it. It must have happened prior to me buying the boat this spring. I know the guy well that sold it and I know he wouldn't have screwed me over on purpose.
The boat is a 1993 Sunbird Regency 195 5.0L HO cobra drive. It is a sharp boat with a lot of nice options. Current NADA value with trailer is about $7000. What do you guys think I should do? Should I try to sell it as is or part out all of the OMC engine and drive and sell the boat and trailer motor/drive-less? I can not unfortunately fork over the cash for a new block at this time due to my current job situation. I am fully capable of the swap, just the funds issue is holding me back. This really Sucks!!
Thank you all so very much for your helpful advice. Much appreciated as always.

 

[HT32BSX115]

Re: '93 OMC 5.0L Ford Water in Cylinders and Oil

That is a REAL bummer! But here's the problem. You have a boat with NO engine. Also, you have a boat with a drive from a company that no longer exists. It also has an engine that is no longer used in marine service. Is it EFI also?

You might be able to get a 5.0L wrecking yard engine and make it work, OR make a few minor changes (different flywheel housing etc) and put a wrecking yard 350 GM block in it. That won't be really cheap either because you will need new manifolds, risers and other marine "stuff" unique to the GM block.

I know the guy well that sold it and I know he wouldn't have screwed me over on purpose.

It might be worth your while to have a talk with him. If he's really a "stand-up" guy, he might step up to the plate and help you out since it's pretty clear he sold you a broken engine. (they don't usually crack after winter)

Sorry about that,


Rick

 

[Jono69]

Re: '93 OMC 5.0L Ford Water in Cylinders and Oil

Thanks Rick. I plan on talking to him about it and see if he knew anything about it. I got a good deal on it from him because of an ugly divorce situation he was going through. Right now my plan is to finish rebuilding my Merc 170 I/O in my Wellcraft and get that thing sold as soon as possible and maybe I will use the money to pickup a new block for this one. Or Just sell both of them and start over!! I think I should be able to get around $3-3500 for the Regency with everything included. We will see. Lot's of different scenarios here but I need to move quick as the boating season is in full swing right now!!