3.0 Mercruiser Water damage, Seized.

Hi folks,
Question from Australia here I figured you guys have a lot more of these boats engines and may be able to help me, Thanks in advance kinda loooong story.
Boat imported by my Boss Bayliner 175 2005?
Engine 3.0 mercruiser says Nov 2005 on the top of air cleaner.

He used this boat once in salt water and flushed with muffs after use.
Used once in fresh water with "he says no problems".
Parked the boat in his front yard for 12 months untouched:facepalm:.
He Went to use it over xmas you guessed it no go!, He Asked me to come and have a look at his boat as warning buzzer sounded as soon as key moved to "on" position, I thought it had a flat battery. With a fully charged battery would not turn over so I pulled the plugs and it's full of water. Question where has most likely the water come from?
I pulled the head and manifolds, Couple of combustion chambers and valves are rusted, along with surface rust the entire top end, Top of pistons are ok?, Bores have water marks from top down to where pistons are sitting but no scores etc., Have not tried to turn bottom end manually until I work out how bad, The oil is not milky. My guess is the manifolds but they do not look overly bad just suface rust, Question to all you guy's is what's the most common problem with these engines? And what are your thoughts?. I have a local head machining and boring/honing guy who is great to deal with, but before i go down this track I need to source the problem. Or I may get fired

Re: 3.0 Mercruiser Water damage, Seized.

Maybe someone else can backme up but,
I have heard that if the exhaust bellows (on outdrive) are missing/loose/holes, that especially in rough weather or if backing up (also dependent on level of motor/elbows with repsect to waterline) that this can let water straight into the motor. As the head is off, may as well service the whole dammned thing and replace the bellow(s) whilst you are at it as well as checking the SW impellor [what kind of out drive??Mercruiser Alpha I Gen II maybe??].Heck if u get it right is that a pay rise....

Re: 3.0 Mercruiser Water damage, Seized.

Most likely source of the water is a corroded exhaust elbow. They have a life of around 5-7 years and that fits with the age of your engine. Also, they corrode quicker with LESS use, strange as it sounds.

As I say, it not USING a boat that kills it, it's NOT using a boat that kills it.....

Chris...........

Re: 3.0 Mercruiser Water damage, Seized.

Sandbank said:

Maybe someone else can backme up but,
I have heard that if the exhaust bellows (on outdrive) are missing/loose/holes, that especially in rough weather or if backing up (also dependent on level of motor/elbows with repsect to waterline) that this can let water straight into the motor. As the head is off, may as well service the whole dammned thing and replace the bellow(s) whilst you are at it as well as checking the SW impellor [what kind of out drive??Mercruiser Alpha I Gen II maybe??].Heck if u get it right is that a pay rise....

Click to expand...

Not the exhaust bellows, the exhaust shutters (in the exhaust pipe just below the elbow). And since he flushed after use that would rule them out. As it's a 2005 4 cylinder it will be an Alpha One Gen II.... Good idea to check the water pump impeller too, but you'll probably find it's ok.. You MUST use the alignment pins when you put the water pump housing back on. Those long vane pumps are fantastic. I had one on my previous engine that I replaced at 7 years old and it still looked like new.

Re: 3.0 Mercruiser Water damage, Seized.

Most likely source of the water is a corroded exhaust elbow.

Click to expand...

Ayuh,... Or rain water down the carb,.... It sat in the yard for a year....

Re: 3.0 Mercruiser Water damage, Seized.

Have the machine shop pressure test the head and manifold.once you have the cylinder head re-installed,do a cylinder leak down test and you'll know if the block's any good.good luck,ted

Re: 3.0 Mercruiser Water damage, Seized.

Bond-o said:

Ayuh,... Or rain water down the carb,.... It sat in the yard for a year....

Click to expand...

Touch?...

Re: 3.0 Mercruiser Water damage, Seized.

Bond-o said:

Ayuh,... Or rain water down the carb,.... It sat in the yard for a year....

Click to expand...

If water gets on top of the 3.0 manifold it won't all run off so look for evidence of water sitting in the manifold pockets (and flame arrestor), high water mark, evaporation rings, rust.

Once you remove the riser from the manifold, post up pictures of the mating surfaces and gasket. I'd put a bit of ATF (or 50-50 ATF and acetone) on top of the pistons and wipe it on the cylinder walls. If the pistons are stuck, letting the ATF soak in for a couple days will help break them loose.

Re: 3.0 Mercruiser Water damage, Seized.

Thanks for all the reply's more than helpful, I am having the Manifold and head pressure tested. Im new to outdrives and the whole exhaust set up, Could anyone post picture or diagram of the exact parts I'm looking for e.g.. elbows, bellows etc.
Im 99% sure i've got the elbow here on the bench but just want to make sure.
The rainwater is a possibility as there just seems to be minor surface rust everywhere, Although the hatch was shut and it had a cover on it? As for the bottom end should I use ATF to try free it up or is there something better? You guy's are awesome.

Re: 3.0 Mercruiser Water damage, Seized.

Also what is the easiest way to turn engine over manually, Not much room in there!!
Do I have to pull the leg?

Re: 3.0 Mercruiser Water damage, Seized.

3.0's are a PITA to turn over since they don't have a crank bolt. If the engine is free you can tighten the alternator belt really tight, then put a wrench on the alternator nut to turn over the engine. Though, I'm not sure you are going to be able to do that with the rust... When my engine was new and really tight, I put 3 grade 8 bolts (with a big stack of washers underneath each bolt) in the vibration dampner, then turned it over by wedging a big wrench or pry bar in between 2 of the bolts. Be aware, if the engine is really stuck, you could snap off the bolts in the dampner as they are pretty small bolts, 5/16 if I remember correctly.

(Oh yeah, on the washer stack, I put a bigger washer on top of the stack, so the wrench/bar wouldn't slip off the end of the stack.)

Re: 3.0 Mercruiser Water damage, Seized.

CarabbeanSafari said:

...Do I have to pull the leg?

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No... But if it's not been run for a year I would, just to check the impeller... (only takes 10 minutes)

Re: 3.0 Mercruiser Water damage, Seized.

what part of this fine land are you from?

I recently over hauled a 3l due to water ingress. theirs was rain water because they left the hood open.
Almost all 3L's of that vintage in australia need the elbow / manifold replaced . if yours looks anything like this replcase it.



as soon as they become porous they will allow water to run back into the engine.

you may as well give the engine a bit of a birthday, drain the gear oil. remove the bottom box. do the water pump. check for wear in the housing and base plate. If your finger nail catches on the grooves replace them.
Then remove the top box check the uni joint and gimbal bearing (use the grease nipple on the stb side of the transom assy to grease the bearing) as well the bellows rubber. their is a special tool which holds the shift shaft in place when reinstalling the top box. ive never done one with out the tool so you could be in for an experience.

one last thing, on the left and right hand sides of the stern drive you will see 2 discs with 2 wires going to them. stb is trim sender and prt is trim limiter. remove and grease the screws holding these in place.

Re: 3.0 Mercruiser Water damage, Seized.

Peter16 said:

...one last thing, on the left and right hand sides of the stern drive you will see 2 discs with 2 wires going to them. stb is trim sender and prt is trim limiter. remove and grease the screws holding these in place.

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I use a product called 'Aqua-lube', greeny-blue colour and stick as gorilla poo....I also do the bolts holding the upper and lower together, the screws in the top cover of the upper housing and the small bolts holding all the anodes on, especially the ones on the end of the trim rams.... I also used it on the transom through bolts when I installed the engine, and I took the starter motor bolts out and did those....

Re: 3.0 Mercruiser Water damage, Seized.

Peter16 said:

what part of this fine land are you from?

I recently over hauled a 3l due to water ingress. theirs was rain water because they left the hood open.
Almost all 3L's of that vintage in australia need the elbow / manifold replaced . if yours looks anything like this replcase it.



as soon as they become porous they will allow water to run back into the engine.

you may as well give the engine a bit of a birthday, drain the gear oil. remove the bottom box. do the water pump. check for wear in the housing and base plate. If your finger nail catches on the grooves replace them.
Then remove the top box check the uni joint and gimbal bearing (use the grease nipple on the stb side of the transom assy to grease the bearing) as well the bellows rubber. their is a special tool which holds the shift shaft in place when reinstalling the top box. ive never done one with out the tool so you could be in for an experience.

one last thing, on the left and right hand sides of the stern drive you will see 2 discs with 2 wires going to them. stb is trim sender and prt is trim limiter. remove and grease the screws holding these in place.

Click to expand...

Hey mate I'm from Gippsland, Victoria where it's the middle of summer and Today its 17deg strong south wind, Rain, Hail, And snowing down to 1200m WTF? Anyway thanks for all the replays again, Elbow is getting changed if the manifold itself tests ok I'm a safe to put it back on? It really does look to be in good nick. I will tackle the leg as best I can may need some help along the way but I think I can manage it, Is there a good manual for the whole outfit? Cheers

Re: 3.0 Mercruiser Water damage, Seized.

Engine manual -> http://www.4shared.com/document/xEKlzP-s/Service_Manual_26.html
Drive manual -> http://www.4shared.com/document/dPQUcyn_/Service_Manual_14.html
TKS (Carb) Manual -> http://www.4shared.com/document/SNqPsoNI/Service_Manual_41.html

Re: 3.0 Mercruiser Water damage, Seized.

I recently overhauled a 3.0l that had been sitting outside for half a year with the carb off of it. Before i bought it i pulled the dipstick and the oil looked fine. It was only because it had been sitting still and not mixing with about half a gallon of water that the oil was floating on. You may have more water in the oil and if it was sitting on top of the pistons i would guess some must half leaked past the rings in the ring gaps. In my case it was a blessing saved the cam and crank from any corrosion because they were covered in oil that was up in the engine due to the water in the oil pan.

My wife is from Berwick Vic

Re: 3.0 Mercruiser Water damage, Seized.

achris said:

Engine manual -> http://www.4shared.com/document/xEKlzP-s/Service_Manual_26.html
Drive manual -> http://www.4shared.com/document/dPQUcyn_/Service_Manual_14.html
TKS (Carb) Manual -> http://www.4shared.com/document/SNqPsoNI/Service_Manual_41.html

Click to expand...

Awesome thankyou

Re: 3.0 Mercruiser Water damage, Seized.

I hate to tell you, but if an engine has been sitting for a year full of water, you've got to pull the whole engine and disassemble enough of it to inspect the bottom end--oil pan, crank shaft and bearings.

There's no use doing any job half way.

You'd be surprised how easy it is to drop a 4 cylinder Mercruiser engine. You pull the outdrive, unhook the carb & gear cables and battery cables, unplug the wiring harness, unhook the exhaust. Then, it's removing screws holding down the front motor mount and two bolts on each side of the back of the engine. It's maybe a 30 minute job.

Then, find a good automotive machine shop to guide you on what needs to be done.